The influence of macronutrients on cognitive performance : effects across age and task difficulty : thesis presented in partial fulfillment of the requirements for the degree of Master of Arts in Psychology at Massey University

The effects of pure glucose, protein, and fat ingestion on tasks of paragraph recall, word recall, and mental arithmetic were examined. These effects were also investigated with regard to the age of the participant and the task difficulty level. Twelve young and twelve older adults participated in the study. Over four separate morning sessions, participants ingested one of the four drinks (glucose, protein, fat, or placebo), and completed easy and hard versions of the paragraph recall word recall, and mental arithmetic tasks. The between-group factor was Age of the participant (young or older adult). The within-group factors were type of Nutrient ingested (glucose, protein, fat, or placebo), and Difficulty Level (easy or hard). No effects of Nutrient were found in regard to overall task performance, collapsing across Age and Difficulty Level. There was no effect of Nutrient on the different performance levels of both age groups, or for the two task difficulty levels. However, post-hoc analyses did reveal a significant Nutrient x Age interaction for the elderly after ingestion of the protein drink. Trends in the data also pointed towards an enhancement effect of glucose for the paragraph recall and mental arithmetic tasks. Trends associated with performance levels after fat ingestion showed that fat tended to enhance mental arithmetic accuracy performance for the older adult age group. Protein did not appear to differ from placebo on any of the tasks, with the exception of the deficit in performance seen with the elderly on the mental arithmetic accuracy task. In addition, a post-hoc analysis of the effects of Nutrient on mood-state showed a significant Nutrient x Mood x Time interaction. These results were discussed in light of task-specific effects of nutrients and nutrient metabolism

Molecular Evolution and Functional Diversification of Replication Protein A1 in Plants

Replication protein A (RPA) is a heterotrimeric, single-stranded DNA binding complex required for eukaryotic DNA replication, repair, and recombination. RPA is composed of three subunits, RPA1, RPA2, and RPA3. In contrast to single RPA subunit genes generally found in animals and yeast, plants encode multiple paralogs of RPA subunits, suggesting subfunctionalization. Genetic analysis demonstrates that five Arabidopsis thaliana RPA1 paralogs (RPA1A to RPA1E) have unique and overlapping functions in DNA replication, repair, and meiosis. We hypothesize here that RPA1 subfunctionalities will be reflected in major structural and sequence differences among the paralogs. To address this, we analyzed amino acid and nucleotide sequences of RPA1 paralogs from 25 complete genomes representing a wide spectrum of plants and unicellular green algae. We find here that the plant RPA1 gene family is divided into three general groups termed RPA1A, RPA1B, and RPA1C, which likely arose from two progenitor groups in unicellular green algae. In the family Brassicaceae the RPA1B and RPA1C groups have further expanded to include two unique sub-functional paralogs RPA1D and RPA1E, respectively. In addition, RPA1 groups have unique domains, motifs, cis-elements, gene expression profiles, and pattern of conservation that are consistent with proposed functions in monocot and dicot species, including a novel C-terminal zinc-finger domain found only in plant RPA1C-like sequences. These results allow for improved prediction of RPA1 subunit functions in newly sequenced plant genomes, and potentially provide a unique molecular tool to improve classification of Brassicaceae species

Genetic analysis of the Replication Protein A large subunit family in Arabidopsis reveals unique and overlapping roles in DNA repair, meiosis and DNA replication

Replication Protein A (RPA) is a heterotrimeric protein complex that binds single-stranded DNA. In plants, multiple genes encode the three RPA subunits (RPA1, RPA2 and RPA3), including five RPA1-like genes in Arabidopsis. Phylogenetic analysis suggests two distinct groups composed of RPA1A, RPA1C, RPA1E (ACE group) and RPA1B, RPA1D (BD group). ACE-group members are transcriptionally induced by ionizing radiation, while BD-group members show higher basal transcription and are not induced by ionizing radiation. Analysis of rpa1 T-DNA insertion mutants demonstrates that although each mutant line is likely null, all mutant lines are viable and display normal vegetative growth. The rpa1c and rpa1e single mutants however display hypersensitivity to ionizing radiation, and combination of rpa1c and rpa1e results in additive hypersensitivity to a variety of DNA damaging agents. Combination of the partially sterile rpa1a with rpa1c results in complete sterility, incomplete synapsis and meiotic chromosome fragmentation, suggesting an early role for RPA1C in promoting homologous recombination. Combination of either rpa1c and/or rpa1e with atr revealed additive hypersensitivity phenotypes consistent with each functioning in unique repair pathways. In contrast, rpa1b rpa1d double mutant plants display slow growth and developmental defects under non-damaging conditions. We show these defects in the rpa1b rpa1d mutant are likely the result of defective DNA replication leading to reduction in cell division

Once Upon an Assessment

For this research Six-Piece Story Making, an assessment created by Mooi Lahad (2006), was used to elicit a more creative way of assessing risk daily with children. After reviewing the literature on the topic of using storytelling as a therapeutic intervention with children, it was found that there is a lack of information around using storytelling within a partial hospitalization environment. This research began to explore the possibilities of using storytelling in a partial hospitalization setting with male and female children aging in range from 6 to 13 years of age. It was found that within a partial hospitalization program using storytelling at the start of the program fostered within the clients the ability to create playful environment that fostered an openness with the children during the risk assessment questions. Another finding was that the participants showed more agency and ownership when creating a treatment goal to focus on during that day of treatment. This was an unexpected benefit that was documented through the research and was evidence to the fact that by implementing Six-Piece Story Making at the partial hospitalization program risk can be assessed in a creative and playful way that encourages the child’s involvement in their treatment goals

Student and Teacher Perceptions of First Language Use in Secondary French Immersion Mathematics Classrooms

This phenomenological study (Creswell, 2003, 2007; van Manen, 1997) explores student and teacher perceptions of first language use in French immersion mathematics classrooms at a large, urban high school in Canada. During individual interviews, participants discussed their perceptions and experiences of French immersion mathematics, language use, and, in particular, first language use. Interview data are analysed through a sociocultural theory lens (e.g., Lantolf, 2000; Swain & Lapkin, 2000), drawing on key notions such as language interdependence and the use of language as a cognitive tool. While first language use in second language classrooms remains controversial, this article contributes to an open discussion on the potential role students’ first language can play in determining effective language and content learning.Cette étude phénoménologique (Creswell, 2003, 2007; van Manen, 1997) porte sur les perceptions des élèves et des enseignants sur l’emploi de la langue première pendant les cours de mathématiques dans un contexte d’immersion française d’une grande école secondaire en milieu urbain au Canada. Pendant les entrevues individuelles, les participants ont discuté de leurs perceptions et leurs expériences relatives aux cours de mathématiques en immersion et à l’emploi de langue, notamment la langue première. Les données d’entrevues ont été analysées dans l’optique de la théorie socioculturelle (p.ex., Lantolf, 2000; Swain & Lapkin, 2000), puisant dans des notions clés telles l’interdépendance des langues et l’emploi de langue comme outil cognitif. Alors que l’emploi de la première langue dans les classes d’immersion est controversé, cet article contribue à une discussion ouverte sur le rôle potentiel que peut jouer la langue première des élèves dans la détermination de l’apprentissage efficace de la langue et du contenu