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The discovery of high-temperature superconductivity in a layered iron arsenide has led to an intensive search to optimize the superconducting properties of iron-based superconductors by changing the chemical composition of the spacer layer between adjacent anionic iron arsenide layers. Superconductivity has been found in iron arsenides with cationic spacer layers consisting of metal ions (for example, Li+, Na+, K+, Ba2+) or PbO- or perovskite-type oxide layers, and also in Fe1.01Se (ref. ) with neutral layers similar in structure to those found in the iron arsenides and no spacer layer. Here we demonstrate the synthesis of Lix(NH2)y(NH3)1?yFe2Se2 (x~0.6; y~0.2), with lithium ions, lithium amide and ammonia acting as the spacer layer between FeSe layers, which exhibits superconductivity at 43(1)?K, higher than in any FeSe-derived compound reported so far. We have determined the crystal structure using neutron powder diffraction and used magnetometry and muon-spin rotation data to determine the superconducting properties. This new synthetic route opens up the possibility of further exploitation of related molecular intercalations in this and other systems to greatly optimize the superconducting properties in this family. [ABSTRACT FROM AUTHOR]

Purpose Student radiographers must possess certain abilities to progress in their training; these can be assessed in various ways. Bandura's social cognitive theory identifies self-efficacy as a key psychological construct with regard to how people adapt to environments where new skills are developed. Use of this construct is common in health care literature but little has been noted within radiographic literature. The authors sought to develop a self-efficacy scale for student radiographers. Method The scale was developed following a standard format. An initial pool of 80 items was generated and psychometric analysis was used to reduce this to 68 items. Radiography students drawn from 7 universities were participants (N=198) in validating the scale. Results The psychometric properties of the scale were examined using analysis of variance (ANOVA), factor analysis and item analysis. ANOVA demonstrated an acceptable level of known group validity: first-year, second-year, and third-year students all scored significantly differently (P=.035) from one another. Factor analysis identified the most significant factor as confidence in image appraisal. The scale was refined using item and factor analysis to produce the final 25-item scale. Conclusion This is the first published domain-specific self-efficacy scale validated specifically for student radiographers. In its current format it may have pedagogical utility. The authors currently are extending the work to add to the scale's validity and embedding it into student training to assess its predictive value. [ABSTRACT FROM AUTHOR]

Phenylsilsesquioxane fluid (PSF) is used widely in the personal care industry and is a common component of skin and oral care products. The potential developmental toxicity of PSF was evaluated in rats and rabbits. Groups of 25 sperm-positive Sprague-Dawley rats (Taconic Farms) and 15 sperm-positive New Zealand White rabbits (HRP) were administered dose levels of 50, 500, or 1000 mg/kg PSF in corn oil. Vehicle control groups of equal size were administered corn oil alone. Rats were dosed daily (5 ml/kg) on gestation d 6–15 and sacrificed on gestation d 20, while rabbits were dosed daily (1.5 ml/kg) on gestation d 6–18 and sacrificed on gestation d 29. The fetuses were removed by cesarean section and examined for gross external, visceral, cephalic, and skeletal anomalies. No treatment-related clinical signs of toxicity were observed. No marked effects upon maternal food consumption, body weight, body weight gain, or uterus or liver weight were detected. Fetal viability and body weight, as well as developmental endpoints, were unaffected by treatment. Accordingly, exposure of pregnant rats or rabbits to 50, 500, or 1000 mg/kg of PSF during the period of major organogenesis did not result in any biologically significant adverse or teratogenic effects in the dams or fetuses. [ABSTRACT FROM AUTHOR]

Studies reported here assessed the potential adverse effects of silicone gel, Dow Corning Q7-2159A, on general reproduction and fetal development in male and female Charles River CD rats and New Zealand white rabbits. Two control and three treatment groups of 30 male and 30 female rats and 25 female rabbits per group were used in the one-generation reproduction and developmental toxicity studies, respectively. The silicone gel was implanted subcutaneously in two flank sites at dosage levels of 3, 10, and 30 ml/kg. The highest dose was selected on the basis of likely human body burden. Control groups received either sterile saline or carboxymethylcellulose solution in two flank implantation sites. The control and test articles were implanted in male and female rats 61 and 47 days, respectively, prior to mating (in the rat reproduction study) and approximately 42 days prior to insemination of female rabbits (in the rabbit developmental toxicity study). There were no treatmentrelated effects on F parental general conditions and reproductive performance, F neonatal viability, or growth in the rat reproduction study. No maternal nor developmental effects, including teratogenicity, were observed in rabbits in the groups implanted with Q7-2159A gel in the developmental toxicitystudy. [ABSTRACT FROM PUBLISHER]

The purpose of these studies was to assess the potential adverse effects of silicone breast implant envelope elastomer on general reproduction and fetal development in rats and rabbits. One control and one treatment group of 30 male and 30 female Charles River CD rats and 25 inseminated New Zealand white rabbits per group were used in the one-generation reproductive and developmental toxicity studies, respectively. Two 1.2-cm discs of silicone elastomer were subcutaneoulsy implanted in one site in the left flank and one site in the right-flank of the treated group of rats, while four 2.5-cm discs were implanted in two sites in the left flank and two sites in the right flank of the treated group of rabbits. The size of the elastomer implants was chosen to approximate the expected body burden of women with breast implants. The control animlas in both studies received subcutaneous implantion of either 1.2- or 2.5-cm discs of polyethylene of the same number in the same locations. The control and tests articles were implanted in the male and female rats at 61 and 47 days, respectively, prior to mating (in the rat reproduction study) and approximately 42 days prior to insemination of femalel rabbits (in the rabbit developmental toxicity study). Subcutaneously implanted discs of silicone breast implant envelope elastomer did not induce maternal or devlopmental toxicity before or during pregnancy or during lactation, did not cause any adverse effects on the parents or neonates, and did not impair reproductive performance in the rat reproduction study. No maternal toxicity or adverse developmental effects including teratogenicity, were observed in the treated groups in the rabbit developmental toxicity study. [ABSTRACT FROM PUBLISHER]

Personal values influence goals and motivate actions. The case study reported in this paper explored whether an understanding of values would provide a useful framework to guide the co‐creation of the undergraduate cognitive psychology curriculum at a UK University. A design team composed of staff and students ran two co‐creation workshops to explore underlying values. These values were translated into curriculum ideas which were then shared via an online survey to students and staff for feedback. The activities revealed a set of values that were salient when imagining future curriculum designs: feeling stimulated, choice and autonomy, developing competence, feeling safe and secure, community and fairness. In addition, a deeper value layer was visible which reflected participants' orientations to learning and education. We describe our process for eliciting values and the intertwined and iterative relationship between value elicitation and a co‐created curriculum. We also reflect on the position of co‐creation within the value landscape of higher education and the social dynamics of staff‐student partnerships. We argue that whilst using values to frame co‐creation allows for deeper insight into how to embed curriculum re‐innovation, it is important to attend to the value system of co‐creation and those who do not participate. [ABSTRACT FROM AUTHOR]

Solid solutions between the known compounds Ca 2 FeO 3 Cu Ch and Sr 2 FeO 3 Cu Ch (Ch ​= ​S, Se) in which there are two fairly similar sites (8 and 9 coordinate) for the alkaline earth cations are not attainable under standard high temperature solid state syntheses under thermodynamic control. Instead compounds with greater condensation of FeO 5 square pyramids form as these afford one 8-coordinate site and one 12-coordinate site for the alkaline earths which is better suited to the size-mismatched cations in the compounds Sr 3- x Ca x Fe 2 O 5 Cu 2 Ch 2 (Ch ​= ​S, Se; x ​= ​1, 2). Sr 2 CaFe 2 O 5 Cu 2 S 2 , SrCa 2 Fe 2 O 5 Cu 2 S 2 , Sr 2 CaFe 2 O 5 Cu 2 Se 2 and SrCa 2 Fe 2 O 5 Cu 2 Se 2 all crystallise in the tetragonal space group I 4/ mmm with two formula units in the unit cell with the crystal structure first described for Sr 3 Fe 2 O 5 Cu 2 S 2. Oxide slabs composed of vertex-sharing FeO 5 square pyramids are separated by Cu 2 Ch 2 anti-fluorite-type layers. The larger Sr2+ ions have a strong preference for the 12-coordinate site in the oxide slabs, while Ca2+ cations dominate the 8-coordinate sites separating the oxide and chalcogenide slabs. Powder neutron diffraction reveals that all the compounds display antiferromagnetic long range ordering of the Fe3+ moments with ordering temperatures well above room temperature and exceeding 526 ​K in the case of Ca 2 SrFe 2 O 5 Cu 2 Se 2. Image 1 • Novel iron oxide chalcogenides with Ca2+/Sr2+ ordering synthesised. • The presence of differently sized cations dictates the structure adopted. • Sr2+ cations prefer the larger alkaline earth metal site; Ca2+ favour the smaller site. • Long range antiferromagnetic ordering persists well above room temperature. • Magnetic ordering model consists of tilted moments which reorientate upon heating. [ABSTRACT FROM AUTHOR]

Polycrystalline samples of the monoclinic perovskites CaLa 2 Ni 2- x Cu x WO 9 (x ​= ​0.25 and 0.5) have been prepared and characterised by neutron diffraction and magnetometry. The Ni2+, Cu2+ and W6+ cations are partially ordered over two crystallographically-distinct six-coordinate sites such that one is ~63% occupied by W6+ and both are occupied by Ni2+ and Cu2+ in a ratio of (2- x): x. The composition x ​= ​0.25 behaves as a spin glass below 35 ​K whereas x ​= ​0.5 is ferrimagnetic below 120 ​K with an ordered moment of 0.774(5) μ B per magnetic cation. The atomic moments order in a G-type pattern and the imbalance in the number of magnetic cations on the two sites results in a net magnetisation. A perovskite spin glass becomes ferrimagnetic when Cu2+ replaces Ni2+. Image 1 • Spin glass to ferrimagnetic transition as a function of composition. • Cation-ordered perovskite. • Magnetic structure determination by neutron diffraction. [ABSTRACT FROM AUTHOR]

Mixed-valent transition metal compounds display complex structural, electronic and magnetic properties which can often be exquisitely tuned. Here the charge-ordered state of stoichiometric CaFe3O5 is probed using neutron powder diffraction, Monte Carlo simulation and symmetry analysis. Magnetic ordering is dominated by the formation of ferromagnetic Fe3+–Fe2+–Fe3+ trimers which are evident above the magnetic ordering transition. Between TN = 289 K and 281 K an incommensurate magnetically ordered phase develops due to magnetic frustration, but a spin Jahn-Teller distortion lifts the frustration and enables the magnetic ordering to lock in to a charge-ordered commensurate state at lower temperatures. Stoichiometric CaFe3O5 exhibits single phase behaviour throughout and avoids the phase separation into two distinct crystallographic phases with different magnetic structures and Fe valence distributions reported recently, which likely occurs due to partial Fe2+ for Ca2+ substitution. This underlines the sensitivity of the magnetism and chemistry of these mixed-valent systems to composition. A significant challenge in understanding the behaviour of strongly correlated materials is their sensitivity to composition. Here the authors show that stoichiometric CaFe3O5 avoids the electronic phase separation reported in a non-stoichiometric sample, and also exhibits an incommensurate magnetic phase. [ABSTRACT FROM AUTHOR]

Aim: Expanding and sustaining student nurse placements outside of the acute sector is a universal challenge. This paper aims to evaluate the Care Home Education Facilitator Role introduced in one area of Wales, United Kingdom, and to report on the outcomes achieved from this novel role. Methods: Semi‐structured interviews were undertaken with key stakeholders including the Care Home Education Facilitator postholder leading the pilot, care home managers, higher education institutions' placement managers/coordinators, student nurses and national health service staff. Results: Five key areas were identified, which included timing of introducing the post and establishing a clear rationale and understanding of the intention of the role. The benefits, challenges and suggested improvements to the Care Home Education Facilitator initiative are provided. Conclusion: Introducing the role of the Care Home Education Facilitator to work closely with key stakeholders resulted in increased placements for student nurses, but investing time in developing relationships with these stakeholders was critical to the success of the role. Summary statement: What is already known about this topic? There is a universal shortage of clinical placements for nursing students, particularly within a care home setting.The number of studies exploring how we might grow the number of nurses needed in this setting is limited. What this paper adds? This study evaluated a novel initiative introduced in South Wales, United Kingdom, that focuses on the development of nursing placements in the care home setting.Engaging with stakeholders involved in the development and implementation of the Care Home Education Facilitator initiative, a roadmap was provided to illustrate the stepped approach required to support an active care home placement including key governance arrangements. The implications of this paper: For those involved in identifying and developing student placements, this study provides valuable insight to a role that can help increase student numbers in a care setting often overlooked.It identifies viable career options for nurses at the point of registration.The role assists with widening networks for the care homes across health and social care sectors. [ABSTRACT FROM AUTHOR]

Abstract: The effect of the isovalent substitution of Sr2+ by Ca2+ on the structure and superconducting properties of Sr2−x Ca x VO3FeAs is described in the compositional range 0≤x≤0.5. SQUID magnetometry measurements reveal that after an initial increase in T c , which is maximised at 29.5K in Sr1.95Ca0.05VO3FeAs, a rapid suppression of superconductivity is observed with increasing x. XANES spectra of Sr2−x Ca x VO3FeAs collected on the Fe and V absorption K-edges show that the position of both edges are invariant with composition within the experimental uncertainty. A combination of synchrotron X-ray powder diffraction and neutron powder diffraction techniques is used to rationalise the observed changes in T c with x, in terms of changes to the structure of the FeAs layer upon partial Ca substitution. These findings demonstrate that superconductivity in the Fe-based superconductors is extremely sensitive to the crystal structure with T c maximised in samples with regular FeAs4-tetrahedra. [Copyright &y& Elsevier]

Abstract Employing a triangulated design to explore psychophysiological indices of cognitive style, the study investigated the validity of the intuition-analysis dimension of cognitive style and its associated construct measure, the Cognitive Style Index (CSI). Participants completed a comparative visual search (CVS) task whilst changes in hemodynamic concentrations in the prefrontal cortex (PFC) were monitored using functional near-infrared spectroscopy and eye movements were recorded together with task performance measures of response time and accuracy. Results revealed significant style-related differences in response time and number of saccades. Analysts were characterized by fewer saccadic eye movements and quicker response times—but with comparable accuracy scores—compared to intuitives, suggesting a more efficient visual search strategy and decision-making style on the experimental task. No style-related differences in neural activation were found, suggesting that differences were not mediated by style-specific variations in brain activation or hemispheric lateralization. Task-evoked neural activation—compared with baseline resting state—represented the value of PFC-based neural activation measures in studies of cognitive processing. Findings demonstrated style-related differences supporting the intuition-analysis dimension of cognitive style and the validity of the CSI as a psychometric measure of style. The potential value of valid psychometric measures of cognitive style in applied areas is highlighted. Highlights • Cognitive style associated with differences when completing a visual search task. • Analysts exhibit a more efficient visual search strategy and decision-making style. • Cognitive style does not affect accuracy scores on a visual search task. • No style-specific variations in brain activation or hemispheric lateralization. • Intuition-analysis dimension measured by the Cognitive Style Index is supported. [ABSTRACT FROM AUTHOR]

We use in situ synchrotron X-ray diffraction measurements to monitor the solvothermal crystallization mechanism of the aperiodic metal-organic framework TRUMOF-1. Following an initial incubation period, TRUMOF-1 forms as a metastable intermediate that subsequently transforms into an ordered product with triclinic crystal symmetry. We determine the structure of this ordered phase, which we call msw-TRUMOF-1, and show that it is related to TRUMOF-1 through topotactic reorganization of linker occupancies. Our results imply that the connectivity of TRUMOF-1 can be reorganized, as required for data storage and manipulation applications.

We report the magnetic behavior of the hybrid perovskites [Gua]Mn 1- x Fe 2 x /3 □ x /3 (HCOO) 3 (0 ≤ x ≤ 0.88), showing that vacancy ordering drives bulk ferrimagnetism for x > 0.6. The behavior is rationalized in terms of a simple microscopic model of percolation-induced ferrimagnetism. Monte Carlo simulations driven by this model reproduce the experimental dependence of magnetic susceptibility on x and show that, at intermediate compositions, domains of short-range vacancy order lead to the emergence of local magnetization. Our results open up a new avenue for the design of multiferroic hybrid perovskites.