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Mehrotra, Shilpee. "An evaluation of the impact of introducing a breakfast club on nutritional status and cognitive function in lower social class primary school children." Thesis, Queen Margaret University, 2005. https://eresearch.qmu.ac.uk/handle/20.500.12289/7363.
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Breakfast has been shown to increase the supply of glucose to the brain which improves short-term memory. On waking hepatic glycogenolysis is the major buffer against short-term (12-18 hrs) fasting. The higher ratio of brain weight to liver weight in the child (1.4 - 1.6 versus 0.73 for the adult) and the 50% greater metabolic rate per unit brain weight in the child, places a greater demand on the child's glycogenic stores during a short fast as compared to the adult. Few school breakfast studies have examined the effect of different breakfasts on cognitive performance. This study investigated the nutritional differences of a habitual breakfast consumed at hom (NBC) and breakfast served at a breakfast club in (BC) school and the effect of these breakfasts on cognitive performance. Subjects were primary school children aged 7-11 years old in Scotland. When baseline cognitive performance scores were compared to scored at data collections 2,3 and 4 there were more significantly pronounced improvements for the NBC group than the BC group (p < 0.001). There were significantly greater numbers of children eating a cooked breakfast in the BC group and significantly higher numbers of children eating a cereal breakfast in the NBC group. As a result breakfasts of the BC group were higher in fat (MUFA and PUFA) (p < 0.01) and lower in percentage energy from carbohydrate than the NBC group. Positive correlations existed between percentage energy from carbohydrate and percentage energy from starch and cognitive test performance (p < 0.01). This suggests that a breakfast higher in % energy from carbohydrate such as a cereal breakfast benefits short-term memory, by supplying the brain with readily available supply of glucose it's primary and preferred fuel. This results of this research provide evidence for the requirement of guidelines to ensure that breakfasts served at school will both assist learning in morning lessons and be in-line with healthy eating recommendations.
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Zohren, Jasmin. "Introgression in Betula species of different ploidy levels and the analysis of the Betula nana genome." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24564.
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Two of the most rapid drivers of evolution are hybridisation and polyploidisation. Hybridisation allows the rapid introduction of novel genetic material, potentially much faster than mutations, but this process is impeded by reproductive barriers between species. Differencesinploidylevelcanformsuchabarrier. Hybridisationaswellaspolyploidyareknown to occur frequently in the plant kingdom, including the genus Betula, which is investigated in this thesis. Three species of the Betula genus that exist in the United Kingdom are studied here: B. nana (dwarf birch), B. pendula (silver birch), and B. pubescens (downy birch). They differ in ploidy: B. nana and B. pendula are diploid and B. pubescens is a tetraploid. HybridisationandgeneflowbetweenthesethreespecieswasanalysedbyusingaRAD-seq dataset derived from 196 wild individuals. It was found that introgression acts unidirectionally from the diploid into the tetraploid species and that there is a cline of introgression between the north and south of the UK. This result suggests a range shift of the species from different distributions in the past. Gene flow from B. nana to B. pubescens could be a neutral or even maladaptive consequence of their past species distributions. Alternatively, it could be an adaptive process: alleles from B. nana could be helping B. pubescens to adapt to harsher, more northerly populations. To gain a preliminary understanding of the possible effects of introgression, the loci in close linkage to RAD tags introgressed from B. nana into B. pubescens were investigated and their putative function inferred by comparing their homologs in related species. To enhance the analyses, a draft whole genome sequence assembly of a B. nana individual was improved with long read data generated by PacBio sequencing, as well as the addition of RNA-seq data. This produced a more contiguous and complete reference sequence, enabling a closer look at more genes in linkage to the RAD tags.
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Jennings, Arthur John. "Practical work in school secondary science and the curriculum influence of its assessment, with particular reference to biological science." Thesis, University College London (University of London), 1995. http://discovery.ucl.ac.uk/10020245/.
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Practical work in secondary school science has long held a prominent position. With particular reference to biology this thesis, which is essentially a reflective study, examines the way practical science has developed over the last fifty years. Major curriculum revisions are considered in the light of both changing educational insights and societal expectations during this half century which has seen remarkable changes affecting all aspects of life. The primary focus, however, concerns the influence of practical assessment on the teaching of biology. In a chronological sequence the transition of biology is traced from its position as a minority curriculum subject with a predominantly descriptive approach suitable for its morphological and taxonomic emphasis to its place within balanced science for all pupils of compulsory school age. The struggle of biology to emerge as a rigorous school science and the adaptation of biology curricula to accommodate a biosocial synthesis fitting to a society that has become increasingly environmentally aware forms an important strand through the account. Always, though, the effect of examinations and what is examinable has affected teaching priorities and teaching approaches. Therefore this thesis looks at pivotal curriculum and examination changes and seeks to evaluate the match of examinations to curriculum goals. The conclusion is made that practical examinations have frequently served curriculum aims, especially at times of syllabus revision but during periods of relative curriculum and examination stability practical assessment has sometimes exerted a constraining influence. Despite all the changes in science education during the past fifty years practical science has maintained its high profile. Whilst the stated aims of practical work have taken different emphases at different times there is evidence that teachers have persistently lacked clarity about its precise purpose. Despite modem rhetoric about 'doing science' and the national curriculum thrust towards investigations teachers still cling to very general beliefs about the value of practical science even though there is a significant change in disposition towards more investigatory science.
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Lawton, Kirstie. "The impact of a healthy eating intervention : a comparative, longitudinal observation of dietary intake, knowledge and behaviour in council sector nursery school children and their parents in Edinburgh." Thesis, Queen Margaret University, 2016. https://eresearch.qmu.ac.uk/handle/20.500.12289/7376.
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Good nutrition is essential for optimal growth and functional development in children. Research indicates that the preschool years are essential for encouraging children to develop a taste for healthy food. Scotland’s obesity rates are amongst the highest in the world, and in areas of low socio-economic status, obesity and related conditions are considered to be most prevalent. It is also widely reported that areas of deprivation are related to poor dietary intake. In 2004, Edinburgh Community Food Initiative (ECFI) was responsible for initiatives that were based on ECFI’s ‘provide and promote’ philosophy, combining health promotion activities with the provision of fresh fruit and vegetables to schools, child and family centres and community centres in the most disadvantaged communities of Edinburgh. Funding was acquired from the Big Lottery Fund to initiate a citywide health initiative in the nursery school setting called ‘the Pip Project’. The aim of this research was to identify dietary intake at baseline in pre-school children and their parents from council sector nurseries, and to observe changes in dietary intake and behaviour over a period of 20 months, comparing dietary intake of children and their parents from areas of lower socio-economic status who received the Pip project interventions to those from areas of higher socio-economic status, who did not. Dietary intake was recorded using a 5 day diet diary at three time points; prior to nursery school attendance (August 2005), at completion of year one (June 2006), and two months prior to leaving nursery (April 2007). A questionnaire was also completed to determine knowledge and dietary behaviour at baseline (August 2005) and at the end of the research period (April 2007). Baseline intake was compared to the National Diet and Nutrition Surveys for adults and for children aged 1.5 to 4.5 years, the Payne and Belton Edinburgh preschool dietary survey, the Food Standards Agency Low Income Diet and Nutrition Survey, and the standards devised by UK Scientific Advisory Committee for Nutrition (SACN). Results at baseline were comparable to results from other national surveys. Research indicated that all adults were aware of the 5 a day message and 80 % thought that 400 g was ‘just right’ or ‘not enough’. Adults, and particularly those from the lower SES group, had clear knowledge of what constituted one portion of fruit or vegetables and did not report any barriers to healthy eating, however at baseline fruit and vegetable intake was 260 g/d, which was significantly lower (p = < 0.05) than the recommended 400 g/d and intakes were significantly less (p = < 0.05) in the lower SES group (219.5 g/d compared with 297.5 g/d in the higher SES group). Minimal increase was seen in fruit and vegetable intake of adults from the lower SES group, who consumed significantly less (p = < 0.05) than adults from the higher SES group by the end of the 20 month research period; children from the lower SES increased their intake by 1 portion (82 g) per day but still consumed less than the children from the higher SES group by stage 3 (203 g/d compared to 253 g/d). At baseline, the diet was balanced for adults and children in terms of % energy from CHO and fat, but mean intakes of both NME sugar and saturated fat were greater than the recommended maximum intake of 11 % total food energy. Mean intake NME sugar in children was 17.9 %; intakes were greater in the higher SES group (19.5 % compared to 16.6 %). Mean intakes were also significantly greater (p = < 0.05) in the parents from the higher SES group (15.2 % compared to 11 %). Mean intakes of NME sugar in parents decreased in both groups over the 18-month duration of the study but mean intakes in children remained high throughout the research period. Saturated fat intakes increased in adults from both SES groups, but were higher in the lower SES group at all stages. There was no change in mean saturated fat intake over time in children from the higher SES group, but mean intake decreased in children from the lower SES group (from 16.2 % to 14.1 %). Mean intake of NSP increased in both parents and children, but remained below the recommended 18 g/d throughout the study. With the exception of iron, mean intakes of all micronutrients for parents were greater than the RNI in both groups. Iron intake was lower than the RNI (14.8 mg/d) at all stages. At baseline intakes were lowest in the lower SES group (9.3 mg/d compared to 11.4 mg/d); 11 participants consumed less than the LRNI (8 mg/d), eight of whom from the lower SES group (73 % of participants). Mean intakes increased in the lower SES group by 3.7 mg/d over the duration of the study but neither group reached the RNI at any stage. At baseline, children met the RNI for all micronutrients, and there were no significant differences between groups. Overall the diet of children, particularly from the lower SES group, improved over the duration of the study, although salt and NME sugar intake did not decrease over time. Further research is required to investigate the best methods to improve diet in families with young children, with particular emphasis on reducing % energy from NME sugar and saturated fat, reducing salt intake and increasing fruit, vegetable and NSP intake.
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Ståhle, Gunnarsson Katarina. "Skolgården - inflytande och pedagogiska perspektiv The school yard - influence and pedagogical perspectives." Thesis, Malmö högskola, Lärarutbildningen (LUT), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-35761.
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AbstractGunnarsson, Katarina Ståhle (2011). Skolgården – inflytande och pedagogiska perspektiv. Malmö: Lärarutbildningen, Malmö högskola.Syftet med denna studie är att undersöka och jämföra några elevers, lärares och politikers tankar och planer. Är de lika eller skiljer de sig åt vad gäller vistelsen på skolgården? Jag har genom kvalitativa intervjuer av elever, lärare och några av de som planerar skolgården samt observationer samlat in mitt empiriska material, detta har genomförts på en skola i södra Sverige. Min utgångspunkt har varit tidigare forskning och studier kring den fysiska utomhusmiljön på en skola. De teoretiker jag utgått från är Dewey och Vygotskij samt bland annat de Jong och Nordin-Hultman som tidigare forskare.Resultatet visar att eleverna beskriver och resonerar kring sin skolgård och användandet av den på ungefär samma sätt, oberoende av vilken grupp de tillhör eller hur gamla de är. Vad gäller lärarna så skiljer sig deras sätt att se på och använda sig av skolgården som pedagogisk miljö, även om vissa likheter förekommer. Av undersökningen framgår det tydligt att eleverna inte är delaktiga i skolgårdens utformning i någon större utsträckning. De blir tillfrågade endast via elev- och miljöråd om hur de vill att den kommande skolgården ska se ut, men elevernas svar synliggörs inte så i realiteten har eleverna inte något att säga till om vad gäller skolgården.Nyckelord: fysisk utemiljö, inflytande, pedagogisk miljö, skola, skolgård
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Bui, Ann. "Beach burial of cetaceans implications for conservation, and public health and safety : a thesis submitted through the Earth & Ocean Sciences Research Institute, and School of Applied Sciences, Auckland University of Technology in partial fulfillment [sic] of the degree of Master of Applied Science, March 2009." Click here to access this resource online, 2009. http://hdl.handle.net/10292/669.
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Every year hundreds of cetaceans strand on New Zealand beaches. Options for dealing with disposal of their carcasses are few, creating significant problems for the Department of Conservation (DOC). More often than not their carcasses are buried in beaches at or just above high water mark, near where the animals have stranded. The primary objective of this thesis is to determine the effects of cetacean burial on beach sediments, and evaluate potential health and safety risks associated with this practice. A secondary objective of this thesis is to appraise the appropriateness of one location DOC has repeatedly transported cetacean carcasses to and buried within beach sediments, Motutapu Island in Waitemata Harbour. The chemical effects of cetacean burial over a six-month period are reported for two sites at which animals were buried in 2008, Muriwai and Pakiri beaches; the biological effects of this burial are reported for one of these sites, Muriwai Beach, 12 months post burial. Intertidal faunal and floral inventories are provided for six sites around Motutapu Island, and these then compared and contrasted with inventories compiled from an additional 290 intertidal sites between Whangarei Heads and Tauranga Harbour, North Island East Coast, to appraise the relative uniqueness of intertidal species diversity around Motutapu Island. At both Muriwai and Pakiri beaches, nitrogen and phosphate concentrations in surface sands changed considerably following cetacean burial, although over six months the effect was localized and elevated concentrations of these two chemicals that could be attributed to a buried carcass did not extend more than 40 m from the site of whale burial. Deep-core profiles revealed nitrogen and phosphate concentrations at and in the immediate vicinity of cetacean burial approximately six months after burial to be markedly elevated to the level of the water table, but elevated concentrations attributable to the buried carcass were not observed greater than 25 m from the site of burial. Elevated concentrations of nitrogen and phosphates in beaches persist in surface sediments for at least six months post burial. Twelve months post cetacean burial no significant difference in species richness or abundance were apparent in intertidal communities extending along transects proximal to and some distance from the Muriwai Beach carcass; there is no evidence for any significant short-term (to 12 months) biological effects of cetacean burial in beaches. Of those shores on Motutapu Island accessible by earth-moving equipment and large vessels capable of dealing with and transporting large cetacean carcasses, Station Bay appeared to be the most appropriate site for whale burial. However its small size and relatively high biological value (fairly high species richness for comparable shores between Whangarei Heads and Tauranga) renders it an inappropriate long-term option for whale burial. Other shores on Motutapu Island host some of the highest species richness of all shores surveyed between Whangarei Heads and Tauranga Harbour, rendering them entirely inappropriate locations for burying cetaceans, over and above other variables that may influence disposal location identification (such as archaeological sites, dwellings and accessibility). Motutapu Island is not considered an appropriate location for cetacean burial within beaches. Alternative disposal strategies need to be explored for dealing with cetaceans that strand on Auckland east coast beaches. Although burial is the most convenient and most economical strategy to dispose of cetacean carcass, especially in mass stranding events or when cetaceans are of large size, and the biological effects of this practice are not considered significant (for the one whale that could be studied), persistent enrichment of beach sediments with organic matter could result in prolonged persistence of pathogens in beaches, causing unforeseen risks to human health and safety. Recommendations are made to minimize possible threats to public following burial of cetaceans in beaches, until the potential health risks of burial are more fully understood.
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Wedel, Elsa. "Ecosystem Services as a Pedagogical Perspective for Teaching the Importance of Biodiversity to High School Students." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-148588.
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Reducing the rate at which biodiversity is presently being lost is one of the challenges for the coming years. Through diverse activities, humankind is currently responsible for the extinction of species worldwide, which has consequences for whole ecosystems. The preservation of biodiversity is not only important for its intrinsic values, but also for its role in maintaining the functioning of ecosystems that provide humans with services that are important for our well-being and safety. As it is a concern for all of humanity there is a demand for education that can develop in students an understanding of the complexity which lies behind the ecosystem services of which they benefit. Including how the disturbance of this complexity will lead to consequences for the whole human world. Current attempts to educate the public has failed to conjure motivation and interest. However, ecological network research create opportunity for understanding the underlying relationships between species, and the use of ecosystem services as a pedagogical perspective offers the possibility to demonstrate the importance of these relationships for ecosystem functioning. In this literature review it is examined how this could benefit environmental education in high school.
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Kumlin, Terese. "Social science students’ perceptions of motivational methods and approaches in science class." Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-36394.
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How to motivate students effectively is a question teachers have asked for thousands ofyears. In my teaching program at Malmö University, a variety of teaching methods andapproaches, that also increase motivation, have come into focus. These include:teaching at the right level, using a variety of teaching methods, seeing every student,being enthusiastic about the material, using formative evaluation, connecting lessons tostudents’ everyday life, and adapting classes to students’ interests. The aim of this studyis to find out how secondary students in a social science program perceive teachingmethods and approaches aimed at increasing motivation, and determine which methodsthey perceive as most/least effective. The study used both qualitative and quantitativemethods. 23 upper-secondary students from a class at a school in southern Swedenwere interviewed in four focus groups, where participants were purposefully sampled.10 of these students were also asked to complete a questionnaire ranking the teachingmethods and approaches on a scale of 1-7 (where 1 was most effective at increasingmotivation and 7 least effective), and the mean values of these scores were used in theanalysis. A phenomenological approach and content analysis were used to code andanalyze the data. Students perceived all of the motivational methods to be effective, themost effective being teaching lessons at the right level, followed by using a variety ofteaching methods, with mean values of 1.9 and 3.2, respectively. Adapting lessons tostudents’ interests and connecting them to everyday life were the least effective, withmean values of 5.6 and 5.7, respectively. The categories of teachers having a positiveattitude towards the material and the students, and seeing every student, had the samemean value, 3.8, while formative evaluation had a mean value of 3.9. When trying tomotivate students, it would thus appear more effective to make sure that lessons aretaught at the right level and that teachers vary the lessons, than to adapt lessons tostudents’ interests or connect the material to everyday life. While this was a small studyand the findings cannot be generalized to school populations, they are of high interestfor the researcher.
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Higgins, Ruben, and Adegran Olof Thalberg. "Miljöundervisningen i F-3 – svårt men fullt möjligt. Environmental education in primary school – difficult but fully possible." Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-31536.
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Syftet med detta examensarbete är att undersöka yrkesverksamma lärares upplevelser av möjligheter och utmaningar i sin miljö- och hållbarhetsundervisning. Detta då vi genom egna erfarenheter genom reaktioner från vänner och bekanta eller i samtal med lärare under vår vfu uppfattat No-ämnen, där även miljö- och hållbarhetsundervisningen ingår, som för komplext och abstrakt för att kunna läras ut i åldrarna F-3. I vårt arbete har vi studerat lärare i årkurs F-3 för att undersöka vilka utmaningar och möjligheter som upplevdes i miljö- och hållbarhetsundervisning. Vi har även analyserat traditioner i miljöundervisningen för att diskutera hur komplexiteten i hållbarhetsfrågor kommer fram. För att kunna genomföra vår undersökning använde vi oss av semistrukturerade intervjuer som efter transkribering användes i en innehållsanalys. I resultatet fann vi att lärarnas förmåga att använda närmiljön fungerade som en möjlighet att praktiskt förankra undervisningen samt lägga den på en passande nivå för eleverna. Under utmaningar var det bristen på tid som tydligast framkom.Normerande miljöundervisning med inslag av en faktabaserad tradition, är det perspektiv som dominerar i lärarnas berättelser. Den mer komplexa pluralistiska traditionen var däremot inte så tydlig.The purpose of this study is to investigate the teachers' perceptions of opportunities and challenges in the environmental and sustainability education. This because through our own experiences and reactions from friends, acquaintances but also conversations with teachers during our internship, we have perceived the subject of science to be conceived as too complex and abstract to be taught in primary school. In our study, we have interviewed teachers in grades K-3 to examine the challenges and opportunities experienced in environmental and sustainability education. We have also analyzed the traditions of environmental education to discuss how the complexity of sustainability issues is portrayed. To carry out our study we used semi-structured interviews and after transcribing them they were used in a content analysis. In the result, we found that teachers' ability to use the local environment served as an opportunity to anchor the practical teaching and put it on a suitable level for the students. The lack of time was the most prominent challenge reported by the teachers. Normative environmental education with elements of a factual tradition, is the perspective that dominates the teachers' stories. The more complex pluralistic tradition, however, was not so clear.
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Cheema, Tabinda Shahid, of Western Sydney Nepean University, and Faculty of Education. "Laboratory based instruction in Pakistan: comparative evaluation of three laboratory instruction methods in biological science at higher secondary school level." THESIS_FE_XXX_Cheema_T.xml, 1994. http://handle.uws.edu.au:8081/1959.7/271.
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This study of laboratory based instruction at higher secondary school level was an attempt to gain some insight into the effectiveness of three laboratory instruction methods: cooperative group instruction method, individualised instruction method and lecture demonstration method on biology achievement and retention. A Randomised subjects, Pre-test Post-test Comparative Methods Design was applied. Three groups of students from a year 11 class in Pakistan conducted experiments using the different laboratory instruction methods. Pre-tests, achievement tests after the experiments and retention tests one month later were administered. Results showed no significant difference between the groups on total achievement and retention, nor was there any significant difference on knowledge and comprehension test scores or skills performance. Future research investigating a similar problem is suggestedMaster of Education (Hons)
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Jansson, Gunilla, and Marie Ekholm. "En jämförande studie av förskollärares syn på naturvetenskap och teknik i förskolan/ A comparative study of preschool teachers’ views of science and technology in pre-school." Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-29133.
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Bakgrunden till vår studie är att naturvetenskap och teknik fått större plats i förskolans läroplan samtidigt som studier visat på att det finns brister i arbetet med dessa ämnen på skolor och förskolor. Syftet med studien var att få syn på likheter och skillnader i hur fyra förskollärare, från en ämnesinriktad och en traditionell förskola, ser på naturvetenskap och teknik samt arbetssätt och ämneskunskapens betydelse. Vi har gjort en kvalitativ studie och som metod valde vi att göra enskilda intervjuer som spelades in med ljudupptagning. De teoretiska utgångspunkter som använts i analysen har fokus på det sociokulturella perspektivet. Resultatet visar att de likheter som finns är att förskollärarna anser att grunden för barns lärande är ett utforskande och undersökande arbetsätt i samspel med barn och vuxna. Det som skiljer sig är i hur man ser på och vad naturvetenskap och teknik innebär samt vad ämneskunskapen har för betydelse. Slutsatsen är att det inte spelar någon större roll vilken förskola man arbetar på utan det är intresset hos förskolläraren som styr arbetet med naturvetenskap och teknik.
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Stanley, Cory McKelvey. "An experimental approach to teaching the concept of functional diversity." [Johnson City, Tenn. : East Tennessee State University], 2002. http://etd-submit.etsu.edu/etd/theses/available/etd-0306102-164828/unrestricted/stanleyc041402.pdf.
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Norris, Carina. "Nutrient content of different types of lunchtime meal, and their contribution towards the overall daily nutrient intakes of 11-14-year-old schoolchildren from two schools in Scotland." Thesis, Queen Margaret University, 2010. https://eresearch.qmu.ac.uk/handle/20.500.12289/7378.
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Introduction Due to concern regarding the quality and health implications of schoolchildren’s diets, large amounts of funding have been invested into improving school canteen lunches. However, children may also have packed lunches, or ‘street’ lunches (those purchased outside school). This study was undertaken to ascertain whether canteen lunches are nutritionally superior to packed and street lunches, the contribution of the lunch types towards total nutritional intake, and whether children who eat nutritionally poor lunches compensate with food consumed at other times. Method During 2007 and 2008, dietary intake data was collected from 332 children aged 11 - 14, from two secondary schools in Fife, Scotland. Using 5-day estimated intake food diaries, data from 1,532 days was collected. Nutrient intake and density for 9 nutrients (plus fruit/vegetables) included in the Scottish Nutrient Standards for School Meals (2003) were compared with the Scottish Nutrient Standards for School Lunches (for lunchtimes) and Dietary Reference Values (for the whole day). Comparisons were undertaken between canteen, packed and street lunches, and between days including them. Results Many children ‘flitted’ between canteen, packed and street lunches on different days. Some children also consumed food from more than one lunch type on a single day. Dietary quality was poor; intakes of non starch polysaccharide, iron, and fruit and vegetables (at lunchtime and over the whole day) were of particular concern. When canteen lunches were consumed, the diet was closest to guidelines. However, many dietary targets remained unmet. When street lunches were consumed, the diet was furthest from the guidelines. This was the case both at lunchtime and over the whole day. There was some compensation for poor lunchtime nutrient intake by foods eaten at other times during the day. However, this was not as great as noted by previous studies, and many significant differences between the lunch types existed at the end of the day. Conclusion Due to the superior nutritional quality of canteen lunches compared with the other options available, and the contribution of canteen lunches towards overall nutrient intake, children should be encouraged to have canteen lunches.
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Behrendt, Marc E. "It is an Experience, Not a Lesson: The Nature of High School Students' Experiences at a Biological Field Station." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1388769652.
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Stewart, Matthew Blair. "Computational and experimental investigations of biologically interesting molecules." full-text, 2009. http://eprints.vu.edu.au/1957/1/MBStewart_PhD_Thesis.pdf.
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The reconciliation of experimental and computational data is an on-going challenge in many fields of scientific enquiry. This is particularly true in chemistry, especially with respect to biologically interesting molecules, given the myriad of problems that now lend themselves to theoretical investigation. This work sampled several areas of this greater landscape using various computational methods, and compared these results to relevant, experimentally derived data.
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Gustafsson, Mikael, and Rikard Ask. "Betydelsen av utomhuspedagogik för elevers lärande inom naturvetenskap." Thesis, Malmö universitet, Fakulteten för lärande och samhälle (LS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-28798.
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AbstractOutdoor education is a concept of the idea where you teach matters. This study asks the question of what significance outdoor education has for learning in natural science and how motivation influence the learning of the students.For young students in natural science it is important that they have the possibility to vary their environmental setting to be able to get firsthand and authentic experiences of life, nature, society and culture in its natural place, so that they can use that in their early education. A variety of how the students learn should mix between literal- and sense-based learning. Several of the studies that we have researched shows the same thing, outdoor education has an impact on the knowledge and skillset within natural science for the students. Yet it is rarely used to the extent that maybe it should within education. It does however not stop there; outside education also motivates students to learn both in the outside and inside settings.
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Moreira, Edjane Farias. "Competências dos licenciados em biologia para o ensino de ciências no nono ano do ensino fundamental." Universidade Federal de Sergipe, 2015. https://ri.ufs.br/handle/riufs/5208.
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This research has the subject matter of analyzing the competence of licensed teachers in biological sciences to teach a science course in the ninth grade of middle school, considering that this course covers introductory concepts of physics and chemistry. Faced with the need to understand the competence of biology teachers to teach that discipline and the replacement of licensed teachers in Biological Sciences by licensed teachers in Chemistry and Physics in private schools, we propose the following specific objectives: outline aspects of the competence of licensed teachers in Biological Sciences for the teaching of the science course in the ninth grade of middle school, and analyze the strategies used by such teachers in teaching science course in the ninth grade of middle school. In order to have those objectives achieved, an descriptive approach was adopted, outlining the main characteristics of the sample investigated, formed by 39 professionals licensed in Biological Sciences, who teach the Science discipline in the ninth grade of middle schools in public and private schools in Sergipe. In addition, qualitative and quantitative analysis of data collected through the questionnaire consisted of 23 questions applied to the sample was adopted. As a result, it was observed that most of the 39 professionals licensed in Biological Sciences do not feel prepared to teach science discipline, blaming the Degree course in Biological Sciences by not complementing more appropriately related curriculum materials or corresponding teaching practices. However, we understand that, because of their professional experience with middle school students, the Biological Sciences Professor would rather be competent to teach this discipline, since it can mobilize resources more easily to teach the science discipline in the middle school, according to what is on the curriculum of the courses of Biological Sciences graduation.Esta pesquisa tem como objeto o estudo a analisar a competência dos professores licenciados em Ciências Biológicas para lecionar a disciplina Ciências no nono ano do ensino fundamental, considerando que essa disciplina aborda as noções introdutórias de Física e Química. Diante da necessidade de compreender a competência dos professores de Biologia para lecionar tal disciplina e da substituição dos licenciados em Ciências Biológicas por professores licenciados em Química e Física em escolas particulares propomos os seguintes objetivos específicos: delinear aspectos da competência dos professores licenciados em Ciências Biológicas para o ensino da disciplina Ciências no nono ano do ensino fundamental; e, analisar as estratégias utilizadas por tais professores no ensino da disciplina Ciências no nono ano do ensino fundamental. Para que tais objetivos fossem atingidos, adotou-se uma abordagem descritiva, delineando-se as características principais da amostra investigada, formada por 39 profissionais licenciados em Ciências Biológicas, que lecionam a disciplina Ciências no nono ano do ensino fundamental de escolas públicas e particulares sergipanas. Além disso, adotou-se abordagem qualitativa e quantitativa dos dados levantados através do questionário formado por 23 questões aplicado à amostra. Como resultado, observou-se que a maior parte dos 39 profissionais licenciados em Ciências Biológicas que não se sente preparadas para ensinar a disciplina Ciências, responsabilizando o curso Licenciatura de Ciências Biológicas por não complementar mais adequadamente conteúdos curriculares relacionadas ou práticas de ensino correspondentes. Contudo, entendemos que, em razão de experiência desses docentes com alunos do ensino fundamental, o profissional licenciado em Ciências Biológicas seria competente para lecionar tal disciplina, uma vez que o mesmo pode mobilizar recursos didáticos mais adequadamente para o ensino da disciplina Ciências no ensino fundamental, dado o que consta nos currículos dos cursos de Licenciatura em Ciências Biológicas.
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Thörne, Karin. "Teaching genetics - a linguistic challenge : A classroom study of secondary teachers' talk about genes, traits and proteins." Licentiate thesis, Karlstads universitet, Avdelningen för biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-15311.
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The overall aim of this thesis is to investigate how teachers talk about genetics in actual classroom situations. An understanding of how language is used in action can give detailed information about how the subject matter is presented to the students as well as insights in linguistic challenges. From the viewpoint of seeing language to be at the very core of teaching and learning, this study investigates teachers’ spoken language in the classroom in topics within genetics that are known to be both crucial and problematic. Four lower secondary school teachers in compulsory school grade 9 (15-16 years old) were observed and recorded through a whole sequence of genetic teaching. The empirical data consisted of 45 recorded lessons. The teachers’ verbal communication was analyzed using thematic pattern analysis, which is based on the framework of systemic functional linguistics (SFL). The focus of the thesis is to determine how teachers talk about the relationships between the concepts of gene, protein and trait, i.e. the functional aspects of genetics. Prior research suggests that this is a central aspect of genetics education, but at the same time it is problematic for students to understand because the concepts belong to different organizational levels. In the first study I investigated how the concepts of gene and trait were related in the context of Mendelian genetics. My results revealed that the teachers’ way of talking resulted in different meanings regarding the relationship between gene and trait: 1) the gene as an active entity causing the trait 2) the gene as a passive entity identified by the trait 3) the gene as having the trait, and 4) the gene as being the trait. Moreover it was found that the old term anlag was regularly used by the teachers as synonym for both gene and trait. In the second study I examined how teachers included proteins in their lessons, and if and how they discussed proteins as a link between different organizational levels. This study showed that teachers commonly did not emphasize the many functions of proteins in our body. The main message of all teachers was that proteins are built. Two of the teachers used proteins as a link between gene and trait, whereas two of them did not. None of the teachers talked explicitly about genes as exclusively coding for proteins, which implies that the gene codes for both proteins and traits. The linguistic analysis of teachers’ talk in action revealed that small nuances in language used by the teachers resulted in different meanings of the spoken language. Thus, my work identifies several linguistic challenges in the teaching of genetics.This thesis is written within the framework of the Hasselblad Foundation Graduate School, a four-year programme financed by the Hasselblad Foundation.
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McIntosh, Cecilia A., Karin Bartoszuk, and Scott Kirkby. "Professional Development Provided by the School of Graduate Studies: Enhancing Mentoring and the Graduate Student Experience." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/363.
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East Tennessee State University has taken several approaches to offering professional development for graduate students over the past several years. This includes graduate student research grants, thesis and dissertation awards, teaching awards, awards for service for the public good, Graduate Student Success Specialist service, Thesis/Dissertation/Capstone Boot Camp, Add-on Fellowships, GA Fee Scholarship, Thesis/Dissertation Scholarships, formal courses (GRAD), graduate student research magazine, and workshops. These will be briefly described, including funding sources supporting the initiatives. A mention of professional development for faculty will also be presented. There will be ample time for discussion of strategies and sharing of ideas by participants.
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Devaiah, Shivakumar P., and Cecelia A. McIntosh. "Towards Understanding of Glucosyltransferase Specifi city in Citrus Paradisi." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/350.
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Flavonoids are a broad class of low molecular weight, secondary plant phenolics characterized by the fl avan nucleus. Widely distributed in plants, food and traditional herbal medicines, more than 6000 fl avonoids have been identifi ed up to date. They are present mainly as glycosides whose phenolic hydrogen or hydrogens are substituted to sugar moiety. An increasing number of fl avonoids have attracted much attention in relation to their biological activities, including anti-viral, anti-infl ammatory, anti-bacterial, and vasodilatory activities. Present work is to understand the structure and function of a fl avonol specifi c glucosyltransferase from Citrus paradisi. The study is one of the many steps towards custom designing of the protein. We employed homology modeling, site-directed mutagenesis and yeast expression system to generate mutants of glucosyltransferase and study their substrate specifi city, regiospecifi city and kinetic properties.
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McIntosh, Cecilia A. "Building and Sustaining Research at East Tennessee State University." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/366.
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Bidwell, Joseph, Cerrone Foster, Anna Hiatt, Cecelia A. McIntosh, and Rebecca Pyles. "Progress on Implementing Transformative Approaches in Southern Appalachia." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/354.
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Over the last year the Faculty of Biological Sciences at East Tennessee State University have been evaluating core coursework for biology majors and working towards transforming teaching approaches to enhance the undergraduate learning experience and improve overall learning outcomes among our graduates. Our institution serves a large population of low-income and first generation college students living and working in Southern Appalachian region. The most important motivation behind transformation is to provide highly-qualified graduates who can contribute to the economic development and growth of the area. In focusing on traineeship and skills development of graduates, we adopted an action plan focused on students, faculty, and curriculum development. Under the leadership of the chair, productive and positive discourse on curricular goals among faculty has shaped well-defined core concepts and competencies we envision for our graduates. Several faculty are using research-based methods to improve the core curriculum and to infuse best teaching practices in the classroom. The strengths of our program lie in having demonstrated success in providing students with authentic research experiences in upper-level courses. We are working towards infusing these ideas and skills-development into the introductory core curriculum in hopes of increasing the number of undergraduates who pursue professional graduate degrees. Our hopes are that investing in transformative changes in the classrooms and providing high-quality educational opportunities will increase the time our students devote to STEM career development and ultimately result in large-scale economic development on the Southern Appalachian community.
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Melkerson, Sandra. "Diamanttetras utforskande beteende och stimformation i artificiell miljö : En jämförelse mellan odlade och vildfångade diamanttetror." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-77515.
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De har gjorts få studier på akvariesfiskars beteende. För att bemöta intresset för akvariefiskar så behöver vi veta mer om deras beteende i en artificiell miljö. Syftet med den här studien är att jämföra det utforskande beteendet hos vildfångade och odlade diamanttetror som är en vanlig akvariefisk. Hypotesen är att det finns en skillnad i deras beteende där vildfångade är mer djärva än de odlade. Grupper om fem individer av diamanttetra vildfångade och odlade släpptes ner i en ny artificiell miljö. De filmades i 20 minuter från de att de släpptes i. Testet upprepades 10 gånger med nya individer och för varje försök togs tiden det tog för varje individ att lämpa botten av akvariet och sedan mättes storleken på stimmen för varje grupp. Jag hittade en skillnad i hur lång tid fiskarna tog på sig för att lämna botten men det var ingen skillnad i höjd eller längd på stimmen. Detta visar att de vildfångade visade ett djärvare beteende än de odlade genom att lämna botten snabbare. Den här studien gav information om skillnaden i beteende för vildfångade och odlade diamanttetror och informationen kan användas för fortsatta studier kring akvariefisk.The behaviour of ornamental fish is not well studied. To meet the needs of ornamental fish hobbyists, we need to know more about the behavior of fish in artificial environments. The aim of this study is to compare the explorative behaviour of wild-captured and farmed fish in a common ornamental fish, the diamond tetra. The hypothesis is that there is a difference between the two groups behavior where the wild-captured tetras are bolder. Groups of five individuals of farmed respectively wild-captured diamond tetra were released in a new artificial environment where they were monitored for 20 minutes. The test was repeated 10 times with new individuals, and the time it took for them to leave the bottom of the aquarium was measured as well as the size of the shoal. I found a difference in the time it took for the individuals to leave the bottom, with the wild-captured tetras leaving the bottom earlier than the farmed fish. There were no differences in height or length of the shoal. Thus, the wild diamond tetra were bolder than the farmed tetras. The study gave information about the differences in behavior between wild-captured and farmed diamond tetra and can give information to further studies about ornamental fish.
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Moon, Bok Hee. "A study of the activity and characteristics of superoxide dismutase in the male reproductive parts of Petunia : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Plant Biotechnology in the School of Biological Sciences, University of Canterbury /." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/1326.
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In the stamen (male reproductive tissue) of petunia 'Hurrah' flowers, the occurrence of SOD (superoxide dismutase) provided an effective anti-oxidative mechanism against superoxide production. Superoxide production and SOD activities at five developmental stages showed a positive correlation. The highest superoxide production and SOD activity in different parts of the stamen (anther, filament and pollen) were at stages with high metabolic activity: (i) during growing buds (in anthers and filaments) (ii) when flowers with predehiscent anthers were fully open (in pollen). In all parts of the stamen, SOD activity was the lowest at stage five (fully open flowers with dehiscent anthers), superoxide production was also lower at this stage with the exception of the pollen. The highest SOD activity was localized in anthers with the pollen, suggesting that the filaments only have a structural support function. SOD was examined on a native PAGE with regard to the isozymes present within the stamen of five developmental stages. Three isozymes, which were identified as Mn SOD, Fe SOD and Cu/Zn SOD by reactions with inhibitors, were commonly found at five developmental stages in crude extracts of anthers, filaments and pollen. The developmental stages with stronger isozyme bands on the native PAGE were consistent with the stages with higher SOD activities, and the Mn SOD and Fe SOD isozyme bands were more intense than Cu/Zn SOD bands, suggesting the activities of Mn SOD and Fe SOD in the crude extracts were much higher than Cu/Zn SOD. SOD from 1,000 stamens of dehiscent mature flowers was partially purified using ammonium sulphate fractionation and DEAE cellulose column chromatography. The purified bound fraction contained only one SOD isozyme on a native PAGE, which was shown to be a Mn SOD, as it is sensitive to neither hydrogen peroxide nor cyanide. The specific activity of the purified SOD was 66.5 U/mg and the yield of total activity was 3.0%. The progress of enzyme purification was monitored using SDS-PAGE and the bound fraction contained two major polypeptide bands. The purified enzyme activity was optimal in the range of neutral pH, but it was the highest at pH 7.8. Through incubation at various pH levels for 24 hours, favourable stability of the purified fraction was confirmed around a pH range of 7 to 8.5. The purified enzyme retained 87% of its initial activity at -20 ? after one month of storage, but at 4 ? only 38% of the initial activity remained after the same period of storage.
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Carter, Lisa, Devaiah P. Shivakumar, and Cecelia A. McIntosh. "Mutagenesis of a Flavonol- 3-O-Glucosyltransferase and the Effect on Enzyme Function." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/349.
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Flavonoids are an important group of secondary metabolites found in plants and have a wide variety of properties. Some play a role in fl ower pigmentation, while others have antimicrobial properties. Glucosylation is an important modifi cation of fl avonoids and is mediated by glucosyltransferases. In this process, the enzyme transfers glucose from UDP-glucose to a specifi c position on the fl avonoid. Previous study from the lab characterized a glucosyltransferase from C. paradisi that is fl avonol specifi c. In this study an attempt has been made to study the structure and function of this fl avonol specifi c glucosyltransferase using site directed mutagenesis. The glutamine residue at position 87 of the Cp-3-O-GT enzyme was changed to isoleucine, the analogous residue in the 3-O-glucosyltransferase of Clitoria ternatea. Similarly, the histidine at position 154 was changed to tyrosine. We hypothesize that these mutations will change substrate specifi city. The glutamate at position 88 was changed to an aspartic acid. We hypothesize that this will change the regiospecifi city of the enzyme, as aspartic acid is the analogous residue found in some 7-O-glucosyltransferases. Finally, we introduced a double mutation with glutamine 87 becoming isoleucine and glutamate 88 becoming aspartic acid, with the hypothesis that both regiospecifi city and substrate specifi city will be changed.
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Kandel, Sangam, Sarah Khaja, Shiva K. Devaiah, and Cecelia A. McIntosh. "Effect of Mutant P145T on the Enzyme Activity of Glucosyltransferase from Citrus paradisi." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/353.
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Flavonoids are the C-15 phenolic compounds containing two phenyl rings and a heterocyclic ring. The majority of the flavonoids accumulated in grapefruit are flavonol, flavanone, flavone, dihydroflavonol, and chalcone glycosides. Most flavonoids are present in glucosylated form and the glucosylation is mediated by a class of enzymes called glucosyltransferases that transfer glucose from a high energy sugar donor to the acceptor aglycone at a particular position. A clone encoding a flavonol-specific 3-O-glucosyltransferase (Cp-3-O-GT) from Citrus paradisi has been previously characterized in our lab. The study of structure and function of flavonoid GTs is an important aspect of our research that contributes to the synthesis of novel glucosides by changing the glucosylation patterns of GTs. Our study focuses on the structural and functional analysis of Cp-3-O-GT through site directed mutation and analysis of mutated enzyme in terms of substrate specificity and regiospecificity. Multiple sequence alignment and homology modeling was used to identify candidate areas for mutation. For this study, Cp-3-O-GT was modeled with a flavonoid 3- O-GT from Vitis vinifera (VvGT) that can glucosylate both flavonols and anthocyanidins. We identified a proline residue at position 145 of Cp-3-O-GT that corresponded to a threonine residue in VvGT and designed a Cp-3-O-GT – P145T mutant to test the hypothesis that that mutation of key amino acid residues (proline) in Cp-3-O-GT by position specific amino acids of VvGT (threonine) could alter substrate specificity or regiospecificity of Cp-3-O-GT. Initial screening results suggested that the mutant P145T glucosylates flavanones and flavones in addition to flavonols. This is significant because flavanones and flavonols do not contain a 3-OH group for glucosylation. HPLC was performed to identify the reaction products. Early results indicate that the P145T mutant glucosylates naringenin at 7-OH position forming naringenin-7-O-glucoside and this is being confirmed. Product identification with other substrates is also being conducted. Results are being used to revisit and refine the structure model.
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Hansson, Emily. "Elevers röster gällande Hållbar utveckling." Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-34543.
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The concept Sustainable Development has a prominent role in today’s Swedish curricula for biology, geography, domestic science, chemistry and physics. The 20 years that education for sustainable development has been under discussion has resulted in many different interpretations of how the content takes shape when put into education. In this study I will discuss and examine some of these interpretations by recording interviews where students talk about and discuss sustainable development under influence of pictures and videos within the subject. The prior research presented show both critical but also constructive aspects on Teaching for Sustainable Development, and these will be put into relation to the statements the pupils who participated in this study expressed.
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Birchfield, Aaron, and Cecelia A. McIntosh. "Crystallization of a Flavonol-Specific 3-O-Glucosyltrasnferase found in Citrus paradisi." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/365.
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Citrus and other fruits produce secondary metabolites that are synthesized, regulated, and modified in part by a class of enzymes called glycosyltransferases. This class of enzymes is of substantial interest to this lab due to their unique structural and functional properties. Glycosides of flavonoids produced by glycosyltransferases have emerged in recent years as a critical part of plant metabolism, thus impacting every aspect of their growth, cultivation, production, and utilization. One such glycosyltransferase, found in Duncan Grapefruits (Citrus paradisi), was previously identified, recombinantly expressed, and shown through biochemical characterization to exclusively glycosylate the flavonol class of flavonoids. The structural basis that accounts for a glycosyltransferase's selectivity has been determined by protein crystallization in other labs, yet no structural basis currently exists for the specificity exhibited by this flavonol-specific glycosyltransferase. Currently, the WT enzyme and two mutants were expressed in E. coli, where they underwent site-directed mutagenesis to insert thrombin cleavage tags for removal of protein purification vectors, with the goal of transforming into yeast for adequate protein production. Subsequent purification and crystallization screens will allow for formation and acquisition of glycosyltransferase crystals, whose x-ray diffraction patterns will be decoded, thus revealing the enzyme's complete structure. We hypothesize that obtaining a crystal structure for this enzyme will illuminate the structural basis of its specificity. Additionally, we hypothesize that a thrombin- cleavage gene vector inserted for removal of purification tags will have no impact on enzyme activity or specificity.
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McIntosh, Cecilia A. "Structure and Function of Flavonoid Glucosyltransferases: Using a Specific Grapefruit Enzyme as a Model." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/355.
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Glucosyltransferases (GTs) are enzymes that enable transfer of glucose from an activated donor (UDP-glucose) to the acceptor substrates. A flavonol specific glucosyltransferase cloned from Citrus paradisi has strict substrate and regiospecificity (Cp3OGT). The amino acid sequence of Cp3OGT was aligned with a purported anthocyanin GT from Clitorea ternatea and a GT from Vitis vinifera that can glucosylate both flavonols and anthocyanidins. Using homology modeling to identify candidate regions followed by site directed mutagenesis, three double mutations of Cp3OGT were made. Biochemical analysis of the three mutant proteins was performed. S20G+T21S protein retained activity similar to the wildtype (WT- Kmapp-80 µM; Vmax = 16.5 pkat/µg, Mutant- Kmapp-83 µM; Vmax -11 pkat/µg) but the mutant was more thermostable compared to the WT and this mutation broadened its substrate acceptance to include the flavanone, naringenin. S290C+S319A mutant protein retained 40% activity relative to wildtype, had an optimum pH shift, but had no change in substrate specificity (Kmapp-18 µM; Vmax-0.5 pkat/µg). H154Y+Q87I protein was inactive with every class of flavonoid tested. Product identification revealed that the S20G+T21S mutant protein widened the substrate and regio-specificity of CP3OGT. Docking analysis revealed that H154 and Q87 could be involved in orienting the ligand molecules within the acceptor binding site. H363, S20, and S150 were also found to make close contact with the 7-OH, 4-OH and 3’-OH groups, respectively.
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McIntosh, Cecilia A. "Structure and Function of Flavonoid Glucosyltransferases: Using a specific Grapefruit Enzyme as a Model." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/369.
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Bellamy, Stephen, and steve bellamy@flinders edu au. "RESOURCE PARTITIONING BETWEEN TWO SYMPATRIC AUSTRALIAN SKINKS, EGERNIA MULTISCUTATA AND EGERNIA WHITII STEPHEN BELLAMY Thesis submitted in total fulfilment of the requirements of the degree of Doctor of Philosophy AUGUST 2006 SCHOOL OF BIOLOGICAL SCIENCES FLINDERS UNIVERSITY, ADELAIDE, SOUTH AUSTRALIA ________________________________________." Flinders University. Biological Sciences, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20070124.145924.
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When species compete for resources, in a stable homogeneous environment, there are two possible outcomes. The first is that one species will out-compete the other and exclude it from the environment. This is known as the competitive exclusion principle. The second is that both species will manage to coexist. Coexistence can only occur if the species niches are differentiated such that interspecific competition is minimised, or eliminated. This outcome is known as resource partitioning.
Two closely related Australian skink species of the Egernia genus, Egernia multiscutata and Egernia whitii, are abundant and sympatric on Wedge Island in South Australias Spencer Gulf. The species are morphologically very similar and appear to have very similar life histories and habitat requirements. Ostensibly, they would compete for limiting resources in this environment.
This thesis is the first investigation into resource partitioning in this previously unstudied model organism. I report the results of multi-faceted investigations into the coexistence of the skinks, E. multiscutata and E. whitii on Wedge Island and the evidence for, and mechanisms of, any facultative resource partitioning between them.
Study methods involved a transect survey of most of Wedge Island to determine the species distributions and any evidence for resource partitioning; a morphological comparison to investigate any potential competitive advantages of either species; a habitat choice experiment to establish retreat-site preferences in the absence of interspecific interference; and, a series of staged dyadic encounter experiments to investigate interspecific competitive interactions.
Resource partitioning was evidenced by differential distributions of the species among substrates containing the elements required for permanent refuge shelters. This partitioning was not mediated by avoidance of particular substrates but by the presence of the opponent species, combined with attraction to suitable substrates. Asymmetries in some morphological characters were found to confer a potential competitive advantage to E. multiscutata in agonistic encounters with E. whitii. Both species were found to have the same refuge site preferences when interference competition was experimentally removed. This result was not concordant with observed resource partitioning in the field and suggests that the habitat choices of both species are modified by the presence of the opponent species. Analyses of staged dyadic encounter experiments showed that E. multiscutata was more likely to gain greater access to a contested habitat resource and more likely to exclude E. whitii from the resource than vice-versa. Nevertheless, the outcome of competitive interactions was not completely deterministic and there was some tolerance of co-habitation. E. multiscutatas competitive advantage was attributable largely to its greater mass and head dimensions relative to snout to vent length. However, differential behavioural responses to the threat of larger opponent size also played an important part in resource partitioning between the species.
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Alviso, Frank. "The role of inhibitory control, maternal sensitivity, and attachment security in the development and maintenance of self-regulation." Scholarly Commons, 2013. https://scholarlycommons.pacific.edu/uop_etds/119.
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The present study investigated the interrelationships between various constructs drawn from the attachment, temperament, and neuropsychology frameworks in the context of self-regulation development and maintenance. In particular, the study sought to determine whether attachment security in early childhood was a predictor of self-regulation and social competence in adolescence, and to elucidate the roles of inhibitory control (IC), maternal sensitivity, and self-control in this relationship. Structural equation modeling was used to create an integrated theoretical developmental model of self-regulation. Attachment Security at 24 months was found to be a significant predictor of Social Skills at age 15 years. In addition, IC at 54 months, Maternal Sensitivity during third grade, and Self-Control during 4 th grade, were found to be subsequent partial mediators of this relationship. Overall, results of the study suggest that foundational self-regulatory capacities such as inhibitory control evolve from patterns of sensitive caregiver-child interactions in early attachment relationships. Furthermore, these capacities appear to be maintained in part through sensitive caregiving throughout childhood and into mid-adolescence. Additional implications of these results for integrating concepts of divergent theoretical domains are also discussed.
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Devaiah, Shivakumar P., and Cecelia A. McIntosh. "Site-Directed Mutational Analysis of Flavonol 3-0-Glucosyltransferases from Citrus paradisi." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/340.
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Glucosyltransferases (GTs) are the important group of enzymes which facilitates the incorporation of UDPactivated glucose to a corresponding acceptor molecule through glucosylation. Glucosylation is a common alteration reaction in plant metabolism and is regularly associated with the production of secondary metabolites. Glucosylation serves a number of roles within metabolism including: stabilizing structures, affecting solubility, transport, and regulating the bioavailability of the compounds for other metabolic processes. GTs involved in secondary metabolism share a conserved 44 amino acid residue motif (60–80% identity) known as the plant secondary product glucosyltransferase (PSPG) box, which has been demonstrated to include the UDP-sugar binding moiety. Among the secondary metabolites, flavonoid glycosides affect taste characteristics in citrus making the associated glucosyltransferases particularly interesting targets for biotechnology applications in these species. Custom design of enzymes requires understanding of structure/function of the protein. The present study focuses on creating mutant Flavonol- 3-O- Glucosyltransferases proteins using site-directed mutational analysis and testing the effect of each mutation on substrate specificity and kinetic properties of the enzyme.
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Wamucho, Anye, Deborah Hayford, and Cecelia A. McIntosh. "Heterologous Expression of Grapefruit Clones PGT3 and PGT9 in Yeast and Screening of Recombinant Protein for Activity." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/336.
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The wide diversity of plant secondary products results from different modifications undergone during biosynthesis, including glucosylation. These modification reactions result in production of the compounds actually found in plants and to unique chemical and biochemical properties, including some bitter compounds in grapefruit. While the presence of a PSPG box motif allows for identification of a clone as a putative glucosyltransferase (PGT), diversity of GT primary structures makes it difficult to accurately assign specific function. Our approach is to identify and isolate putative GT clones, express them heterologously, and biochemically characterize the proteins. Eleven putative GT clones have been isolated from Citrus paradise and some have been biochemically characterized. The current hypothesis being tested is that PGT3 and PGT9 clones are plant secondary product GTs. Due to issues with inclusion bodies when using E. coli, proteins were expressed in Pichia pastoris using the pPICZA vector. Recombinant protein expression was confirmed by Western blot and proteins were enriched by IMAC. Over 30 flavonoid and simple phenolic substrates, representing many compounds found in grapefruit, were screened for activity with PGT3 and PGT9 proteins. No significant activity was found and the biochemical function of the proteins encoded by these clones will be further investigated.
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McIntosh, Cecilia A. "Supporting Students’ Writing and Degree Completion: Boot Camps, Write-Ins and Writing Retreats." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/370.
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Mogren, Anna. "Implementering av lärande för hållbar utveckling : En studie av rektors förståelse av kvalitet i skolans organisation." Licentiate thesis, Karlstads universitet, Institutionen för miljö- och livsvetenskaper (from 2013), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-64659.
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Student outcomes of Education for Sustainable Development (ESD) is reported to be weak and empirical studies investigating the underlying causes have been called for. School organization is pointed out as essential, which highlights the role of school leaders in realizing ESD. This study aims to identify characteristic features of ESD active school organizations, by investigating how school leaders maintain high quality in their organizations. ESD is thus studied from an internal organizational perspective. Fourteen school leaders at ten upper secondary schools, active in ESD implementation, were interviewed and qualitative data quantified. A special focus was on school leaders’ transformative statements, in response to earlier criticism that ESD implementation has been too structural. Results consist of 26 identified quality criteria. By means of cluster analysis, the quality criteria were merged into four principal quality criteria: collaborative interaction and school development, student-centred education, cooperation with local society and proactive leadership and continuity. The school leaders’ quality strategies were identified through correlation analysis of their principal quality criteria. The quality strategies reveal a difference in the schools’ internal or external focus. An analysis of the school leaders’ quality statements in relation to their quality strategy implementation indicates that ESD to a large degree is introduced from a transformative perspective. One school in the study stands out as highly transformation-oriented, and has a quality strategy combining an internal and external focus, thus making it a possible benchmark for successful ESD-implementation. The study contributes a suggestion on how a progression of ESD implementation can take place and as well as possible obstacles.Studier om implementering av Lärande för hållbar utveckling (LHU) visar att påverkan på elevers förståelse, attityder och agerande i frågan är liten. Det finns ett behov av att empiriskt undersöka hur skolans organisation kan underlätta en mer framgångsrik LHU implementering. Rektorernas roll pekas ut som central i det arbetet, men få studier har tidigare undersökt hur rektorer arbetar med skolorganisationen. I studien undersöks generella uttryck för kvalitet som rektorer anser viktiga i skolorganisationen för att åstadkomma en utbildning med hög kvalitet. Resultaten tolkas i ljuset av skolor som aktivt implementerar LHU. Studien söker svar på vad som utmärker de skolorganisationer som aktivt arbetar med LHU. 14 rektorer på 10 LHU-skolor har intervjuats. Kvalitativ data har kvantifierats i syfte att upptäcka mönster och sammanhang. Ett speciellt fokus har ägnats åt transforamtiva uttryck, som ett svar på tidigare kritik mot att LHU implementerats allt för strukturellt inom skolan. Resultaten redovisar kvalitetskriterier som rektorerna framhåller som viktiga samt specifika fokusområden för kvalitetsarbete. Skolor i studien med hög medvetenhet om transformativa uttryck inom skolans organisation utgör grund för en diskussion om hur strategier för LHU implementering kan utformas.
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Sposito, Neusa Elisa Carignato. "Estágio supervisionado de Ciências Biológicas : aproximações entre o legal e o real /." Bauru : [s.n.], 2009. http://hdl.handle.net/11449/102020.
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Orientador: Ana Maria de Andrade CaldeiraBanca: Álvaro Lorencini Júnior
Banca: Nelson Antonio Pirola
Banca: Celi Rodrigues Chaves Dominguez
Banca: Renato Eugênio da Silva Diniz
Resumo: Este estudo trata do estágio supervisionado realizado por dezenove licenciandos do Curso de Licenciatura de Ciências Biológicas, da UNESP - Bauru, no segundo semestre de 2006 em três diferentes Escolas de Educação Básica, públicas. O objetivo da pesquis foi verificar se a efetivação do estágio supervisionado poderia ocorrer em atendimento às determinações das Diretrizes Curriculares Nacionais para a Formação de Professores (DCNs) no que se refere à parceria entre as instituições formadoras: a Universidade e a Escola de Educação Básica. Essa legislação propõe um acordo preliminar entre as diferentes instituiçõe de ensino e, em decorrência desse acordo, a elaboração de um projeto de estágio com ações de mútua colaboração entre elas. Há necessidade de se pesquisar sobre esse assunto, em especial na Licenciatura em Ciências Biológicas, diante do pouco que foi publicado até agora, em virtude de a lei estar em fase de implementação, por exemplo. A presente pesquisa teve três etapas: a preliminar (momento da apresentação da pesquisadora às duas diretoras e uma vice-diretora das três escolas de educação básica do estágio supervisionado propriamente dito, envolvendo os licenciandos, as professoras, os alunos das escolas públicas, as diretoras, vice-diretora e coordenador pedagógico) e a final (período de encerramento, com uma avaliação escrita feita pelos licenciados sobre o estágio realizado). Trata-se de pesquisa qualitativa que se assemelha ao estudo de caso e está fundamentada em uma das modalidades da investigação qualitativa apresentada por Flick (2004), que se refere à construção e à compreensão de textos a partir da experiência realizada, ou seja, da pesquisa. Os instrumentos de coleta de dados foram: gravações, relatórios, anotações, questionários. Além das DCNs, os autores que sustentam esse trabalho são:... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This study treats about the supervised student teaching practiced by nineteen majoring students of the Major Biological Sciences Course of UNESP - Bauru, on the second semester of 2006 in three different Schools of Basic Education, public ones. The objective of the research was to verify if the effectuation of the supervised student teaching could occur according to the determinations of the National Curricular Directives for the Graduation of Teachers (DNCs) on what is referred to the partnership between graduating institutions: the University and the School of Basic Education. This legislation proposes a preliminary agreement between the different teaching institutions and, as result of this agreement, the elaboration of a student teaching project with cooperative actions between them. There is a research need about this subject, especially on Majoring on Biological Sciences, in front of what was published so far, in the fact of the law being under implementation, for example. The present research had three stages: the preliminary (moment of the introduction of the researcher to the two principals and one vice-principal of three schools of basic education with supervised student teaching centered on the partnership between institutions), intermediary (stage of carrying out the supervised student teaching, involving the majoring students, teachers, students of publi schools, principals, vice-principal and pedagogical counselor) and final (period of conclusion, with a writing evaluation made by the majoring students about the student teaching accomplished). It is a qualitative research similar to the case study and is based upon one of the forms of qualitative investigation presented by Flick (2004), which refers to the text construction and comprehension starting from the accomplished experience, which means, the research. The instruments of data collection were: records, reports... (Complete abstract click electronic access below)
Doutor
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Kandel, Sangam, Devaiah P. Shivakumar, and Cecelia A. McIntosh. "Biochemical Characterization of a Cp-3-O-GT Mutant P145T and Study of the Tags Effect on GT Activity." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/361.
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Glucosyltransferases catalyze glucosylation by transferring glucose from UDP-activated sugar donor to the acceptor substrates. This research is focused on the study of the effect of a single point mutation on enzyme activity, characterization of a flavonol specific 3-Oglucosyltransferase (Cp-3-O-GT) mutant- P145T, and further modification of the clone to cleave off tags from recombinant wild type and P145T mutant proteins in order to crystallize the proteins. Multiple sequence alignment and homology modeling was done to identify candidate residues for mutation. Cp-3-O-GT was modeled with a flavonoid 3-O-GT from Vitis vinifera (VvGT) that can glucosylate both flavonols and anthocyanidins. We identified a proline residue at position 145 of Cp-3-O-GT that corresponded to a threonine residue in VvGT and designed a Cp-3-O-GT- P145T mutant to test the hypothesis that that mutation of proline by threonine in Cp-3-O-GT could alter substrate or regiospecificity of Cp-3-O-GT. While the mutant P145T enzyme did not glucosylate anthocyanidins, it did glucosylate flavanones and flavones in addition to flavonols. This is significant because flavanones and flavones do not contain a 3-OH group. HPLC was performed to identify the reaction products. Early results indicated that the mutant protein glucosylates naringenin at the 7-OH position forming prunin. Results are being used to revisit and refine the structure model. In other related work, a thrombin cleavage site was inserted into wild type and recombinant P145Tenzyme and we are currently working on transformation into yeast for recombinant protein expression. Cleaving off tags is a pre-requisite to future efforts to crystallize the proteins. Solving the crustal structures will make a significant contribution to the structural and functional study of plant flavonoid GTs in general and Cp-3-O-GT in particular.
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Spaulding, Nathan, Devaiah P. Shivakumar, and Cecelia A. McIntosh. "Effect of the Mutation D344P on the Regio and/or Stereospecificity of Cp3-O-Gt." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/362.
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Plants produce a vast array of secondary metabolites. The phenolic compounds flavonoids are ubiquitous among plants and are known to aid in processes such as plant reproduction, UV defense, pigmentation and development. In relation to human health, flavonoids have also been found to possess anti-inflammatory, anti-cancer, and anti-oxidant properties. Flavonoids ability to participate in so many interactions is due in part to their subclass variation and further chemical modification. One such modification is glucosylation, where a glucose molecule is added to the flavonoid substrate, reactions catalyzed by glucosyltransferases. Citrus paradise contains a glucosyltransferase that is specific to the 3-O position of flavonols. To further understand the reactions it catalyzes, Cp3-O-GT structure was modelled against an anthocyanidin/flavonol 3 GT found in Vitis vinifera to identify candidate amino acids for mutations. Mutants were then created using site-directed mutagenesis, and one mutant, D344P, was constructed by an aspartate being replaced with a proline based off of the sequence comparison of the original enzymes. Biochemically characterizing the mutant D344P protein will determine whether the mutation has an effect on the regio and/or steriospecificity of Cp3-OGT. An initial screening assay has been performed using radioactive UDP-glucose as a sugar donor. Early results indicated that the mutant D344P has particular affinity for flavonols and for diosmetin, a flavone. Kinetic assays are being performed to confirm these results. Studies of time course, enzyme concentration, HPLC product analysis, pH optimum and reaction kinetics will be performed to further complete D344P protein characterization.
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Gullberg, Anna. "Processinriktat och resultatinriktat motivationsklimat på svenska och spanska högstadieskolor." Thesis, Malmö högskola, Lärarutbildningen (LUT), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-34159.
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Studien processinriktat och resultatinriktat motivationsklimat på svenska och spanska högstadieskolor undersöker skillnader och likheter inom processinriktat och resultatinriktat klimat. I denna studie undersöks det hur dessa två klimat ser ut på svenska och spanska skolor och detta ur svenska och spanska idrottslärares perspektiv. I studien används Nicholls (1989) teori om de två motivationsklimaten. Empirin är inhämtad via semistrukturerade intervjuer med idrottslärare på tre svenska och tre spanska högstadieskolor. Detta i kombination med Nicholls (1989) teori och andra modeller, ligger till grund för den senare gjorda analysen. Studien kommer till slutsatsen att spanska skolor är mer resultatinriktade medan svenska skolor är mer processinriktade.The Study mastery and performance motivational climate, a comparison study between secondary schools in Sweden and Spain, examine the mastery orientation and performance orientation. The aim with the study is find out what motivational climate, mastery or performance that is used by physical educators. The theory, Nicholls (1989) theory about the two motivational climates; mastery orientation and performance orientation is used in this study. The empirical data has been collected through semi-structured interviews with teachers at three secondary schools in Sweden and three secondary schools in Spain. This combined with theory and models will be the underlying material to the later analysis. The study will come to the conclusion that Spanish schools are more performance orientated than the Swedish schools which tend to be more mastery orientated.
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Santana, Salete de Lourdes Cardoso. "UTILIZAÇÃO E GESTÃO DE LABORATÓRIOS ESCOLARES." Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/6654.
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The scenario of Brazilian education has been improving year on year, according to official figures. However, with regard to the teaching of science and practical classes, especially in public schools, there is still a long way to go. In view of this, and seeking help to illustrate the current state of public schools regarding the existence and use of school laboratories, whether in science or computer, we proposed that this work aims to: make a diagnosis of the situation of public schools elementary schools in the cities of Barra do Quaraí and Uruguaiana located on the western border of Rio Grande do Sul, in relation to the presence and use of school laboratories, both computer science and propose the effective use of space, especially the science lab, suggesting appropriate management techniques and waste treatment practices from lessons and suggest the implementation of a project for a science lab in the School Hall Elementary School October 22, located in Barra do Quaraí. To perform the first phase were carried out visits to 35 schools, state and municipal, urban and rural areas. During his visit to the 1430 questionnaire were applied students, 46 teachers and 37 administrators. Of all the schools surveyed, was found the following situation: have 16 science lab and computer lab are 34 (only one state school does not have either). Where permitted, the spaces were visited in order to see the facilities and infrastructure. With the data collected it was possible to detect positive and negative aspects of the use or nonuse of the laboratories for each category, as well as evaluating the importance of these activities and these spaces represent the school life of students and the group of teachers and administrators. These data served as a basis for the production of the second phase, which was the production of two booklets, one containing the proposal and suggested the use of experimental activities and the other dealing with the issue of waste and safety when conducting the practical classes. The third phase involved the preparation of the proposed deployment of the laboratory. The data analysis, and result in a manuscript, also allowed to profile all those involved in research as well as the vision of the same when it comes to practical classes. Thus, the booklets are a way to encourage the use of laboratories and assist teachers in planning classroom practices. Also, addressing the issue of waste, we seek to answer questions about the proper disposal of waste and waste resulting from the experimental activities. Each of the materials produced with this work counts as a contribution and response to each school that agreed to participate.O cenário da educação brasileira vem melhorando ano a ano, conforme os índices oficiais. Entretanto, no que se refere ao ensino de ciências e aulas práticas, especialmente nas escolas públicas, ainda há um longo caminho a percorrer. Em vista disso, e buscando contribuir para ilustrar a situação atual das escolas públicas no que tange à existência e uso dos laboratórios escolares, sejam eles de ciências ou de informática, propusemos este trabalho que tem como objetivos: elaborar um diagnóstico da situação das escolas públicas de ensino fundamental nas cidades de Uruguaiana e Barra do Quaraí, localizadas na fronteira oeste do Estado do Rio Grande do Sul, no que se refere à presença e uso de laboratórios escolares, tanto de ciências quanto de informática, propor a utilização efetiva dos espaços, especialmente do laboratório de ciências, sugerindo técnicas adequadas de gestão e tratamento de resíduos oriundos das aulas práticas e sugerir a implantação de um projeto de um laboratório de ciências na Escola Municipal de Ensino Fundamental 22 de Outubro, localizada na cidade de Barra do Quaraí. Para realização da primeira fase foram realizadas visitas a 35 escolas, estaduais e municipais, de zona urbana e rural. Durante essa visita foram aplicados questionários a 1430 alunos, 46 professores e 37 gestores. Do total das escolas pesquisadas, foi encontrada a seguinte situação: 16 possuem laboratório de ciências e 34 possuem laboratório de informática (somente uma escola estadual não apresenta nenhum dos dois). Sempre que permitido, foram visitados os espaços com a finalidade de conhecer as instalações e infraestrutura. Com os dados coletados foi possível detectar aspectos positivos e negativos do uso ou não dos laboratórios para cada categoria, bem como avaliar a importância que essas atividades e esses espaços representam na vida escolar dos alunos e para o grupo de professores e gestores. Tais dados serviram também de subsídios para a elaboração da segunda fase, que foi a confecção de duas cartilhas, uma contendo a proposta de uso e sugestão de atividades experimentais e outra tratando a questão dos resíduos e da segurança durante a realização das aulas práticas. A terceira fase compreendeu a elaboração da proposta de implantação do laboratório. A análise dos dados, além de resultar em um manuscrito, também permitiu traçar o perfil de todos os envolvidos na pesquisa, bem como da visão dos mesmos no que tange às aulas práticas. Sendo assim, as cartilhas representam um meio de incentivar o uso dos laboratórios e auxiliar os professores no planejamento das aulas práticas. Igualmente, abordando a questão dos resíduos, busca-se sanar dúvidas quanto à eliminação correta dos resíduos e rejeitos que resultam das atividades experimentais. Cada um dos materiais produzidos com a realização deste trabalho conta como contribuição e resposta a cada escola que aceitou participar da pesquisa.
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Coupaud, Magali. "Evolution du vivant et hasard : étude quantitative des conceptions d'élèves de collège dans le contexte français." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0205/document.
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L’évolution du vivant est un concept majeur pour les sciences biologiques contemporaines, mais également un objet d’enseignement complexe. En France, l'évolution du vivant est introduit dès l’école primaire. Cet enseignement ne devient explicite qu’en fin de la scolarité obligatoire. Cette étude vise à mieux comprendre comment les conceptions de collégiens français sur l’évolution du vivant se modifient tout au long du collège et comment leurs conceptions du hasard peuvent influencer leur acceptation et leur compréhension de ce concept. Pour cela, un questionnaire, UnRESt est élaboré et permet d’étudier les conceptions de plus de 1600 collégiens de l'évolution du vivant et du hasard, et d’établir les relations éventuelles entre ces deux types de conceptions. Il est construit sur la base des résultats obtenus dans des études exploratoires (questionnaire ouvert, discussion à visée philosophique). L’étude révèle que, quel que soit le niveau de classe, la moitié des collégiens interrogés acceptent l’évolution du vivant, et un tiers d’entre eux semblent avoir une compréhension en désaccord avec une pensée évolutionniste. Selon les espèces étudiées, une vision explicative 'transformiste' subsiste chez les élèves. L’étude révèle également que l’acceptation et la compréhension de l’évolution du vivant sont en lien avec les conceptions du hasard. En particulier, les résultats témoignent d’un obstacle dans l’utilisation du mot hasard au sens de contingence, ainsi qu’une influence de leur vision du hasard ‘probabliste’ sur leur compréhension des mécanismes d’évolution. Cette recherche appelle à laisser une place plus importante au hasard dans l’enseignement au collègeEvolution of living species is a major concept for the contemporary biological sciences, but also a complex object of teaching. In France, the evolution of living species starts in primary school. This teaching becomes well identified only at the end of compulsory schooling. This study aims a better understanding on the change of the conceptions of secondary school students along junior high school and how their conceptions of randomness can influence their acceptation and their understunding of this concept. Consequently, a questionnaire, UnRESt has been elaborated to study the mainstream conceptions of more than 1600 students about the evolution of living and randomness and to find potential links between these two types of conceptions. The UnRESt ingineering is based on exploratory studies (open-ended questions, philosophical discussion). The study shows that a half of the students accept the evolution of living species and a third of them seems to have an understanding in opposition with an evolutionist understanding. According to the species studied, a ‘transformist’ vision is favoured by student. They highlights also that the acceptation and the understanding of the evolution are related to the students’ conceptions of randomness. More specifically, the results show an obstacle in the use of the word randomness with the meaning of contingency and an influence of their vision of ‘probabilist’ randomness on their understanding of the evolution mechanisms. The research concludes on the place to give to the scientific concept of randomness in the teaching in secondary school
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Adepoju, Olusegun A., Devaiah K. Shiva, and Cecelia A. McIntosh. "Selected Point Mutations of a Flavonoid 3-O-Glucosyltransferase from Citrus paradisi (Grapefruit) and Effect on Substrate and Regiospecificity." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/343.
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Flavonoids are secondary metabolites that are important in plant defense, protection, and human health. Most naturally-occurring flavonoids are found in glucosylated form. Glucosyltransferases (GTs) are enzymes that catalyze the transfer of glucose from a high energy sugar donor to an acceptor molecule. At this time, it is not possible to accurately predict putative GT activity from sequence alone; biochemical characterization is critical. A flavonol-specific 3-O-GT enzyme has been identified and cloned from the leaf tissues of grapefruit. The enzyme shows rigid substrate specificity and regiospecificity. F3GTs from grape and grapefruit were modeled against F7GTs from Crocus sativus and Scrutellaria biacalensis, and several non-conservative amino acid differences were identified that may impact regioselectivity. This research is designed to test the hypothesis that specific amino acid residues impart the regiospecificity of the grapefruit enzyme. Site-directed mutagenesis was performed on three potentially key amino acid residues within the grapefruit F3-GT that were identified through homology modeling. Enzyme activity of the mutant F3-GT proteins will be analyzed for a possible change in glucosylation pattern. Other flavonoid classes will also be tested with the mutant enzymes to test for change in substrate specificity.
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Devaiah, Shivakumar P., and Cecelia A. McIntosh. "Expression and Biochemical Characterization of Two Glucosyltransferases from Citrus paradisi." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/335.
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Glucosylation is a common alteration reaction in plant metabolism and is regularly associated with the production of secondary metabolites. Glucosylation serves a number of roles within metabolism including: stabilizing structures, affecting solubility, transport, and regulating the bioavailability of the compounds for other metabolic processes. The enzymes that lead to glucoside formation are known as glucosyltransferases (GTs), and characteristically accomplish this task by transferring a UDP-activated glucose to a corresponding acceptor molecule. GTs involved in secondary metabolism share a conserved 44 amino acid residue motif (60–80% identity) known as the plant secondary product glucosyltransferase (PSPG) box, which has been demonstrated to include the UDP-sugar binding moiety. Among the secondary metabolites, flavonoid glycosides and limonoid glycosides affect taste characteristics in citrus making the associated glucosyltransferases particularly interesting targets for biotechnology applications in these species. The research focus of our lab is to establish the function of putative secondary product glucosyltransferase clones identified from Citrus paradisi. In the present study, we report on the activity and biochemical characterization of two clones, PGT 7 (Flavonol-3-O-GT) and PGT8 (Limonoid GT) which were expressed in Pichia pastoris.
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Adepoju, Olusegun A., Devaiah K. Shiva, and Cecelia A. McIntosh. "Selected Point Mutation of a Flavonoid 3-0-Glucosyltransferase from Citrus paradisi (Grapefruit) and its Effect on Substrate and Regiospecificity." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/339.
Full textAbstract:
Flavonoids are secondary metabolites that are important in plant defense, protection, and human health. Most naturally-occurring flavonoids are found in glucosylated form. Glucosyltransferases (GTs) are enzymes that catalyze the transfer of glucose from a high energy sugar donor to an acceptor molecule. At this time, it is not possible to accurately predict putative GT activity from sequence alone; biochemical characterization is critical. A flavonol-specific 3-O-GT enzyme has been identified and cloned from the leaf tissues of grapefruit. The enzyme shows rigid substrate specificity as well as regiospecificity. Several F3GT's characterized from other plants also had the ability to glucosylate anthocyanidins, however the grapefruit F3GT did not. This research is designed to test the hypothesis that specific amino acid residues impart the substrate specificity and regiospecificity of the grapefruit enzyme. Site-directed mutagenesis was performed on three potentially key amino acid residues within the grapefruit F3-GT that were identified through homology modelling. Enzyme activity of the mutant F3-GT proteins will be tested with flavonols for a possible change in glucosylation pattern. Other flavonoid classes will also be tested with the mutant F3-GT enzyme to test for change in substrate specificity. The result from this study will add to our knowledge of GTs.
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Stewart, Matthew Blair. "Computational and experimental investigations of biologically interesting molecules." Thesis, full-text, 2009. https://vuir.vu.edu.au/1957/.
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The reconciliation of experimental and computational data is an on-going challenge in many fields of scientific enquiry. This is particularly true in chemistry, especially with respect to biologically interesting molecules, given the myriad of problems that now lend themselves to theoretical investigation. This work sampled several areas of this greater landscape using various computational methods, and compared these results to relevant, experimentally derived data.
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Devaiah, Shivakumar P., Cheng Zhang, and Cecelia A. McIntosh. "Structure and Functional Analysis of Glucosyltransferase from Citrus paradisi." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/344.
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Glucosyltransferases (GTs) are enzymes that expedite the incorporation of UDP-activated glucose to a corresponding acceptor molecule. This enzymatic reaction stabilizes structures and affects solubility, transport, and bioavailability of flavonoids for other metabolic processes. Flavonoid glycosides affect taste characteristics in citrus making the associated glucosyltransferases particularly interesting targets for biotechnology applications. Custom design of enzymes requires understanding of structure/function of the protein. The present study focuses on creating mutant flavonol-3-O-glucosyltransferase (F-3-O-GT) proteins using site-directed mutagenesis and testing the effect of each mutation on substrate specificity, regiospecificity and kinetic properties of the enzyme. Mutations were selected on the basis of sequence similarity between grapefruit F-3-O-GT, an uncharacterized GT gene in blood orange (98%), and grape F3GT (82%). Grapefruit F-3-O-GT prefers flavonol as a substrate whereas the blood orange sequence is annotated to be a flavonoid 3GT and the grape GTs could glucosylate both flavonols and anthocyanidins. Mutants of F-3-O-GT were generated by substituting L41M, N242K, E296K and N242K+E296K and proteins were expressed in Pichia pastoris using the pPICZA vector. Analysis of these mF-3-O-GTs showed that all of them preferred flavonols over flavanone, flavone, isoflavones, or anthocyanidin substrates and showed decrease in enzyme activity of 16 to 51% relative to the wild type F-3-O-GT.
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Kandel, Sangam, Sarah Khaja, Devaiah P. Shivakumar, and Cecelia A. McIntosh. "Structural and Functional Analysis of Grapefruit C-3OGT Mutant P145T." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/356.
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Flavonoids are a class of secondary metabolites, the majority of which are present in glucosylated form. Glucosyltransferases are the enzymes that mediate glucosylation by transferring glucose from a high energy sugar donor to the acceptor substrates. Our study focuses on the structural and functional analysis of a flavonol-specific 3-O-glucosyltransferase (Cp-3-O-GT) clone from Citrus paradisi that has been characterized previously in our lab. Multiple sequence alignment and homology modeling was done to identify candidate residues for mutation. Cp-3-O-GT was modeled with a flavonoid 3-O-GT from Vitis vinifera (VvGT) that can glucosylate both flavonols and anthocyanidins. We identified a proline residue at position 145 of Cp-3-O-GT that corresponded to a threonine residue in VvGT and designed a Cp-3-O-GT- P145T mutant to test the hypothesis that that mutation of proline by threonine in Cp-3-O-GT could alter substrate or regiospecificity of Cp-3-OGT. While the mutant P145T enzyme did not glucosylate anthocyanidins, it did glucosylate flavanones and flavones in addition to flavonols. This is significant because flavanones and flavonols do not contain a 3-OH group. HPLC was performed to identify the reaction products. Early results indicated that the mutant protein glucosylates naringenin at 7-OH position forming prunin. Product identification with other substrates is in progress. Results are being used to revisit and refine the structure model. Structural and functional analysis of flavonoid GTs may contribute to custom design of GTs for the synthesis of novel glucosides by changing glucosylation patterns.
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King, Kathleen, Devaiah P. Shivakumar, and Cecelia A. McIntosh. "The Effect of R382W Mutation on C. paradisi Flavonol-Specific 3-O-Glucosyltransferase." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/358.
Full textAbstract:
Flavonoids are a class of plant metabolites with C6-C3-C6 structure responsible for many biological functions, including coloration and defense. Citrus paradisi, grapefruit, contains a wide variety of flavonoids which are grouped by the extent of modification, examples of which are flavonols, flavones, and flavanones. A major modification is the addition of glucose by glucosyltransferases (GTs) to stabilize the structure and provide ease of transport. This process can be highly substrate and regiospecific. With Cp3OGT, glucose is added at the 3-hydroxy position. This 3GT only accepts flavonols as its substrate; however, a Vitis vinifera (grape) 3-GT can accept both flavonols and anthocyanidins. Homology modeling using the crystallized structure of the V. vinifera GT predicted sites of amino acids that could influence substrate binding site. The 382 position was of particular interest with arginine in C. paradisi and tryptophan in V. vinifera. This change is hypothesized to cause a shift in substrate specificity of the Cp3OGT to accept anthocyanidins as well as flavonols. Site-directed mutagenesis was performed to form the R382W mutant Cp3OGT and transformed into yeast for expression. Western blot determined the optimal protein induction period for the cells, after which the cells were broken to extract the recombinant mutant protein. Purification of the R382W 3GT allowed for enzyme analysis to be performed by measuring the incorporation of radioactive glucose into the reaction product. HPLC will be used to identify reaction products. An enzyme kinetics study will show the extent of any biochemical change in function as a result of this mutation; results will then be incorporated into a refined protein model.
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Spaulding, Nathan, Devaiah P. Shivakumar, and Cecelia A. McIntosh. "Affect of Mutation D344P on the Regio- and/or Substrate Specificity of CP3-OGT." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/360.
Full textAbstract:
Plants produce a vast array of secondary metabolites. The phenolic compounds flavonoids are metabolites ubiquitous among plants and are known to aid in processes such as plant reproduction, UV defense, pigmentation and development. In relation to human health, flavonoids have also been found to possess anti-inflammatory, anti-cancer, and anti-oxidant properties. Flavonoids ability to participate in so many interactions is due in part to their subclass variation and further chemical modification. One such modification is glucosylation, where a glucose molecule is added to the flavonoid substrate. The enzymes that catalyze these reactions are known as glucosyltransferases. Citrus paradisi contains a glucosyltransferase that is specific to the 3-O position of flavonols. To further understand the reactions it catalyzes, Cp3-O-GT structure was modeled against a anthocyanidin/flavonol 3 GT found in Vitis vinifera to identify candidate amino acids for mutations. Mutants were then created using site-directed mutagenesis, and one mutant, D344P, was constructed by an aspartate being replaced with a proline based off of the sequence comparison of the original enzymes. Biochemically characterizing the mutant D344P protein will determine whether the mutation has an effect on the regio and/or steriospecificity of Cp3-OGT. An initial screening assay has been performed using radioactive UDP- glucose as a sugar donor. Early results indicated that the mutant D344P has particular affinity for flavonols and for diosometin, a flavone. Kinetic assays are being performed to confirm these results. Studies of time course, enzyme concentration, HPLC product analysis, pH optimum and reaction kinetics will be performed to further complete D344P protein characterization.