212 research outputs found
Wild Country Hall: Children’s learning at a residential outdoor education centre.
This thesis is about learning at a residential outdoor education centre [pseudonym:- Wild County Hall]. It poses and answers three questions:
• How useful might discursive positioning be as a perspective on learning?
• What are the discourses at Wild Country Hall and how are they different to schooling discourses?
• How might neo-Liberal discursive practices, including performativity and current schooling orthodoxies have affected the pedagogic practices at this centre?
The review of literature provides an overview of the key literature on outdoor, adventure and experiential learning, considering these through the lenses of learning as acquisition, participation and transformation, before discussing the literature on the discursive positioning of identity. Literature on the discursive practices of outdoor centres is then considered in relation to literature on neo-Liberalism and performativity in schools.
The methodology is ethnographic. Participant observations were conducted over a period of five years whilst children were participating in both the organised adventure activities and the residential life of the centre. Searches of the centre’s documentary archives, and follow up interviews with 22 children (aged eight to 11) and three adults were used to add richness to the observational data, and especially to better understand reported participant gains. Analysis was undertaken by coding themes in the data using QSR NVivo N6.
The findings suggest that acquisitional and participatory perspectives on learning are not totally adequate for explaining the reported changes in outlook and behaviour of the children who took part in the research. These benefits may be more usefully conceptualised as discursively re-positioned identity. It is suggested that the perspective on learning as discursive positioning may be usefully employed by those studying residential outdoor education in the future. The findings show a number of over-arching discourses that dominate the life of Wild Country Hall. These include place - including the appreciation, care of and respect for nature, the sense of awe and wonder, understanding and protecting the environment – risk, challenge and adventure; and consequent confidence and resilience building by children through facing and over-coming their fears. Whilst some of these fears are linked to the adventure activities of the centre (such as fears of heights, water), other fears are associated with the residential nature of the centre; encountering and coping with homesickness, living with new people, encountering strange customs and unfamiliar social practices. So important were these unfamiliar discourses to the participating children that they may be looked upon as ‘rites of passage’. The findings suggest that encountering unfamiliar discourses may explain the efficacy of learning at Wild Country Hall.
Some of the pedagogic practices at Wild Country Hall were found to valorise what may be described as ‘classroom discourses’, and these have tended to formalise learning at the centre. It is suggested, therefore, that this outdoor centre has been influenced by performativity and classroom orthodoxy, themselves shaped by neo-Liberal agenda. These influences may be narrowing the range of discourses available and limiting the centre’s continuing ability to provide unfamiliar discourses, possibly to the detriment of children’s learning.
The conclusion makes a number of recommendations for policy practice and research. Recommendations for policy and practice focus on the narrowing tendencies observed at this centre, suggesting shifts in policy to retain the distinctiveness of outdoor education centres. Recommendations for research suggest that follow-up studies would be useful to test the findings in other outdoor centres and other areas of learning, whilst more methodological work could be done on memory and data research sites where contemporaneous notation and digital recording may be difficult or impossible
<i>Plasmodium </i>Condensin Core Subunits SMC2/SMC4 Mediate Atypical Mitosis and Are Essential for Parasite Proliferation and Transmission
Condensin is a multi-subunit protein complex regulating chromosome condensation and segregation during cell division. In Plasmodium spp., the causative agent of malaria, cell division is atypical and the role of condensin is unclear. Here we examine the role of SMC2 and SMC4, the core subunits of condensin, during endomitosis in schizogony and endoreduplication in male gametogenesis. During early schizogony, SMC2/SMC4 localize to a distinct focus, identified as the centromeres by NDC80 fluorescence and chromatin immunoprecipitation sequencing (ChIP-seq) analyses, but do not form condensin I or II complexes. In mature schizonts and during male gametogenesis, there is a diffuse SMC2/SMC4 distribution on chromosomes and in the nucleus, and both condensin I and condensin II complexes form at these stages. Knockdown of smc2 and smc4 gene expression reveals essential roles in parasite proliferation and transmission. The condensin core subunits (SMC2/SMC4) form different complexes and may have distinct functions at various stages of the parasite life cycle
Systematic analysis of Plasmodium myosins reveals differential expression, localisation, and function in invasive and proliferative parasite stages
The myosin superfamily comprises of actin‐dependent eukaryotic molecular motors important in a variety of cellular functions. Although well studied in many systems, knowledge of their functions in Plasmodium, the causative agent of malaria, is restricted. Previously, six myosins were identified in this genus, including three Class XIV myosins found only in Apicomplexa and some Ciliates. The well characterized MyoA is a Class XIV myosin essential for gliding motility and invasion. Here, we characterize all other Plasmodium myosins throughout the parasite life cycle and show that they have very diverse patterns of expression and cellular location. MyoB and MyoE, the other two Class XIV myosins, are expressed in all invasive stages, with apical and basal locations, respectively. Gene deletion revealed that MyoE is involved in sporozoite traversal, MyoF and MyoK are likely essential in the asexual blood stages, and MyoJ and MyoB are not essential. Both MyoB and its essential light chain (MCL‐B) are localised at the apical end of ookinetes but expressed at completely different time points. This work provides a better understanding of the role of actomyosin motors in Apicomplexan parasites, particularly in the motile and invasive stages of Plasmodium during sexual and asexual development within the mosquito
Plasmodium ARK2 and EB1 drive unconventional spindle dynamics, during chromosome segregation in sexual transmission stages
The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities by distinct protein scaffolds. Plasmodium spp., the causative agents of malaria, are unicellular eukaryotes with three unique and highly divergent aurora-related kinases (ARK1-3) that are essential for asexual cellular proliferation but lack most canonical scaffolds/activators. Here we investigate the role of ARK2 during sexual proliferation of the rodent malaria Plasmodium berghei, using a combination of super-resolution microscopy, mass spectrometry, and live-cell fluorescence imaging. We find that ARK2 is primarily located at spindle microtubules in the vicinity of kinetochores during both mitosis and meiosis. Interactomic and co-localisation studies reveal several putative ARK2-associated interactors including the microtubule-interacting protein EB1, together with MISFIT and Myosin-K, but no conserved eukaryotic scaffold proteins. Gene function studies indicate that ARK2 and EB1 are complementary in driving endomitotic division and thereby parasite transmission through the mosquito. This discovery underlines the flexibility of molecular networks to rewire and drive unconventional mechanisms of chromosome segregation in the malaria parasite.</p
A strongly magnetized pulsar within the grasp of the milky way’s supermassive black hole
The center of our Galaxy hosts a supermassive black hole, Sagittarius (Sgr) A∗. Young, massive stars within 0.5 pc of Sgr A∗ are evidence of an episode of intense star formation near the black hole a few million years ago, which might have left behind a young neutron star traveling deep into Sgr A∗’s gravitational potential. On 2013 April 25, a short X-ray burst was observed from the direction of the Galactic center. With a series of observations with the Chandra and the Swift satellites, we pinpoint the associated magnetar at an angular distance of 2.4±0.3 arcsec from Sgr A∗, and refine the source spin period and its derivative (P = 3.7635537(2) s and ˙ P = 6.61(4) × 10−12 s s−1), confirmed by quasi simultaneous radio observations performed with the Green Bank Telescope and Parkes Radio Telescope, which also constrain a dispersion measure of DM = 1750 ± 50 pc cm−3, the highest ever observed for a radio pulsar. We have found that this X-ray source is a young magnetar at ≈0.07–2 pc from Sgr A∗. Simulations of its possible motion around Sgr A∗ show that it is likely (∼90% probability) in a bound orbit around the black hole. The radiation front produced by the past activity from the magnetar passing through the molecular clouds surrounding the Galactic center region might be responsible for a large fraction of the light echoes observed in the Fe fluorescence features.We acknowledge support by grants AYA 2012-39303, SGR2009-811, iLINK 2011-0303, AYA 2010-21097-C03-02, Prometeo 2009/103, AYA2010-17631, P08-TIC-4075, INAF 2010 PRIN grant, Chandra Awards GO2-13076X, G03-14060X, GO3-14099X and G03-14121X, and an EU Marie Curie IEF (FP7-PEOPLE-2012-IEF-331095)
A Systematic Review of Immunological Studies of Erythema Nodosum Leprosum.
Erythema nodosum leprosum (ENL) is a painful inflammatory complication of leprosy occurring in 50% of lepromatous leprosy patients and 5-10% of borderline lepromatous patients. It is a significant cause of economic hardship, morbidity and mortality in leprosy patients. Our understanding of the causes of ENL is limited. We performed a systematic review of the published literature and critically evaluated the evidence for the role of neutrophils, immune complexes (ICs), T-cells, cytokines, and other immunological factors that could contribute to the development of ENL. Searches of the literature were performed in PubMed. Studies, independent of published date, using samples from patients with ENL were included. The search revealed more than 20,000 articles of which 146 eligible studies were included in this systematic review. The studies demonstrate that ENL may be associated with a neutrophilic infiltrate, but it is not clear whether it is an IC-mediated process or that the presence of ICs is an epiphenomenon. Increased levels of tumor necrosis factor-α and other pro-inflammatory cytokines support the role of this cytokine in the inflammatory phase of ENL but not necessarily the initiation. T-cell subsets appear to be important in ENL since multiple studies report an increased CD4+/CD8+ ratio in both skin and peripheral blood of patients with ENL. Microarray data have identified new molecules and whole pathophysiological pathways associated with ENL and provides new insights into the pathogenesis of ENL. Studies of ENL are often difficult to compare due to a lack of case definitions, treatment status, and timing of sampling as well as the use of different laboratory techniques. A standardized approach to some of these issues would be useful. ENL appears to be a complex interaction of various aspects of the immune system. Rigorous clinical descriptions of well-defined cohorts of patients and a systems biology approach using available technologies such as genomics, epigenomics, transcriptomics, and proteomics could yield greater understanding of the condition
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