420 research outputs found

    Joining the dots through Scottish crofting education

    Get PDF
    The ‘Crofting Connections’ (Ceanglaichean Croitearachd) project is described in this article as an exemplar of the prescribed ‘Scottish approach’ to Education for Sustainable Development (ESD). Drawing upon the evaluation of this project an argument is made for increased attention to such initiatives that seek to (re)connect children with issues of community, heritage, land and place. In doing so, we also call for a reconceptualization of crofting in academic discourse and in the curriculum. While crofting is a specifically Scottish phenomenon, this may be of interest to readers in other nations with similar small scale agricultural traditions

    microRNAs of parasitic helminths – identification, characterization and potential as drug targets

    Get PDF
    microRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional gene regulation. They were first identified in the free-living nematode Caenorhabditis elegans, where the miRNAs lin-4 and let-7 were shown to be essential for regulating correct developmental progression. The sequence of let-7 was subsequently found to be conserved in higher organisms and changes in expression of let-7, as well as other miRNAs, are associated with certain cancers, indicating important regulatory roles. Some miRNAs have been shown to have essential functions, but the roles of many are currently unknown. With the increasing availability of genome sequence data, miRNAs have now been identified from a number of parasitic helminths, by deep sequencing of small RNA libraries and bioinformatic approaches. While some miRNAs are widely conserved in a range of organisms, others are helminth-specific and many are novel to each species. Here we review the potential roles of miRNAs in regulating helminth development, in interacting with the host environment and in development of drug resistance. Use of fluorescently-labeled small RNAs demonstrates uptake by parasites, at least in vitro. Therefore delivery of miRNA inhibitors or mimics has potential to alter miRNA activity, providing a useful tool for probing the roles of miRNAs and suggesting novel routes to therapeutics for parasite control

    Of myths and monitoring: learner-centred education as a political project in Scotland

    Get PDF
    Prevalent constructions of best practice at the global level include learner-centred education as an emancipatory and holistic approach across the life course. However, competing discourses of standardisation and preparation for the workforce are also at play. As a small state constructing an image and role for itself on a global stage, Scotland draws aspirationally on learner-centredness in its current Curriculum for Excellence governing education in schools, and in the Statement of Ambition for Adult Education, aligning it with apparently indigenous ideas of good practice in education while distancing it from prevalent patterns in neighbouring England. However, in operationalising these, competing agendas and versions of best practice interrupt these policy narratives and prove difficult to resist. Using a combination of document analysis, observations of consultation processes, and interviews with policy actors, this article explores these tensions in policy content and process

    Application of small RNA technology for improved control of parasitic helminths

    Get PDF
    Over the last decade microRNAs (miRNAs) and small interfering RNAs (siRNAs) have emerged as important regulators of post-transcriptional gene expression. miRNAs are short, non-coding RNAs that regulate a variety of processes including cancer, organ development and immune function. This class of small RNAs bind with partial complementarity to their target mRNA sequences, most often in the 3′UTR, to negatively regulate gene expression. In parasitic helminths, miRNAs are being increasingly studied for their potential roles in development and host-parasite interactions. The availability of genome data, combined with small RNA sequencing, has paved the way to profile miRNAs expressed at particular developmental stages for many parasitic helminths. While some miRNAs are conserved across species, others appear to be unique to specific parasites, suggesting important roles in adaptation and survival in the host environment. Some miRNAs are released from parasites, in exosomes or in protein complexes, and the potential effects of these on host immune function are being increasingly studied. In addition, release of miRNAs from schistosome and filarial parasites into host plasma can be exploited for the development of specific and sensitive diagnostic biomarkers of infection. Interfering with miRNA function, as well as silencing key components of the pathways they regulate, will progress our understanding of parasite development and provide a novel approach to therapeutic control. RNA interference (RNAi) by siRNAs has proven to be inconsistent in parasitic nematodes. However, the recent successes reported for schistosome and liver fluke RNAi, encourage further efforts to enhance delivery of RNA and improve in vitro culture systems and assays to monitor phenotypic effects in nematodes. These improvements are important for the establishment of reliable functional genomic platforms for novel drug and vaccine development. In this review we focus on the important roles of miRNAs and siRNAs in post-transcriptional gene regulation in veterinary parasitic helminths and the potential value of these in parasite diagnosis and control

    The genealogy and governance of ‘A Curriculum for Excellence’. A case study in educational policymaking in post-devolution Scotland

    Get PDF
    This dissertation has been submitted in fulfilment of the requirements of the University of Glasgow EdD. As someone with a professional background in education, government and parliament, and an academic background in politics and citizenship, I was keen to identify an area of study that might draw upon these areas of interest. The emergence of A Curriculum for Excellence as a major new policy initiative in the mid-2000s appeared to represent an ideal case study scenario for just such a study. I wished to examine the ways in which this policy had been initiated, formulated, developed and implemented. In particular I was very aware of the optimistic and aspirational claims around new and improved modes of policymaking that had contributed to the discourse around devolution in the late 1990s. I wanted to test these claims in the light of the development of A Curriculum for Excellence. In order to address these claims I developed a conceptual framework that placed a strong emphasis on themes of genealogy and governance. Through this framework, and a methodology based on literature review and in depth interviews with some key participants in the policy process, I hoped to scrutinise some aspects of the Scottish policy process that are rarely examined. These include the influential role of individuals and organisations, the ways in which policy is mediated in an apparent pursuit of consensus and the consequences of this approach to policy. My core research questions were: 1. To what extent was the genealogy of A Curriculum for Excellence influenced and shaped by the post-devolutionary context? 2. Does an analysis of the governance of A Curriculum for Excellence provide evidence of a change in post-devolution policymaking in education? 3. What does the educational policymaking architecture look like in post-devolution Scotland? In answering these questions I identified a number of key findings, including that the Curriculum for Excellence (CfE) development can be situated in a policy context that has been informed by the advent of devolution. It provides partial evidence of a change in the post devolution conduct of education policy, although some procedures for policy consultation should be reviewed and enhanced further, with a greater focus on deliberative forms of engagement at all stages in the policy process. Policy goals should be stated more clearly and in ways that can facilitate review and evaluation. Procedures should also be put in place to promote greater continuity of staff and institutions involved in the core development and delivery of major policy initiatives in Scottish education. The policy architecture that has emerged in the post-devolution period is a hybrid model that has not resolved the longstanding tension between consensual, pluralistic and mediating instincts on the one hand; and centralised control and governance on the other. The informal and organic system of checks and balances in the Scottish policy landscape that had evolved in the pre-devolutionary era has to a large extent been retained. This has implications for the scope, speed and ambition of any policy development and implementation, as exemplified by CfE in this case study. In order to improve the prospects for effective policy change in future, I recommend that the roles of the different organisations with responsibility for educational policymaking in Scotland should be reviewed and clarified. Furthermore the procedures for policymaking should be clarified, formalised and made more transparent in the same way as legislative procedures were reviewed as part of the devolution settlement

    Conservation of a microRNA cluster in parasitic nematodes and profiling of miRNAs in excretory-secretory products and microvesicles of Haemonchus contortus

    Get PDF
    microRNAs are small non-coding RNAs that are important regulators of gene expression in a range of animals, including nematodes. We have analysed a cluster of four miRNAs from the pathogenic nematode species Haemonchus contortus that are closely linked in the genome. We find that the cluster is conserved only in clade V parasitic nematodes and in some ascarids, but not in other clade III species nor in clade V free-living nematodes. Members of the cluster are present in parasite excretory-secretory products and can be detected in the abomasum and draining lymph nodes of infected sheep, indicating their release in vitro and in vivo. As observed for other parasitic nematodes, H. contortus adult worms release extracellular vesicles (EV). Small RNA libraries were prepared from vesicle-enriched and vesicle-depleted supernatants from both adult worms and L4 stage larvae. Comparison of the miRNA species in the different fractions indicated that specific miRNAs are packaged within vesicles, while others are more abundant in vesicle-depleted supernatant. Hierarchical clustering analysis indicated that the gut is the likely source of vesicle-associated miRNAs in the L4 stage, but not in the adult worm. These findings add to the growing body of work demonstrating that miRNAs released from parasitic helminths may play an important role in host-parasite interactions

    Nano-scale behavior of irradiated nano-structured alloys

    Get PDF
    Future fast neutron fusion and fission nuclear systems will be subjected to levels of radiation damage from fast neutrons which is significantly higher than the current generation of nuclear power stations. This will require innovative materials solutions to allow long term mechanical stability of reactors. One proposed class of materials are nanostructured alloys where the large number of interfaces allow for recombination defects and reduce the degree of radiation hardening seen. However their response under irradiation has not thoroughly been studied. In this work, two irradiated nanostructured alloys have been studied W-5%Re in both a nanostructured and annealed variant and a novel Hf-Ti-Ta-V-Zr high entropy alloy. I will outline the benefits nanostructured materials offer under irradiation and some of the problems and challenges in measuring their mechanical properties after irradiation and relating this to the nano-structure using XRD, TEM, HR-EBSD and atom probe tomography. Rolled tungsten 5 wt% rhenium sheet was studied in two microstructural variants: (a) as received with a high dislocation density (mean value of 1.4×1014lines/m2), measured using HR-EBSD, and pancake shaped grains with a thickness of≈200nm and (b) annealed at 1400oC for 24 hours to produce equiaxed grains with average grain size of ≈90 µm and low dislocation density (with a mean value of 4.8×1013 lines/m2). Both materials were ion implanted with 2MeV W+ ions at 300oC to damage levels from 0.07, to 33 displacements per atom (dpa). Nanoindentation was used to measure the change in hardness after implantations. Irradiation induced hardening saturated in the as-received material at an increase of 0.4dpa from the unimplanted hardness of 8GPa at 0.4dpa. In the annealed material saturation does not occur by 13dpa and the hardness change of 1.3GPa from the unimplanted hardness of 6.2GPa was over four times higher. At 33dpa both material types showed a further increase in hardening. In these samples Atom probe tomography showed clustering of Re in ≈4nm precipitates with a rhenium concentration of ≈11%. In both cases the number density and volume fraction are similar at ≈3100 x1000/µm3 and volume fraction of ≈13%. These differences in radiation response are likely to be due to the high damage sink density in the as-received microstructure in the form of dislocation networks, as even in the as-received material the average grain size is too large to provide sufficient sinks. Initially this provides a large sink network for radiation damage resulting in less hardening in the rolled material. However at 33dpa the formation of rhenium clusters occurs at similar levels in both material conditions. These dominate the hardening mechanisms and result in secondary hardening at high damage levels. The difficulties in extracting hardness values from 200nm deep ion implanted layers will be discussed, with reference to minimizing the influence of the substrate material and how changes in pile up effects in irradiated materials can change mechanical responses, and proposed methods to minimize these. High entropy alloys have been proposed as potential nuclear materials as high configurational entropy may provide resistance to radiation damage. We have produced a novel high entropy alloy (Hf-Ti-Ta-V-Zr) in which is single phase on casting but two high entropy phases (one bcc and one hcp) are produced during heat treatment. This material then has a nano-lamella structure with an average lamella thickness of 200nm. Samples of the as cast single phase material, the dual phase high entropy alloy and single crystal vanadium were ion irradiated with V+ ions at 300oC to a dose of 5e14 ions/cm2. In the vanadium control samples the hardness as measured using CSM-nanoindentation was seen to increase from 2GPa in the unimplanted condition to 3.5GPa in the ion irradiated condition. The high entropy alloy in both the as cast and heat treated condition showed no increase in hardness after irradiation, demonstrating the intrinsic resistance to radiation damage of HEA’s. These studies show the ability of nanostructured alloys to have improved irradiation hardening resistance over conventional alloys. However challenges still remain in the production of large scale engineering components in such materials

    Association between socioeconomic status, sex, and age at death from cystic fibrosis in England and Wales (1959 to 2008): cross sectional study

    Get PDF
    Objective To determine the trend in the association between socioeconomic status and sex and median age at death from cystic fibrosis in England and Wales, over the past 50 years

    Increased expression of a microRNA correlates with anthelmintic resistance in parasitic nematodes

    Get PDF
    Resistance to anthelmintic drugs is a major problem in the global fight against parasitic nematodes infecting humans and animals. While previous studies have identified mutations in drug target genes in resistant parasites, changes in the expression levels of both targets and transporters have also been reported. The mechanisms underlying these changes in gene expression are unresolved. Here, we take a novel approach to this problem by investigating the role of small regulatory RNAs in drug resistant strains of the important parasite Haemonchus contortus. microRNAs (miRNAs) are small (22 nt) non-coding RNAs that regulate gene expression by binding predominantly to the 3′ UTR of mRNAs. Changes in miRNA expression have been implicated in drug resistance in a variety of tumor cells. In this study, we focused on two geographically distinct ivermectin resistant strains of H. contortus and two lines generated by multiple rounds of backcrossing between susceptible and resistant parents, with ivermectin selection. All four resistant strains showed significantly increased expression of a single miRNA, hco-miR-9551, compared to the susceptible strain. This same miRNA is also upregulated in a multi-drug-resistant strain of the related nematode Teladorsagia circumcincta. hco-miR-9551 is enriched in female worms, is likely to be located on the X chromosome and is restricted to clade V parasitic nematodes. Genes containing predicted binding sites for hco-miR-9551 were identified computationally and refined based on differential expression in a transcriptomic dataset prepared from the same drug resistant and susceptible strains. This analysis identified three putative target mRNAs, one of which, a CHAC domain containing protein, is located in a region of the H. contortus genome introgressed from the resistant parent. hco-miR-9551 was shown to interact with the 3′ UTR of this gene by dual luciferase assay. This study is the first to suggest a role for miRNAs and the genes they regulate in drug resistant parasitic nematodes. miR-9551 also has potential as a biomarker of resistance in different nematode species

    Identity Foreclosure, Athletic Identity, and College Sport Participation

    Get PDF
    A study was conducted with 502 college students (246 non-athletes, 90 intramural athletes, and 166 intercollegiate athletes) to investigate the relationship between self-identity variables (i.e., identity foreclosure and athletic identity) and college sport participation. The researchers used two scales, the foreclosure subscale of the Objective Measure of Ego Identity Status (OM-EIS, Adams et al., 1979) and the Athletic Identity Measurement Scale (AIMS, Brewer et al., 1993). Results indicated that identity foreclosure and athletic identity increase with level of sport participation. Identity foreclosure was significantly lower for upperclass students than for underclass students among non-athletes, but not among intramural and intercollegiate student-athletes. No gender differences were found. These findings suggested that intercollegiate student-athletes may commit to the role of "athlete" without exploring alternative identities. Implications of the results for the academic and career development of student-athletes were discussed. "The results of this study imply that college student-athletes may identify strongly with the athlete role to the extent that they fail to explore alternative identities." - p.
    • …
    corecore