173 research outputs found

    The effect of the amido substituent on polymer molecular weight in propene homopolymerisation by titanium cyclopentadienyl-amide catalysts

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    In the homopolymerisation of propene by the cyclopentadienyl-amide titanium catalyst systems [η5,η1-C5H4(CH2)2NR]TiCl2/MAO and [η5,η1-C5H4(CH2)2NR]Ti(CH2Ph)2/B(C6F5)3 (R = tBu, iPr, Me), the catalyst with the smallest substituent (Me) on the amido moiety consistently gives the highest polymer molecular weight. This differs from the trend usually observed in related catalysts with tetramethylcyclopentadienyl-amide ancillary ligands, where larger amide substituents result in higher molecular weights. Based on the present information a hypothesis is formulated in which an increased cation-anion interaction for the less sterically hindered catalyst is responsible for disfavouring chain transfer relative to chain growth.

    Downgraded curriculum? An analysis of knowledge in new curricula in Scotland and New Zealand

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    The development, since 2000, of new National Curricula across the Anglophone world signals a number of policy trends, including: a move from the explicit specification of content towards a more generic, skills-based approach; a greater emphasis on the centrality of the learner; and [ostensibly] greater autonomy for teachers in developing the curriculum in school. These policy shifts have attracted some criticism, especially from social realist writers, who claim that the new curricula downgrade knowledge. This paper offers a contribution to this debate; an empirically-based analysis of two new curricula, New Zealand’s Curriculum Framework and Scotland’s Curriculum for Excellence. We conclude that, while these curricula continue to accord considerable importance to knowledge in their statements of policy intent, the social realist critique is at least partially justified, since both curricula are characterised by a lack of coherence and mixed messages about the place of knowledge

    HIF1α-Dependent Induction of TFRC by a Combination of Intestinal Inflammation and Systemic Iron Deficiency in Inflammatory Bowel Disease

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    Background and Aims: Iron deficiency (ID) is a frequent extra-intestinal manifestation in patients with Inflammatory Bowel Disease (IBD), who often do not respond to iron supplementation. Iron is a cofactor for hydroxylases that suppress the hypoxia-inducible factor-1α (HIF1α), a transcription factor regulating iron homeostasis. We hypothesized that iron deficiency affects mucosal HIF1α activity in IBD. Methods: IBD patients (n = 101) were subdivided based on iron status (ferritin levels or transferrin saturation) and systemic inflammation (C-reactive protein levels). 154 corresponding ileal and colonic biopsies were analyzed for differential expression of 20 HIF1α pathway-associated genes and related to iron and inflammation status. In vitro expression of selected HIF1α pathway genes were analyzed in wild-type and HIF1A-null Caco-2 cells. Results: Gene expression of the mucosal HIF1α pathway was most affected by intestinal location and inflammatory status. Especially, ileal mucosal TFRC expression, encoding the transferrin receptor TFR1, was increased in inflamed tissue (p < 0.001), and further enhanced in ID. Accordingly, TFRC expression in inflamed tissue associated negatively with serum iron levels, which was not observed in the non-inflamed mucosa. The HIF1α pathway agonist DMOG increased TFRC expression in Caco-2 cells, which was blunted in HIF1A-null cells. Conclusion: We demonstrate that inflammation and anatomical location primarily determine HIF1α pathway activation and downstream TFRC expression in the intestinal mucosa. IBD patients with ID may benefit from treatment with HIF1α-agonists by 1) increasing TFRC-mediated iron absorption in non-inflamed tissue and 2) decreasing mucosal inflammation, thereby improving their responsiveness to oral iron supplementation

    Successful futures, successful curriculum: What can Wales learn from international curriculum reforms?

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    The proposed Curriculum for Wales 2022 presents a bold new vision for curriculum, teaching and learning. Together with its focus on four key purposes, it affords substantially more flexibility and autonomy to teachers and schools, positions learners as central to curriculum decision making, promotes active forms of pedagogy and 21st century skills, and reduces specification of curriculum content. Like other ‘new curriculum’ examples around the world, it brings with it a complex set of interacting curricular elements, with challenges including curriculum design capability and the agency required of those working with the curriculum. In this article we discuss challenges and opportunities for this curriculum reform in light of international curriculum experience. In particular, we highlight the need for attention to the accountability, professional learning, and social network context necessary for the realization of national curriculum aspirations in Wales

    The impact of delayed development on the quality of life of adults with end-stage renal disease since childhood

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    Little is known about the impact of the course of life of children with end-stage renal disease (ESRD) on their quality of life in adulthood. We therefore assessed the course of life of adult patients with onset of ESRD at an age of <15 years between 1972 and 1992 and compared it with that of the general population. Furthermore, we explored how course of life is associated with quality of life (QoL) in young adulthood. A total of 75 young adult patients who had had ESRD since childhood, aged between 20 years and 30 years, completed the RAND-36 Health Survey and a questionnaire, which retrospectively assesses the achievement of development milestones. Patients achieved fewer milestones than peers with respect to autonomy, social, and psycho-sexual development, and displayed less risk behaviour. Patients who achieved fewer social milestones while growing up experienced more emotional problems and less vitality, and they had a lesser overall mental quality of life. Paediatric nephrologists should pay more attention to the development of social and independent functioning of children with ESRD in order to prepare them for active participation in society in adult life. © IPNA 2006

    Establishing the phenotypic spectrum of ZTTK syndrome by analysis of 52 individuals with variants in SON

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    Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome, an intellectual disability syndrome first described in 2016, is caused by heterozygous loss-of-function variants in SON. Its encoded protein promotes pre-mRNA splicing of many genes essential for development. Whereas individual phenotypic traits have previously been linked to erroneous splicing of SON target genes, the phenotypic spectrum and the pathogenicity of missense variants have not been further evaluated. We present the phenotypic abnormalities in 52 individuals, including 17 individuals who have not been reported before. In total, loss-of-function variants were detected in 49 individuals (de novo in 47, inheritance unknown in 2), and in 3, a missense variant was observed (2 de novo, 1 inheritance unknown). Phenotypic abnormalities, systematically collected and analyzed in Human Phenotype Ontology, were found in all organ systems. Significant inter-individual phenotypic variability was observed, even in individuals with the same recurrent variant (n = 13). SON haploinsufficiency was previously shown to lead to downregulation of downstream genes, contributing to specific phenotypic features. Similar functional analysis for one missense variant, however, suggests a different mechanism than for heterozygous loss-of-function. Although small in numbers and while pathogenicity of these variants is not certain, these data allow for speculation whether de novo missense variants cause ZTTK syndrome via another mechanism, or a separate overlapping syndrome. In conclusion, heterozygous loss-of-function variants in SON define a recognizable syndrome, ZTTK, associated with a broad, severe phenotypic spectrum, characterized by a large inter-individual variability. These observations provide essential information for affected individuals, parents, and healthcare professionals to ensure appropriate clinical management

    Automated Analysis in Feature Modelling and Product Configuration

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    The automated analysis of feature models is one of the thriving topics of research in the software product line and variability management communities that has attracted more attention in the last years. A recent literature review reported that more than 30 analysis operations have been identi ed and di erent analysis mechanisms have been proposed. Product con guration is a well established research eld with more than 30 years of successful applications in di erent industrial domains. Our hypothesis, that is not really new, is that these two independent areas of research have interesting synergies that have not been fully explored. To try to explore the potential synergies systematically, in this paper we provide a rapid review to bring together these previously disparate streams of work. We de ne a set of research questions and give a preliminary answer to some of them. We conclude that there are many research opportunities in the synergy of these independent areas.Ministerio de Ciencia e Innovación TIN2009- 07366Junta de Andalucía TIC-590

    Randomised controlled trial of tailored interventions to improve the management of anxiety and depressive disorders in primary care

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    Contains fulltext : 96261.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Anxiety and depressive disorders are highly prevalent disorders and are mostly treated in primary care. The management of these disorders by general practitioners is not always consistent with prevailing guidelines because of a variety of factors. Designing implementation strategies tailored to prospectively identified barriers could lead to more guideline-recommended care. Although tailoring of implementation strategies is promoted in practice, little is known about the effect on improving the quality of care for the early recognition, diagnosis, and stepped care treatment allocation in patients with anxiety or depressive disorders in general practice. This study examines whether the tailored strategy supplemented with training and feedback is more effective than providing training and feedback alone. METHODS: In this cluster randomised controlled trial, a total of 22 general practices will be assigned to one of two conditions: (1) training, feedback, and tailored interventions and (2) training and feedback. The primary outcome measure is the proportion of patients who have been recognised to have anxiety and/or depressive disorder. The secondary outcome measures in patients are severity of anxiety and depressive symptoms, level of functioning, expectation towards and experience with care, quality of life, and economic costs. Measures are taken after the start of the intervention at baseline and at three- and six-month follow-ups. Secondary outcome measures in general practitioners are adherence to guideline-recommended care in care that has been delivered, the proportion of antidepressant prescriptions, and number of referrals to specialised mental healthcare facilities. Data will be gathered from the electronic medical patient records from the patients included in the study. In a process evaluation, the identification of barriers to change and the relations between prospectively identified barriers and improvement interventions selected for use will be described, as well as the factors that influence the provision of guideline-recommended care. DISCUSSION: It is hypothesised that the adherence to guideline recommendations will be improved by designing implementation interventions that are tailored to prospectively identified barriers in the local context of general practitioners. Currently, there is insufficient evidence on the most effective and efficient approaches to tailoring, including how barriers should be identified and how interventions should be selected to address the barriers. TRIAL REGISTRATION: NTR1912
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