301 research outputs found

    Effective teaching

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    In this paper I intend to support the hypothetical statement attributed to Socrates in Murray\u27s (1994) article, namely that \u27Excellent teaching is that which produces learning and understanding.\u27 If I am wrong in what I say it is your business to take up the argument and refute me

    The new learning market

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    Agricultural shows: visitor motivation, experience and behavioural intention

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    Purpose - This paper contributes to theory concerning visitor motivations, consumer experience and behavioural intentions at rural events; more specifically, it focuses on agricultural shows, which have hitherto been neglected in the events management literature. These events have successfully broadened their visitor base, but not without the attendant challenges for agricultural events' designers. Design/methodology/approach - The research adopts a quantitative design using a questionnaire survey. The analysis, using a range of statistical procedures, centres on consumer motivation, experience and behaviour in relation to show features and their influence on future behaviour. Findings - Demonstrate the relative importance to the consumer, of the show’s various components and their influence on revisitation, which reflect the significance of social, cultural and personal meanings attached to their experiences. This highlights key motivational variables such as appreciating the shows' traditions and intellectual enrichment Research limitations/implications - The study takes a cross sectional approach, using a non-probability sample at four multiday royal shows. Future research should establish the external validity of the findings and their applicability to smaller one day agricultural shows Practical implications - The research provides a managerial contribution by informing show designers about the motivations of an increasingly diverse range of visitors. This will facilitate decisions around the engagement of contemporary design while preserving the traditional elements of agricultural shows. Originality/value - Few studies have looked at rural events and, in particular, agricultural shows. Moreover, previous research in this area has focused on rural tourism and place making, while consumer behaviour and experience at rural events has been neglected. This paper provides an insight into the consumer experience and perceived importance of various aspects of contemporary agricultural shows

    The influence of organizational subcultures in health organizations

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    This study investigates the mediating role of organizational subculture and its antecedents of organizational commitment namely leadership, culture and job satisfaction. Structural equation analysis is used to examine our model in which organizational subculture mediated the influence of leadership style and organizational culture on commitment, and in which job satisfaction is an antecedent of commitment. The results of this study highlight the important role of local leadership and subculture in determining employees’ job satisfaction and commitment. The findings in this study could also provide managers with a new lens to examine organizational culture via three perspectives: bureaucratic, supportive and innovative. Furthermore, the results could renew interests in developing other organizational subculture models that could determine the relationship between organizational subculture and commitmen

    Pre-treatment of lignocellulosic feedstocks using biorenewable alcohols::towards complete biomass valorisation

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    Here, we report on the ability of the biomass derived solvents ethanol and, in particular, n-butanol to fractionate lignocellulose into its main components. An organosolv system consisting of n-butanol containing 5% water and 0.2 M HCl at reflux was found to remove effectively the lignin and hemicellulose components of lignocellulosic biomass leaving a cellulose pulp suitable for enzymatic hydrolysis to simple sugars. Using a hardwood beech pulp as an example, essentially complete conversion of the cellulose component to reducing sugars was achieved with a cellulase loading of 22 FPU per g. Analysis of the solubilised hemicellulose fractions revealed that they consist almost exclusively of alkyl xylosides and mannosides which could serve as valuable synthetic building blocks. Additionally, the mild conditions (<120 °C) and high alcohol content of the pre-treatment solvent suppressed lignin degradation reactions and allowed for the isolation of high quality lignins in good yields. Detailed HSQC NMR analysis of the isolated lignins revealed that they still contained large amounts of β-aryl ether units, especially α-ethoxylated and α-butoxylated β-O-4 units, making them particularly suitable for depolymerisation to mono-aromatic chemicals. This was demonstrated using a recently reported acidolysis method utilizing ethylene glycol which gave monomer yields of between 7.4 and 18 wt%. The yields for n-butanol lignins were at least four fold higher than those obtained from a current generation technical organosolv lignin under comparable conditions

    Characterisation of Osteopontin in an In Vitro Model of Embryo Implantation

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    At the onset of pregnancy, embryo implantation is initiated by interactions between the endometrial epithelium and the outer trophectoderm cells of the blastocyst. Osteopontin (OPN) is expressed in the endometrium and is implicated in attachment and signalling roles at the embryo–epithelium interface. We have characterised OPN in the human endometrial epithelial Ishikawa cell line using three different monoclonal antibodies, revealing at least nine distinct molecular weight forms and a novel secretory pathway localisation in the apical domain induced by cell organisation into a confluent epithelial layer. Mouse blastocysts co-cultured with Ishikawa cell layers served to model embryo apposition, attachment and initial invasion at implantation. Exogenous OPN attenuated initial, weak embryo attachment to Ishikawa cells but did not affect the attainment of stable attachment. Notably, exogenous OPN inhibited embryonic invasion of the underlying cell layer, and this corresponded with altered expression of transcription factors associated with differentiation from trophectoderm (Gata2) to invasive trophoblast giant cells (Hand1). These data demonstrate the complexity of endometrial OPN forms and suggest that OPN regulates embryonic invasion at implantation by signalling to the trophectoder

    Osmotic stress induces JNK-dependent embryo invasion in a model of implantation

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    In vitro culture during assisted reproduction technologies (ARTs) exposes pre-implantation embryos to environmental stressors, such as non-physiological nutritional, oxidative and osmotic conditions. The effects on subsequent implantation are not well understood but could contribute to poor ART efficiency and outcomes. We have used exposure to hyperosmolarity to investigate the effects of stress on the ability of embryos to interact with endometrial cells in an in vitro model. Culturing mouse blastocysts for 2 h in medium with osmolarity raised by 400 mosmol induced blastocoel collapse and re-expansion, but did not affect subsequent attachment to, or invasion of, the endometrial epithelial Ishikawa cell line. Inhibition of stress-responsive c-Jun N-terminal kinase (JNK) activity with SP600125 did not affect the intercellular interactions between these embryos and the epithelial cells. Four successive cycles of hyperosmotic stress at E5.5 had no effect on attachment, but promoted embryonic breaching of the epithelial cell layer by trophoblast giant cells in a JNK-dependent manner. These findings suggest that acute stress at the blastocyst stage may promote trophoblast breaching of the endometrial epithelium at implantation and implicates stress signalling through JNK in the process of trophectoderm differentiation into the invasive trophoblast necessary for the establishment of pregnancy. The data may lead to increased understanding of factors governing ART success rates and safety

    Metal triflates for the production of aromatics from lignin

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    This work was funded by the European Union (Marie Curie ITN ‘SuBiCat’ PITN-GA-2013-607044, PJD, CWL, NJW, PCKL, KB, JGdeV) as well as EP/J018139/1, EP/K00445X/1 grants (NJW and PCJK) and an EPSRC Doctoral Prize Fellowship (CSL).The depolymerization of lignin into valuable aromatic chemicals is one of the key goals towards establishing economically viable biorefineries. In this contribution we present a simple approach for converting lignin to aromatic monomers in high yields, under mild reaction conditions. The methodology relies on the use of catalytic amounts of easy to handle metal triflates (M(OTf)x). Initially, we evaluated the reactivity of a broad range of metal triflates using simple lignin model compounds. More advanced lignin model compounds were also used to study the reactivity of different lignin linkages. The product aromatic monomers were either phenolic C2-acetals obtained by stabilization of the aldehyde cleavage products by reaction with ethylene glycol, or methyl aromatics obtained by catalytic decarbonylation. Notably, when the former method was ultimately tested on lignin, especially Fe(OTf)3 proved very effective and the phenolic C2-acetal products were obtained in an excellent, 19.3±3.2 wt % yield.PostprintPeer reviewe

    Apposition to endometrial epithelial cells activates mouse blastocysts for implantation.

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    How do interactions between blastocyst-stage embryos and endometrial epithelial cells regulate the early stages of implantation in an in vitro model?Mouse blastocyst apposition with human endometrial epithelial cells initiates trophectoderm differentiation to trophoblast, which goes on to breach the endometrial epithelium.In vitro models using mouse blastocysts and human endometrial cell lines have proven invaluable in the molecular characterisation of embryo attachment to endometrial epithelium at the onset of implantation. Genes involved in embryonic breaching of the endometrial epithelium have not been investigated in such in vitro models.This study used an established in vitro model of implantation to examine cellular and molecular interactions during blastocyst attachment to endometrial epithelial cells.Mouse blastocysts developed from embryonic day (E) 1.5 in vitro were hatched and co-cultured with confluent human endometrial adenocarcinoma-derived Ishikawa cells in serum-free medium. A scale of attachment stability based on blastocyst oscillation upon agitation was devised. Blastocysts were monitored for 48 h to establish the kinetics of implantation, and optical sectioning using fluorescence microscopy revealed attachment and invasion interfaces. Quantitative PCR was used to determine blastocyst gene expression. Data from a total of 680 mouse blastocysts are reported, with 3-6 experimental replicates. T-test and ANOVA analyses established statistical significance at P < 0.05, P < 0.01 and P < 0.001.Hatched E4.5 mouse blastocysts exhibited weak attachment to confluent Ishikawa cells over the first 24 h of co-culture, with intermediate and stable attachment occurring from 28 h (E5.5 + 4 h) in a hormone-independent manner. Attached embryos fixed after 48 h (E6.5) frequently exhibited outgrowths, characterised morphologically and with antibody markers as trophoblast giant cells (TGCs), which had breached the Ishikawa cell layer. Beginning co-culture at E5.5 also resulted in intermediate and stable attachment from E5.5 + 4 h; however, these embryos did not go on to breach the Ishikawa cell layer, even when co-culture was extended to E7.5 (P < 0.01). Blastocysts cultured from E4.5 in permeable transwell inserts above Ishikawa cells before transfer to direct co-culture at E5.5 went on to attach but failed to breach the Ishikawa cell layer by E6.5 (P < 0.01). Gene expression analysis at E5.5 demonstrated that direct co-culture with Ishikawa cells from E4.5 resulted in downregulation of trophectoderm transcription factors Cdx2 (P < 0.05) and Gata3 (P < 0.05) and upregulation of the TGC transcription factor Hand1 (P < 0.05). Co-culture with non-endometrial human fibroblasts did not alter the expression of these genes.None.The in vitro model used here combines human carcinoma-derived endometrial cells with mouse embryos, in which the cellular interactions observed may not fully recapitulate those in vivo. The data gleaned from such models can be regarded as hypothesis-generating, and research is now needed to develop more sophisticated models of human implantation combining multiple primary endometrial cell types with surrogate and real human embryos.This study implicates blastocyst apposition to endometrial epithelial cells as a critical step in trophoblast differentiation required for implantation. Understanding this maternal regulation of the embryonic developmental programme may lead to novel treatments for infertility.This work was supported by funds from the charities Wellbeing of Women (RG1442) and Diabetes UK (15/0005207), and studentship support for SCB from the Anatomical Society. No conflict of interest is declared
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