336 research outputs found

    Asymmetries of knowledge between children and teachers on a New Zealand bush walk

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    Abstract This article presents the analysis of a single case interaction between two preschool children aged four-years-old and their male early childhood teacher during a routine excursion to the New Zealand bush. The findings build on prior research that revealed how child-initiated enquiries orienting to an environmental feature in the outdoor space provoked an affiliated interaction with the teacher, or not. The current article suggests that, although early childhood education promotes a socio-cultural co-construction of knowledge, asymmetries of knowledge are often present in everyday practice. A call to investigate the interactional features of co-construction and scaffolding is recommended

    Structure, Synthesis and Biological Activity of Harmful Algal Bloom Toxins from Karlodinium sp. and Exploration of Microbial Derived Natural Products

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    This work features natural products isolated from both the marine and microbial environments. Part I focuses on the elucidation of toxins from harmful algal blooms (HAB). The HAB dinoflagellate Karlodinium veneficum produces a harmful suite of molecules identified as the karlotoxins (KmTx) that have been implicated in massive fish kills pan-globally. Nine new karlotoxin congeners were isolated from various Karlodinium blooms around the world and utilizing the structure of KmTx2 were characterized using overlaid 2D NMR techniques. Due to the contrasting conformational differences between KmTx and the closely related amphidinols, the absolute configuration of KmTx was further evaluated by extensive computational analysis of the J-based coupling constants (JBCA) and chemical shifts (CS) of the 1H and 13C NMR data. In addition, the total synthesis of one congener is being attempted to obtain additional material for biological studies and further structure activity relationship (SAR) studies. The expanded SAR of the class is being explored for new insights for agents for the treatment of cancer and as angiogenesis inhibitors. Part II focuses on the isolation and characterization of novel lactone lipids, scoriosin and its methyl ester, isolated from Scorias spongiosa, a fungus that is commonly referred to as sooty mold and can be found growing on both Fagus sylvaticus and Fagus grandifolia, better known as the European and American beech trees. Using a combination of calculated and experimental electronic circular dichroism (ECD) and CS analysis, the absolute configuration of the molecules was established. Both compounds displayed antimicrobial and antifungal activity with IC50 values in the low µM to high nM range for Cryptococcus neoformans, Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). The second project in Part II focuses on using matrix assisted laser desorption ionization- mass spectrometry (MALDI-MS) imaging to confirm production of key pharmaceutical precursor secondary metabolites from marine associated bacteria. Through microbial community analysis, optimization of fermentation conditions and MALDI-MS imaging, the first report of a sponge-associated bacterium (Micromonospora sp. M42) from the Indo-Pacific sponge Acanthostrongylophora ingens (Thiele, 1899) that produces the manzamine class of antimalarials is presented

    Risk-taking in the New Zealand Bush: issues of resilience and wellbeing

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    This article discusses a single case analysis of teacher-child interactions on an everyday bush walk in New Zealand. It uses a combination of the Leuven wellbeing scale (Laevers, 2000) and a conversation analysis approach to explore how children and teachers attend to specific features of the outdoor environment in a way that encourages risk-taking and builds resilience through problem solving. The collaborative achievement of the activities between the pre- school teacher and the fouryear-old children are discussed as an important and necessary aspect of the interactions, which we suggest may represent physical sustained shared thinking, for supporting wellbeing whilst building resilience and risk-taking. Implications for future practice are considered with regard to implementation of early childhood curricula

    Monanchocidin A From Subarctic Sponges of the Genus Monanchora and Their Promising Selectivity Against Melanoma in vitro

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    © Copyright © 2020 Gogineni, Oh, Waters, Kelly, Stone and Hamann. Marine sources have long been known for their potential to produce unique skeletons and various biological activities. Fractionation of the ethanol extracts of an undescribed species of Monanchora Carter, 1883 and a specimen closely comparable to Monanchora pulchra (Lambe, 1894/1895) (Class Demospongiae, Order Poecilosclerida, Family Crambeidae), yielded a known compound, monanchocidin A. Monanchocidin A, a secondary metabolite, showed very modest antibacterial, antifungal, and antiprotozoal activities with IC50 values ranging between 255.75 and 7288.92 μM. Monanchocidin A also exhibited potent selective activity for the melanoma panel in the NCI cancer cell screening panel

    Effect of suckler cow vaccination against glycoprotein E (gE)-negative bovine herpesvirus type 1 (BoHV-1) on passive immunity and physiological response to subsequent bovine respiratory disease vaccination of their progeny

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    peer-reviewedThe study objectives were: 1) to characterise the development of immunocompetence in beef suckler calves from birth to three months of age, and 2) to trace glycoprotein E (gE)-negative bovine herpesvirus type 1 (BoHV-1) antibodies from dam to calf and subsequent vaccination against pneumonia. Thirty multiparous beef suckler, spring-calving cows, consisting of two genotypes were involved; Limousin × Friesian (LF) and Charolais × Limousin (CL). Cows were immunised against the inactivated antigen strain of BoHV-1 (gE- (IBR marker vaccine) at day − 84 and received a booster at day − 56 relative to the expected calving date (d 0). Calves were immunised at 14 and 42 days of age against PI-3 virus, BRSV and Mannheimia (Pasteurella) haemolytica serotype A1 using a commercial vaccine administered subcutaneously. Additionally, calves were immunised against BoHV-1 at 42 days of age, using 1 dose of a live commercial vaccine administered intranasally. Blood samples were collected from all calves (n = 30) via jugular venipuncture at birth, prior to colostrum feeding (0 h), at 12 h (h), 24 h, 72 h and 168 h after the initial feeding of colostrum, and at d 7, 14, 28, 42, 56 and 84 post birth. The mean ratio of gE negative antibodies circulating in the blood of LF and CL dams pre-partum scored negative to gE ab (S/N ≥ 0.70). Antibody levels of BoHV-1 (wild type (wt)) peaked at 12 h post-birth in calves and declined thereafter, as the maternal antibodies decayed. There was no difference in BoHV-1 and BRSV antibody levels in calves post vaccination.This research was funded by the Irish Government under the National Development Plan 2007-2013, Department of Agriculture, Food and the Marine (DAFM) Research Stimulus Fund ((Grant number: 11/S/131) (B. Earley, Principal Investigator)). Katie Tiernan was in receipt of a post-graduate fellowship as part of 11/S/131

    Redesign of a WW Domain Peptide for Selective Recognition of Single-Stranded DNA

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    A β-sheet mini-protein based on the FBP11 WW1 domain sequence has been redesigned for the molecular recognition of ssDNA. A previous report showed that a β-hairpin peptide dimer, (WKWK)2, binds ssDNA with low micromolar affinity but with little selectivity over duplex DNA. This report extends those studies to a three-stranded β-sheet mini-protein designed to mimic the OB-fold. The new peptide binds ssDNA with low micromolar affinity and shows about 10-fold selectivity for ssDNA over duplex DNA. The redesigned peptide no longer binds its native ligand, the polyproline helix, confirming that the peptide has been redesigned for the function of binding ssDNA. Structural studies provide evidence that this peptide consists of a well structured β-hairpin made of Strands 2&3 with a less structured first strand that provides affinity for ssDNA but does not improve the stability of the full peptide. These studies provide insight into protein-DNA interactions as well as a novel example of protein-redesign

    Sentence Comprehension in Aphasia: Stability of Performance

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    This study investigated the stability of 42 aphasic patients’ performance in measures of sentence comprehension. Accuracy data from 11 sentences types in each of 5 tasks were analyzed. Split-half reliability was generally high, and correlations for identical sentence types across tasks were slightly higher than those for different sentences across tasks. Analysis of individual patient data revealed only one patient with the same syntactic deficit on two tasks, and it may have been a speed/accuracy trade-off. These data suggest that performance on all sentence types combined is stable across tasks, but that task effects do influence performance

    Factors Underlying Sentence Comprehension in Older Adults and Patients with Aphasia

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    This study examined the factors that determine performance on measures of sentence comprehension. The participants were 42 people with aphasia and 25 non-brain damaged controls. There were two measures of performance: accuracy data from each of 5 tasks (Object Manipulation and two versions each of sentence picture matching and grammaticality judgment) and reaction time data from 4 of the tasks (all but object manipulation). The results showed that a single factor accounted for most of the variance in the data. This result was observed both for accuracy and reaction time data, and in both groups of participants
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