112 research outputs found
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Fostering Inquiry and Creativity in Early Years STEM Education: Policy Recommendations from the <i>Creative Little Scientists</i> Project
Creative Little Scientists was a 30-month (2011-2014) EU/FP7-funded research project focusing on the synergies between early years science and mathematics education and the development of childrenâs creativity, in response to increasing interest in these areas in European educational policy. Using a variety of methods, including desk research, a teacher survey and classroom-based fieldwork, the research provided insights into whether and how childrenâs creativity is fostered and appropriate learning outcomes, including childrenâs interest, emerge. Based on these and ongoing collaboration and dialogue with participants and other stakeholders the project proposed recommendations for policy and teacher education. This paper presents these recommendations and the research on which they were based. Throughout the study, mixed methods were employed, combining quantitative approaches used in surveys of policy and teachersâ views based on a list of factors, alongside qualitative approaches employed in case studies of classroom practice. A strong conceptual framework developed at the start of the project guided data collection and analysis, as well as the presentation of findings and the development of policy recommendations, thus ensuring the latterâs strong and consistent relationship with the relevant theoretical knowledge, the comparative research, analysis of classroom practices and the production of guidelines for teacher education
A combined "electrochemical-frustrated Lewis pair" approach to hydrogen activation: surface catalytic effects at platinum electrodes
Herein, we extend our âcombined electrochemicalâfrustrated Lewis pairâ approach to include Pt electrode surfaces for the first time. We found that the voltammetric response of an electrochemicalâfrustrated Lewis pair (FLP) system involving the B(C6F5)3/[HB(C6F5)3]â redox couple exhibits a strong surface electrocatalytic effect at Pt electrodes. Using a combination of kinetic competition studies in the presence of a H atom scavenger, 6-bromohexene, and by changing the steric bulk of the Lewis acid borane catalyst from B(C6F5)3 to B(C6Cl5)3, the mechanism of electrochemicalâFLP reactions on Pt surfaces was shown to be dominated by hydrogen-atom transfer (HAT) between Pt, [Pt[BOND]H] adatoms and transient [HB(C6F5)3]â
electrooxidation intermediates. These findings provide further insight into this new area of combining electrochemical and FLP reactions, and proffers additional avenues for exploration beyond energy generation, such as in electrosynthesis
Modeling item-level spelling variance in adults : Providing further insights into lexical quality
Purpose
The lexical quality (LQ) hypothesis predicts that a skilled readerâs lexicon will be inhabited by a range of low- to high-quality items, and the probability of representing a word with high quality varies as a function of person-level, word-level, and item-specific variables. These predictions were tested with spelling accuracy as a gauge of LQ.
Method
Item-response based crossed random effects models explored simultaneous contributions of person-level (e.g. participantâs decoding skill), word-level (e.g. wordâs transparency rating), item-specific (e.g. participantâs familiarity with specific word), and person-by-word interaction predictors (e.g. decoding by transparency rating interaction) to the spelling of 25 commonly misspelled irregular English words in 61 undergraduate university students (M = 19.4âyears, 70.49% female, 39.34% Hispanic, 81.97% White).
Results
Substantial variance among individuals in item-level spelling accuracy was accounted for by person-level decoding skill; item-specific familiarity, proportion of schwas correctly represented, and correctly identifying the word from its mispronunciation; and an interaction of transparency rating by general decoding skill.
Conclusions
Consistent with the LQ hypothesis, results suggest that oneâs ability to form a high-quality lexical representation of a given word depends on a complex combination of person-level abilities, word-level characteristics, item-specific experiences, and an interaction between person- and word-level influences
Humidified and standard oxygen therapy in acute severe asthma in children (HUMOX): A pilot randomised controlled trial.
BackgroundOxygen (O2) is a mainstay of treatment in acute severe asthma but how it is administered varies widely. The objectives were to examine whether a trial comparing humidified O2 to standard O2 in children is feasible, and specifically to obtain data on recruitment, tolerability and outcome measure stability.MethodsHeated humidified, cold humidified and standard O2 treatments were compared for children (2-16 years) with acute severe asthma in a multi-centre, open, parallel, pilot randomised controlled trial (RCT). Multiple outcomes were assessed.ResultsOf 258 children screened, 66 were randomised (heated humidified O2 n = 25; cold humidified O2 n = 21; standard O2 n = 20). Median (IQR) length of stay (hours) in hospital was 37.9 (29.1), 52 (35.4) and 49.1 (29.7) for standard, heated humidified and cold humidified respectively and time (hours) on O2 was 15.9 (9.4), 13.6 (14.9) and 13.1 (14.9) for the three groups respectively. The mean (standard deviation) time (hours) taken to step down nebulised to inhaled treatment was 5.6 (14.3), 35.1 (28.2) and 32.7 (20.1). Asthma Severity Score decreased in all three groups similarly, although missing data prevented complete analysis. Humidified O2 was least well tolerated with eight participants discontinuing their randomised treatment early. An important barrier to recruitment was research nurse availability.ConclusionAlthough, the results of this pilot study should not be extrapolated beyond the study sample and inferential conclusions should not be drawn from the results, this is the first RCT to compare humidified and standard O2 therapy in acute severe asthmatics of any age. These findings and accompanying screening data show that a large RCT of O2 therapy is feasible. However, challenges associated with randomisation and data collection should be addressed in any future trial design
Gremlin 1 identifies a skeletal stem cell with bone, cartilage, and reticular stromal potential
The stem cells that maintain and repair the postnatal skeleton remain undefined. One model suggests that perisinusoidal mesenchymal stem cells (MSCs) give rise to osteoblasts, chondrocytes, marrow stromal cells, and adipocytes, although the existence of these cells has not been proven through fate-mapping experiments. We demonstrate here that expression of the bone morphogenetic protein (BMP) antagonist gremlin 1 defines a population of osteochondroreticular (OCR) stem cells in the bone marrow. OCR stem cells self-renew and generate osteoblasts, chondrocytes, and reticular marrow stromal cells, but not adipocytes. OCR stem cells are concentrated within the metaphysis of long bones not in the perisinusoidal space and are needed for bone development, bone remodeling, and fracture repair. Grem1 expression also identifies intestinal reticular stem cells (iRSCs) that are cells of origin for the periepithelial intestinal mesenchymal sheath. Grem1 expression identifies distinct connective tissue stem cells in both the bone (OCR stem cells) and the intestine (iRSCs)
A base-free synthetic route to anti-bimetallic lanthanide pentalene complexes
We report the synthesis and structural characterisation of three homobimetallic complexes featuring divalent lanthanide metals (Ln = Yb, Eu and Sm) bridged by the silylated pentalene ligand [1,4-{SiiPr3}2C8H4]2â (= Pnâ ). Magnetic measurements and cyclic voltammetry have been used to investigate the extent of intermetallic communication in these systems, in the context of molecular models for organolanthanide based conducting materials
Which outcomes should be used in future bronchiolitis trials? Developing a bronchiolitis core outcome set using a systematic review, Delphi survey and a consensus workshop
Objectives The objective of this study was to develop a core outcome set (COS) for use in future clinical trials in bronchiolitis. We wanted to find out which outcomes are important to healthcare professionals (HCPs) and to parents and which outcomes should be prioritised for use in future clinical trials.Design and setting The study used a systematic review, workshops and interviews, a Delphi survey and a final consensus workshop.Results Thirteen parents and 45 HCPs took part in 5 workshops; 15 other parents were also separately interviewed. Fifty-six items were identified from the systematic review, workshops and interviews. Rounds one and two of the Delphi survey involved 299 and 194 participants, respectively. Sixteen outcomes met the criteria for inclusion within the COS. The consensus meeting was attended by 10 participants, with representation from all three stakeholder groups. Nine outcomes were added, totalling 25 outcomes to be included in the COS.Conclusion We have developed the first parent and HCP consensus on a COS for bronchiolitis in a hospital setting. The use of this COS will ensure outcomes in future bronchiolitis trials are important and relevant, and will enable the trial results to be compared and combined
Bonding in complexes of bis(pentalene)di-titanium, Ti2(C8H6)2
Bonding in the bis(pentalene)di-titanium âdouble-sandwichâ species Ti2Pn2 (Pn = C8H6) and its interaction with other fragments have been investigated by xdensity functional calculations and fragment analysis. Ti2Pn2 with C2v symmetry has two metal-metal bonds and a low-lying metal based empty orbital, all three frontier orbitals having a1 symmetry. The latter may be regarded as being derived by symmetric combinations of the classic three frontier orbitals of two bent bis(cyclopentadienyl) metal fragments. Electrochemical studies on Ti2Pnâ 2 (Pnâ = C8H4{SiiPr3-1,4}2) reveal a one-electron oxidation, and the formally mixed-valence Ti(II)-Ti(III) cationic complex [Ti2Pnâ 2][B(C6F5)4] has been structurally characterised. Theory indicates an S = Âœ ground state electronic configuration for the latter, confirmed by EPR spectroscopy and SQUID magnetometry.
Carbon dioxide binds symmetrically to Ti2Pn2 preserving C2v symmetry, as does carbon disulfide. The dominant interaction in Ti2Pn2CO2 is Ï donation into the LUMO of bent CO2 and donation from the O atoms to Ti2Pn2 is minimal, whereas in Ti2Pn2CS2 there is significant interaction with the S atoms. The bridging O atom in the mono(oxo) species Ti2Pn2O, however, employs all three O 2p orbitals in binding and competes strongly with Pn, leading to weaker binding of the carbocyclic ligand, and the sulfur analog Ti2Pn2S behaves similarly.
Ti2Pn2 is also capable of binding one, two and three molecules of carbon monoxide. The bonding demands of a single CO molecule are incompatible with symmetric binding and an asymmetric structure is found. The dicarbonyl adduct Ti2Pn2(CO)2 has Cs symmetry with the Ti2Pn2 unit acting as two MCp2 fragments. Synthetic studies show, that in the presence of excess CO a tricarbonyl complex Ti2Pnâ 2(CO)3 is formed, which optimises to an asymmetric structure with two terminal CO ligands and one semi-bridging. Low temperature 13C NMR spectroscopy reveals a rapid dynamic exchange between the two bound CO sites and free CO
Historical textile dyeing with Genista tinctoria L.:a comprehensive study by UPLC-MS/MS analysis
Polyphenolic components from Genista species have been well characterised because of their potential as antioxidants and as therapeutic leads; however, the identification of dyer's greenweed (Genista tinctoria L.) in historical textiles has been the subject of only limited studies. This paper presents a comprehensive UPLC-PDA MS/MS study of reference and historical yarns dyed with this species. Several so far unreported dye components that could assist with the identification of this dye source, were characterised by MS/MS. Furthermore, the effect of photo-degradation and textile preparation techniques (such as over-dyeing) on the dye fingerprint was investigated and the results correlated with those obtained from historical samples from the Burrell and Bodleian collections, UK
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