bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical modeling of bubble dynamics in viscoelastic media with relaxation
Authors: Warnez M. T. , Johnsen E.
Published: June 2015

Cavitation occurs in a variety of non-Newtonian fluids and viscoelastic materials. The large-amplitude volumetric oscillations of cavitation bubbles give rise to high temperatures and pressures at collapse, as well as induce large and rapid deformation of the surroundings. In this work, we develop a comprehensive numerical framework for spherical bubble dynamics in isotropic media obeying a wide range of viscoelastic constitutive relationships. Our numerical approach solves the compressible Keller–Miksis equation with full thermal effects (inside and outside the bubble) when coupled to a highly generalized constitutive relationship (which allows Newtonian, Kelvin–Voigt, Zener, linear Maxwell, upper-convected Maxwell, Jeffreys, Oldroyd-B, Giesekus, and Phan-Thien-Tanner models). For the latter two models, partial differential equations (PDEs) must be solved in the surrounding medium; for the remaining models, we show that the PDEs can be reduced to ordinary differential equations. To solve the general constitutive PDEs, we present a Chebyshev spectral collocation method, which is robust even for violent collapse. Combining this numerical approach with theoretical analysis, we simulate bubble dynamics in various viscoelastic media to determine the impact of relaxation time, a constitutive parameter, on the associated physics. Relaxation time is found to increase bubble growth and permit rebounds driven purely by residual stresses in the surroundings. Different regimes of oscillations occur depending on the relaxation time.
Direct numerical simulation of a 30R long turbulent pipe flow at Re
τ = 3008
Authors: Ahn Junsun , Lee Jae Hwa , Lee Jin , Kang Ji-hoon , Sung Hyung Jin
Published: June 2015

A direct numerical simulation of a turbulent pipe flow at a high Reynolds number of Reτ = 3008 over a long axial domain length (30R) was performed. The streamwise mean velocity followed the power law in the overlap region (y+ = 90–300; y/R = 0.03–0.1) based on the power law indicator function. The scale separation of the Reynolds shear stresses into two components of small- and large-scale motions (LSMs) revealed that the LSMs in the outer region played an important role in constructing the constant-stress layer and the mean velocity. In the pre-multiplied energy spectra of the streamwise velocity fluctuations, the bimodal distribution was observed at both short and long wavelengths. The kx−1 region associated with the attached eddies appeared in λx/R = 2–5 and λx/y = 18–160 at y+ = 90–300, where the power law was established in the same region. The kz−1 region also appeared in λz/R = 0.3–0.6 at y+ = 3 and 150. Linear growth of small-scale energy to large-scale energy induced the kx−1 region at high Reynolds numbers, resulting in a large population of the LSMs. This result supported the origin of very-large-scale motions in the pseudo-streamwise alignment of the LSMs. In the pre-multiplied energy spectra of the Reynolds shear stress, the bimodal distribution was observed without the kx−1 region.
Surface optical and bulk acoustic phonons in the topological insulator, Bi2Se2Te
Authors: Mukhopadhyay Uditendu , Chaudhuri Dipanjan , Sarkar Jit , Singh Sourabh , Gopal Radha Krishna , Tammu Sandeep , Upadhya Prashanth C. , Mitra Chiranjib
Published: June 2015

We explore the phonon dynamics in thin films of the topological insulator material Bi2Se2Te using ultrafast pump-probe spectroscopy. The time resolved differential reflectivity in these films exhibit fast and slow oscillations. We have given a careful analysis of variation of phonon frequency as a function of film thickness, which we attribute to the existence of standing acoustic modes. However, no variation in the frequency of the optical phonon modes was found with film thickness. This indicates that the optical phonons intrinsically belong to the surface of topological insulators. The controllability of acoustic phonons by way of varying the film thickness will have tremendous implications in the application of these materials in low power spintronic device operating at room temperature.
Effects of polarization of polar semiconductor on electrical properties of poly(vinylidene fluoride-trifluoroethylene)/ZnO heterostructures
Authors: Yamada Hiroaki , Yoshimura Takeshi , Fujimura Norifumi
Published: June 2015

The electrical properties of heterostructures composed of poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) and ZnO with different crystallographic polarities, i.e., O- and Zn-polar ZnO, were investigated. Distinct differences in the capacitance-voltage and polarization-voltage characteristics between the P(VDF-TrFE)/O- and Zn-polar ZnO were obtained in the depletion regions of ZnO. The band configurations were determined by X-ray photoelectron spectroscopy (XPS) using a synchrotron radiation beam to analyze the differences in the electrical properties of the P(VDF-TrFE)/O- and Zn-polar ZnO. The XPS spectra indicated that the valence band maximum of P(VDF-TrFE) is 2.9 and 2.7 eV higher than Zn- and O-polar ZnO, respectively. Thus, both structures have staggered band configurations with large valence band offsets, and the spontaneous polarization of ZnO is less effective on the band lineup. The electrical properties of the P(VDF-TrFE)/ZnO heterostructures are modulated through carrier generation because of the polarization-mediated interface charges and the staggered band alignments of the P(VDF-TrFE)/ZnO with a large valence band offset.
Resonance frequency shift of strongly heated micro-cantilevers
Authors: Aguilar Sandoval Felipe , Geitner Mickael , Bertin Éric , Bellon Ludovic
Published: June 2015

In optical detection setups to measure the deflection of micro-cantilevers, part of the sensing light is absorbed, heating the mechanical probe. We present experimental evidences of a frequency shift of the resonant modes of a cantilever when the light power of the optical measurement set-up is increased. This frequency shift is a signature of the temperature rise and presents a dependence on the mode number. An analytical model is derived to take into account the temperature profile along the cantilever; it shows that the frequency shifts are given by an average of the profile weighted by the local curvature for each resonant mode. We apply this framework to measurements in vacuum and demonstrate that huge temperatures can be reached with moderate light intensities: a 1000 °C with little more than 10 mW. We finally present some insight into the physical phenomena when the cantilever is in air instead of vacuum.
Conservation biology of two endemic Beyeria species (Euphorbiaceae) from southern Western Australia
Authors: Vincent Brian J. , Barrett Sarah , Cochrane Anne , Plummer Julie A. , Renton Michael
Published: June 2015

Beyeria cockertonii Halford & R.J.F.Hend. and Beyeria villosa Halford & R.J.F.Hend. (Euphorbiaceae) are two short-range endemic monoecious congeners from southern Western Australia. We sought to determine whether life-history characteristics were responsible for their limited distribution and to identify aspects of their ecology that might render them vulnerable to current threatening processes. We investigated reproductive phenology in relation to climate, pollinator activity and synchronicity of male and female flowering. In addition seed dispersal, regeneration, demography and seed viability were examined and ex situ germination experiments conducted to determine seed-dormancy mechanisms. Flowering in the conservation-listed B. cockertonii was significantly correlated with temperature, whereas fruit set was correlated with pollinator abundance and movement; male and female flowering showed limited synchrony. The presence of soil-stored seeds lacking a caruncle at sites absent of adult plants of either species suggests that seed may be ant-dispersed (myrmecochory). Fresh seeds of B. cockertonii were significantly more viable than those of its more common congener, B. villosa (72 vs 0.5%, P < 0.001). Fresh B. cockertonii seeds would not germinate with an intact caruncle; caruncle removal elicited germination of 64% and 60% (10°C and 15°C, respectively). Aqueous smoke further stimulated germination to 72% and 83% germination (10°C and 15°C, respectively), providing a link between fire and germination. Beyeria villosa was affected by high levels of pre-dispersal predation (up to 70%) and seed abortion (88%) and appeared to have lower reproductive fitness than B. cockertonii. Life-history strategies did not explain the greater abundance and wider distribution of B. villosa than those of the conservation-listed B cockertonii, nor was the greater rarity of B. cockertonii fully explained by habitat specificity, with both species being restricted to ultra-mafic volcanic rock associated with Achaean greenstone. However, an apparent dependence of B. cockertonii on a specific insect pollinator from the family Miridae may render this species vulnerable to threatening processes.
Keep it local (and final): Remnant preferences in “let alone” ellipsis
Authors: Harris Jesse A. , Carlson Katy
Published: June 2015

The let alone construction ( John can't run a mile, let alone a marathon) differs from standard coordination structures (with and or but) by requiring ellipsis of the second conjunct—for example, a marathon is the remnant of an elided clause [ John run a marathon]. In support of an ellipsis account, a corpus study of British and American English finds that let alone exhibits a Locality bias, as the second conjunct preferentially contrasts with the nearest lexical item of the same syntactic type. Two self-paced reading studies show that the Locality bias is active during online processing, but must be reconciled with indicators of semantic contrast and discourse information. Further, a sentence-rating study shows that the Locality bias interacts with a Finality bias that favours placing the let alone phrase at the end of a clause, which sometimes necessitates a nonlocal contrast. Together, the results show how a general bias in ellipsis for local contrasts is affected by discourse demands, such as the need for scalar contrast imposed by let alone, thereby offering a window into how possibly divergent syntactic and discourse constraints impact sentence processing.
If only they knew better: strengthening knowledge systems for social development?
Authors: Narayanaswamy Lata
Published: June 2015

Information and knowledge are frequently upheld as the cornerstones of development programmes. Poverty reduction measures delivered through social policies are frequently premised on the need to ensure that both users and providers of services have access to information. In contexts where poor and marginalised groups are largely excluded from knowledge access and uptake, Southern-based civil society is called upon to act as an interlocutor to leverage knowledge on their behalf to achieve social welfare objectives. Ensuring that the greatest number of people have access to timely and relevant information, promoted as part of global-level discourses on the desirability of fostering a “knowledge society”, is presumed to contribute, for instance, to the capacity of citizens to uphold government accountability, ensure access to entitlements or protect basic rights. This paper critically analyses the capacity of knowledge, delivered primarily though not exclusively through new information and communications technologies and leveraged through Southern-based civil society acting as intermediaries, to achieve social policy objectives in development.
Arakelov motivic cohomology II
Authors: Scholbach Jakob
Published: June 2015

We show that the constructions done in part I generalize their classical counterparts: firstly, the classical Beilinson regulator is induced by the abstract Chern class map fromBGL\operatorname {BGL}to the Deligne cohomology spectrum. Secondly, Arakelov motivic cohomology is a generalization of arithmeticKK-theory and arithmetic Chow groups. For example, this implies a decomposition of higher arithmeticKK-groups in its Adams eigenspaces. Finally, we give a conceptual explanation of the height pairing: it is the natural pairing of motivic homology and Arakelov motivic cohomology.
The Received Concept of the Employer
Authors: Adams-Prassl Jeremias
Published: June 2015

This chapter conceptualizes the received concept of the employer in English law. Moving beyond a series of frequently unspoken and unchallenged assumptions, the analysis reveals two competing conceptual strands in the existing case law: the concept is shaped by a range of external factors (such as language and fact patterns, contract law and the corporate veil) as a unitary one. At the same time, there is little evidence in the traditional employment status tests to suggest an inherent need for the employer always to be a singular entity. Indeed, the common law frequently betrays a strongly multi-functional concept of the employer. Five different groups of such functions are identified and illustrated. The chapter concludes by suggesting that the tension between these different strands can quickly come to the fore in multilateral work settings, once more than one entity becomes involved in the direct management of employment relationships.
The Shared Exercise of Employer Functions Across MultipleLociof Control
Authors: Adams-Prassl Jeremias
Published: June 2015

This chapter illustrates how developments in modern enterprise organization, from agency work to corporate groups and activist investors such as Private Equity funds, are increasingly building on complex multilateral arrangements, thus rapidly moving the majority of employment relationships outside the traditional unitary paradigm. Whilst the different structures surveyed on the basis of the author’s fieldwork reports and relevant academic literature vary considerably in their technical setup and day-to-day operation, they are united in the sheer complexity and variety of shared or parcelled-out management of work. As soon as employer functions are exercised from more than one locus of management control or divided across several legal entities, the tension inherent in the traditional concept of the employer becomes a challenge to the coherence of employment law coverage.
A Functional Concept
Authors: Adams-Prassl Jeremias
Published: June 2015

Shifting from the previous analytical-descriptive approach into an openly normative attempt fundamentally to reconceptualize the concept of the employer, this chapter analyses the received multi-functional limb to show how a careful extension to a fully functional concept could be achieved. A first section develops a detailed theoretical account of the proposed functional typology, noting in particular its roots in the existing approach and testing its ability to draw clear outer boundaries of the application of employment law norms. Different examples for the practical operation of such a functional concept are explored in the following section, drawing on a broad range of existing avenues from both the common law (implied contracts) and different models of statutory regulation (discrimination law in the Equality Act 2010, and statutory Health and Safety provisions), before concluding with a positive evaluation of the proposed modifications of the multi-functional strand against previously developed criteria.
The IASB’s Vexed Relation with Europe
Authors: Camfferman Kees , Zeff Stephen A.
Published: June 2015

The EU’s commitment to IFRSs was confirmed with the actual adoption of the standards in practice, beginning in 2005. The European Commission encouraged other jurisdictions to adopt or converge with IFRSs, through its requirement that non-EU companies listed in the EU should use IFRSs or national standards deemed equivalent with IFRSs. Nonetheless, the relationship between the IASB and the EU remained tense because of continuing controversy over some of the IASB’s technical work. The European Parliament actively involved itself in discussions of the IASB’s governance and accountability. By delaying the endorsement of IFRS 8 on segment reporting, the Parliament declared its authority to intervene in the endorsement of individual standards.
Assessing the inter-rater reliability and agreement of a hybrid assessment framework in the Emergency Department
Authors: Gan Han Nee , Tiah Ling , Lee Shu Woan , Lee Wee Yee
Published: June 2015

Objective

There is often little consensus on the levels of trainees’ performances, given the varied expertise and experience of the assessors, different tasks to be assessed and dynamic circumstances. Consequently, assessors are considered to be a major source of measurement error in workplace assessment. The aim of this pilot study is to assess the inter-rater reliability and agreement of a hybrid framework for assessment of nonspecialist doctors in our Emergency Department.

Methods

A hybrid framework was used to evaluate two core competencies of medical knowledge and patient care of nonspecialist doctors in our Emergency Department. Pre and post scores of these doctors were obtained at the end of their posting.

Results

The inter-rater agreement and reliability was markedly higher for the group of nonspecialist doctors with previous Emergency Medicine experience, with fair-to-good reliability of the ratings among the assessors after application of the framework.

Conclusion

The use of our hybrid framework improved the inter-rater reliability and agreement in our Emergency Department for a specific group of learners who have had previous Emergency Medicine experience. To improve the reliability of ratings, faculty development has to address how observations and assessments should be synthesized into an overall rating.
Three-Dimensional Eyeball and Orbit Volume Modification After LeFort III Midface Distraction
Authors: Smektala Tomasz , Nysjö Johan , Thor Andreas , Homik Aleksandra , Sporniak-Tutak Katarzyna , Safranow Krzysztof , Dowgierd Krzysztof , Olszewski Raphael
Published: June 2015

The aim of our study was to evaluate orbital volume modification with LeFort III midface distraction in patients with craniosynostosis and its influence on eyeball volume and axial diameter modification. Orbital volume was assessed by the semiautomatic segmentation method based on deformable surface models and on 3-dimensional (3D) interaction with haptics. The eyeball volumes and diameters were automatically calculated after manual segmentation of computed tomographic scans with 3D slicer software. The mean, minimal, and maximal differences as well as the standard deviation and intraclass correlation coefficient (ICC) for intraobserver and interobserver measurements reliability were calculated. The Wilcoxon signed rank test was used to compare measured values before and after surgery. P < 0.05 was considered statistically significant. Intraobserver and interobserver ICC for haptic-aided semiautomatic orbital volume measurements were 0.98 and 0.99, respectively. The intraobserver and interobserver ICC values for manual segmentation of the eyeball volume were 0.87 and 0.86, respectively. The orbital volume increased significantly after surgery: 30.32% (mean, 5.96 mL) for the left orbit and 31.04% (mean, 6.31 mL) for the right orbit. The mean increase in eyeball volume was 12.3%. The mean increases in the eyeball axial dimensions were 7.3%, 9.3%, and 4.4% for the X-, Y-, and Z-axes, respectively. The Wilcoxon signed rank test showed that preoperative and postoperative eyeball volumes, as well as the diameters along the X- and Y-axes, were statistically significant. Midface distraction in patients with syndromic craniostenosis results in a significant increase (P < 0.05) in the orbit and eyeball volumes. The 2 methods (haptic-aided semiautomatic segmentation and manual 3D slicer segmentation) are reproducible techniques for orbit and eyeball volume measurements.
Crystal structure of 3-(hydroxymethyl)chromone
Authors: Ishikawa Yoshinobu
Published: June 2015

In the title compound, C10H8O3(systematic name 3-hydroxymethyl-4H-chromen-4-one), the fused-ring system is slightly puckered [dihedral angle between the rings = 3.84 (11)°]. The hydroxy O atom deviates from the heterocyclic ring by 1.422 (1) Å. In the crystal, inversion dimers linked by pairs of O—H...O hydrogen bonds generateR22(12) loops. The dimers are linked by aromatic π–π stacking [shortest centroid–centroid distance = 3.580 (3) Å], and C—H...O hydrogen bonds, generating a three-dimensional network.
Remuneration consultants’ advice and its effect on pay
Authors: Ndzi Ernestine
Published: June 2015

Purpose

– The purpose of this paper is to investigate the nature of advice that the remuneration consultants offer to the companies on executive pay. It explores how the advice offered affects the level of executive remuneration. Furthermore, it investigates whether the nature of advice offered forms part of the reasons why remuneration consultants have been criticised to be correlated with high executive pay.

Design/methodology/approach

– This paper analysis the data obtained from interviewing remuneration consultants from prominent consultancy firms that operate in the UK and the USA.

Findings

– This paper demonstrates that remuneration consultants’ advice on executive remuneration is not always objective. The nature of advice depends on whether the consultants have a balance of portfolio of companies (self-interest) or whether they have the courage to stand up to confrontations from the executives (fear of executives). This study shows that the purpose of using remuneration consultants in advising on executive remuneration is defeated. Also, the practice pushes up pay levels.

Research limitations/implications

– The research focused on large consultancy firm operating in the UK and/or the USA. Access to the participants was very difficult due to their busy schedules.

Practical implications

– This paper demonstrates the effect that lack of best practice on benchmarking is partly responsible for the high executive pay levels.

Social implications

– This paper will inform companies on the nature of advice that remuneration consultant’s offer and its effect on pay levels. Secondly, it will provide the shareholders with vital information they require to vote on remuneration policy in the annual general meeting.

Originality/value

– This paper demonstrates the effect that lack of best practice on benchmarking is partly responsible for the high executive pay levels. This paper will inform companies on the nature of advice that remuneration consultant’s offer and its effect on pay levels. Secondly, it will provide the shareholders with vital information they require to vote on remuneration policy in the annual general meeting. Lastly, it informs policymakers on the grey areas of practice that requires best practice.
What Place For The Region? Reflections on the Regional Question and the International Journal of Urban and Regional Research
Authors: Parker Simon , Harloe Michael
Published: June 2015

In our introduction to this Debates & Developments forum, ‘What place for the Region?’, we discuss why the founders of the International Journal of Urban and Regional Research (IJURR) regarded the regional question as having the same importance as the urban question, and how the region has remained a significant focus during the journal's subsequent development. We then explore some of the conceptual challenges in defining and investigating regions before considering some of the key developments in contemporary regional theory. Our introduction proceeds by highlighting the key insights of the contributions to the forum––essays by Edward Soja, Mariona Tomàs, Joe Beall, Susan Parnell and Chris Albertyn, and Jean‐Paul Addie and Roger Keil––before concluding with a reaffirmation of the importance of the region in IJURR's mission as a journal of critical urban and regional studies.
Dental caries, fluorosis, and oral health behavior of children from Herat, Afghanistan
Authors: Schwendicke Falk , Doost Ferhat , Hopfenmüller Werner , Meyer‐Lueckel Hendrik , Paris Sebastian
Published: June 2015

Objective

Decades of conflict, poverty, and dysfunctional public services have affected people's health in Afghanistan. To estimate treatment needs and guide health initiatives, epidemiologic data are required. Such data are currently unavailable for dental health. The present study assessed caries experience, fluorosis, and oral health behavior in children from Afghanistan.

Methods

We performed a two‐stage, school‐based cross‐sectional study in Herat province in Afghanistan. A total of 1059 children, 369 children aged 6–7, 300 aged 12, and 390 aged 15 years, were sampled. Caries was assessed according to ICDAS, and oral hygiene, dietary habits, and parental economic and educational status evaluated. Prevalence of fluorosis was assessed, and fluoride concentrations in drinking water and in used toothpastes were measured.

Results

Mean (SD) number of decayed, missing, or filled teeth was dmft = 4.88 (3.11), DMFT = 2.57 (2.16), and DMFT = 4.04 (3.03) in 6‐/7‐, 12‐, and 15‐year‐olds, respectively. The majority of lesions in 6‐year‐olds were cavitated, while 12‐ and 15‐year‐olds showed more non‐ or microcavitated lesions. Most lesions, especially in young children, were untreated. Mean (range) water fluoride concentration was 0.37 (0.19–0.67) ppm. Fluoride concentrations in evaluated toothpastes did not meet internationally recommended levels. The majority of children showed no or minimal fluorosis. Having fluorosis, infrequently consuming sweets, or having a father with high education was associated with low caries experience (dmfs/DMFS < 10), with OR (95% CI) being 0.64 (0.47/0.90), 0.65 (0.44–0.95), and 0.64 (0.47/0.90), respectively.

Conclusions

Examined Afghan children had high unmet dental treatment needs and caries experience. Sufficient access to restorative treatment and prevention measures is urgently required.
Influence of implant angulation and cyclic dislodging on the retentive force of two different overdenture attachments – an in vitro study
Authors: Srinivasan Murali , Schimmel Martin , Badoud Isabelle , Ammann Patrick , Herrmann François R. , Müller Frauke
Published: June 2015

Objective

This in vitro study evaluated the influence of implant angulations on the retentive behavior of two overdenture attachments during cyclic dislodging.

Methods

Models simulating a two‐implant overdenture situation were fabricated. They were divided into five groups based on their simulated implant angulations (Groups: 1 = 0°; 2 = 20°; 3 = 30°; 4 = 40°; and 5 = 60°; n = 90). Each group was further divided into two subgroups based on its attachment system (control attachment: LOCATOR®; test attachment: SFI‐Anchor®) except for group 5 which had no LOCATOR® group. All models underwent 10,000 insertion–removal cycles in a wet environment. Mean retentive forces were recorded. ANOVA and linear regression models were used for statistical analyses, and the level of significance was at P < 0.05.

Results

The ANOVA model revealed an effect of dislodging cycles for both attachments (P = 0.0070). The linear regression model with repeated measures revealed a significant effect of angulation within the LOCATOR® groups (0° vs. 20°: P < 0.0001; 0° vs. 30°: P < 0.0001; 0° vs. 40°: P < 0.0001), but was insignificant within the SFI‐Anchor® groups (0° vs. 20°: P = 0.544; 0° vs. 30°: P = 0.134; 0° vs. 40°: P = 0.254; 0° vs. 60°: P = 0.979). It further revealed a significant increase in the retentive force between the LOCATOR® and the SFI‐Anchor® (20°: P = 0.041; 30°: P < 0.0001; 40°: P < 0.0001), although there was no significant difference between the attachments at 0° (P = 0.623).

Conclusions

This study confirms that the retentive behavior of SFI‐Anchor® is not influenced by implant axial inclination even at angulations of up to 60°. The SFI‐Anchor® may therefore be particularly indicated for clinical situations with marked implant axial discrepancies.
Pharmacotherapy for alcohol addiction in a patient with alcoholic cirrhosis and massive upper gastrointestinal bleed: A case study
Authors: Young Samantha , Wood Evan , Ahamad Keith
Published: June 2015

Alcohol use causes a substantial burden of morbidity and mortality worldwide. The pharmacologic treatment of alcohol dependence has been increasingly studied and proven to improve outcomes in individuals with alcohol use disorder. However, the treatment of alcohol use disorder is often challenging in the context of patients with hepatic impairment as many medications to treat alcohol use disorder are hepatically metabolised or may cause liver toxicity in some instances. We present a case history of an individual with significant medical complications from alcohol use disorder and explore the dilemma faced in prescribing pharmacologic treatment of alcohol use disorder in patients with significant liver dysfunction. [Young S, Wood E, Ahamad K. Pharmacotherapy for alcohol addiction in a patient with alcoholic cirrhosis and massive upper gastrointestinal bleed: A case study. Drug Alcohol Rev 2016;35:236–239]
Familial Hemiplegic Migraine and Recurrent Episodes of Psychosis: A Case Report
Authors: LaBianca Sonja , Jensen Rigmor , van den Maagdenberg Arn M.J.M. , Baandrup Lone , Bendtsen Lars
Published: June 2015

Familial hemiplegic migraine (FHM) is a rare autosomal dominant form of migraine with motor aura. We present a case report of a father and son with very similar attacks of hemiplegic migraine and recurrent episodes of accompanying psychoses. Previously, such episodes led to hospitalization and extended clinical examinations, which further worsened the psychoses. Since the episodes were recognized as related to the hemiplegic migraine, a treatment strategy combining sleep and sedation was initiated and progression onto psychosis was almost completely avoided in both father and son. Genetic analyses found no causal gene mutation in the three known FHM genes, suggesting that the phenotype is caused by a yet unidentified mutation.
Influence of a glide path on apical extrusion of debris during canal preparation using single‐file systems in curved canals
Authors: Topçuoğlu H. S. , Düzgün S. , Akpek F. , Topçuoğlu G. , Aktı A.
Published: June 2015

Aim

To evaluate the effect of a glide path on the amount of apically extruded debris during canal preparation using single‐file systems in curved canals.

Methodology

Ninety extracted mandibular molar teeth were randomly assigned to six groups (n = 15 for each group) for canal instrumentation. Endodontic access cavities were prepared in each tooth. In three of the six groups, a glide path was not created whereas a glide path was created using PathFile instruments on the mesial canals of all teeth in the remaining three groups. The mesial canals of the teeth were then instrumented with the following single‐file instrument systems: WaveOne, Reciproc and OneShape. Debris extruded apically during instrumentation was collected into pre‐weighed Eppendorf tubes. The tubes were then stored in an incubator at 70 °C for 5 days. The weight of the dry extruded debris was established by subtracting the pre‐instrumentation and post‐instrumentation weight of the Eppendorf tubes for each group. The data obtained were analysed using one‐way analysis of variance (anova) and Tukey's post hoc tests.

Results

The OneShape file was associated with less debris extrusion than the Reciproc and WaveOne files when canal instrumentation was performed without a glide path (P < 0.05). However, no significant difference was found between the Reciproc and WaveOne files (P > 0.05). There was no significant difference amongst the OneShape, Reciproc and WaveOne files when a glide path was created before canal preparation in curved root canals (P > 0.05). All systems extruded significantly less debris in groups with a glide path than in groups without a glide path (P < 0.05).

Conclusions

All instruments were associated with apical extrusion of debris. Creating a glide path prior to canal instrumentation reduced the amount of apically extruded debris in curved canals.
Molecular and physiological roles of Pellino E3 ubiquitin ligases in immunity
Authors: Humphries Fiachra , Moynagh Paul N.
Published: June 2015

The sensing of foreign agents by the innate and adaptive immune system triggers complex signal transduction cascades that culminate in expression of gene patterns that facilitate host protection from the invading agent. Post‐translational modification of intracellular signaling proteins in these pathways is a key regulatory mechanism with ubiquitination being one of the important processes that controls levels and activities of signaling molecules. E3 ubiquitin ligases are the determining enzymes in dictating the ubiquitination status of individual proteins. Among these hundred E3 ubiquitin ligases are a family of Pellino proteins that are emerging to be important players in immunity and beyond. Herein, we review the roles of the Pellino E3 ubiquitin ligases in innate and adaptive immunity. We discuss their early discovery and characterization and how this has been aided by the highly conserved nature of innate immune signaling across evolution. We describe the molecular roles of Pellino proteins in immune signaling with particular emphasis on their involvement in pathogen recognition receptor (PRR) signaling. The growing appreciation of the importance of Pellino proteins in a wide range of immune‐mediated diseases are also evaluated.
Structural Investigation of Monoclinic‐Rhombohedral Phase Transition in Na3Zr2Si2PO12 and Doped NASICON
Authors: Jolley Adam G. , Taylor Daniel D. , Schreiber Nathaniel J. , Wachsman Eric D.
Published: June 2015

Aliovalent doping of the zirconium site in Na3Zr2Si2PO12 (NASICON) was performed with a range of +3 (Al, Y, Fe) and +2 (Co, Ni, Zn) valent cations. The monoclinic‐rhombohedral phase transition was analyzed with high‐temperature in situ X‐ray diffraction, and differential scanning calorimetry (DSC). From the lattice parameters extracted at room temperature up to 300°C it was determined that the high‐temperature rhombohedral phase distorts to the low‐temperature monoclinic phase through a shear deformation of the unit cell. DSC confirmed the phase transition and demonstrated that the phase transition temperature was lowered by doping the NASICON structure. Furthermore, the distortion of the lattice was less severe for all doped samples. Ultimately aliovalent substitution for zirconium stabilized the higher symmetry rhombohedral phase of NASICON, with yttrium doping providing the lowest phase transition temperature and the smallest distortion of the lattice through the phase change.
Trophic behaviour of juvenile reef fishes inhabiting interlinked mangrove–seagrass habitats in offshore mangrove islets
Authors: Vaslet A. , Phillips D. L. , France C. A. M. , Feller I. C. , Baldwin C. C.
Published: June 2015

Stable isotope (δ13C and δ15N) and gut content analyses were used to investigate size‐related feeding habits of four reef fishes (the beaugregory Stegastes leucostictus, the french grunt Haemulon flavolineatum, the schoolmaster snapper Lutjanus apodus and the yellowtail snapper Ocyurus chrysurus) inhabiting an offshore (non‐estuarine) mangrove islet off Belize, Central America. Comparisons of isotopic niche space and Schoener diet similarity index suggested a low to moderate degree of niche overlap between fish size groups. The δ13C gradient between mangrove and seagrass prey as well as results of Bayesian mixing models revealed that sampled fishes relied mostly on seagrass prey items. Only small and large juveniles of the carnivorous species L. apodus derived a part of their diet from mangroves by targeting mangrove‐associated Grapsidae crabs and fish prey, respectively. Isotopic niche shifts were particularly obvious for carnivorous fishes that ingested larger prey items (Xanthidae crabs and fishes) during their ontogeny. The utilization of mangrove food resources is less than expected and depends on the ecology and life history of the fish species considered. This research highlights that mangrove‐derived carbon contributed relatively little to the diets of four fish taxa from an offshore mangrove islet.
Thermotolerance of Rifampicin‐Resistant Escherichia coli O157:H7 Derivatives and Their Parental Strains in a Broth System
Authors: Ko Kyung Yuk , Geornaras Ifigenia , Byelashov Oleksandr A. , Paik Hyun‐Dong , Kim Kee‐Tae , Sofos John N.
Published: June 2015

Rifampicin‐resistant (RifR) strains have often been used in studies of Escherichia coli O157:H7 to assure more specific recovery. The present study compared the heat inactivation kinetics of rifampicin‐resistant variants of pathogenic and nonpathogenic E. coli O157 strains with those of the wild‐type parental strains. Spontaneous RifR derivatives of 11 pathogenic and six nonpathogenic E. coli O157 strains were selected. Stationary‐phase cells of each strain in sterile tryptic soy broth were heated at 60C for 0, 30, 60, 90, 120, 150, 180 or 240 s, and aliquots were plated on tryptic soy agar supplemented with 0.1% pyruvate + 100 μg/mL rifampicin. D values of three pathogenic and two nonpathogenic RifR E. coli O157 strains were 35–70% lower (P < 0.05) than those of their wild‐type counterparts. However, the heat resistance of most of the RifR E. coli O157:H7 strains (12 strains) was similar (P ≥ 0.05) to that of their parental counterparts. Therefore, the findings of this study demonstrated that the majority of the rifampicin‐resistant E. coli O157:H7 variants that were evaluated to assure more reliable recovery in microbial inactivation studies are suitable for use in various heat challenge studies.

Practical Applications

More reliable media are needed for the isolation or recovery of E. coli O157:H7 in inoculated challenge studies. Prior to use of rifampicin‐resistant E. coli O157:H7 strains in heat challenge studies, it is important that their thermal inactivation kinetics be compared with those of their wild‐type parental strains. The results of this study showed that the thermotolerance at 60C of the majority of the tested rifampicin‐resistant E. coli O157:H7 variants was not different than that of the corresponding wild‐type strains. These rifampicin‐resistant strains can, therefore, be used in heat challenge studies and can be recovered with non‐selective culture media supplemented with rifampicin.
Propensity score weighting: an application to anEarlyHeadStart dental study
Authors: Burgette Jacqueline M. , Preisser John S. , Rozier R. Gary
Published: June 2015

Objectives

Nonrandomized group assignment in intervention studies can lead to imbalances in preintervention covariates and biased effect estimates. We use propensity score estimation to account for such imbalances in anEarlyHeadStart (EHS) dataset with rich pretreatment information. We compare propensity score results using standard logistic regression models (LRMs) versus generalized boosted models (GBMs).

Methods

We estimated propensity scores using 47 socio‐demographic characteristics andEHSenrollment criteria obtained by parent interviews from a state‐wide sample of 637EHSand 930 Medicaid‐matched control children.LRMs andGBMs were used to estimate propensity scores related toEHSenrollment. Performance of both approaches was evaluated via a) measures of balance of pretreatment covariate distributions between treated and control subjects, and b) stability of propensity score weights measured by the effective sample size.

Results

Distributions of all variables were balanced forEHSand non‐EHSgroups using propensity score weights calculated withLRMandGBM. Compared withLRM,GBMresulted in better balance between treated and propensity score‐weighted control distributions. The effective sample size of the controls decreased from 930 subjects to 507 withGBMand to 335 withLRM.

Conclusion

Although propensity scores derived fromGBMandLRMboth effectively balanced observed preintervention covariates,GBMresulted in better covariate balance compared withLRM.GBMalso resulted in a larger effective sample size of the control group compared withLRM. Propensity score weighting usingGBMis an effective statistical method to reduce confounding due to imbalanced distributions of measured preintervention covariates in thisEHSintervention study.
LIME silicates in amoeboid olivine aggregates in carbonaceous chondrites: Indicator of nebular and asteroidal processes
Authors: Komatsu Mutsumi , Fagan Timothy J. , Mikouchi Takashi , Petaev Michail I. , Zolensky Michael E.
Published: June 2015

MnO/FeO ratios in olivine from amoeboid olivine aggregates (AOAs) reflect conditions of nebular condensation and can be used in concert with matrix textures to compare metamorphic conditions in carbonaceous chondrites. LIME (low‐iron, Mn‐enriched) olivine was identified in AOAs from Y‐81020 (CO3.05), Kaba (CV~3.1), and in Y‐86009 (CV3), Y‐86751 (CV3), NWA 1152 (CR/CV3), but was not identified in AOAs from Efremovka (CV3.1–3.4) or Allende (CV>3.6). According to thermodynamic models of nebular condensation, LIME olivine is stable at lower temperatures than Mn‐poor olivine and at low oxygen fugacities (dust enrichment <10× solar). Although this set of samples does not represent a single metamorphic sequence, the higher subtypes tend to have AOA olivine with lower Mn/Fe, suggesting that Mn/Fe decreases during parent body metamorphism. Y‐81020 has the lowest subtype and most forsteritic AOA olivine (Fo>95) in our study, whereas Efremovka AOAs are slightly Fe‐rich (Fo>92). AOA olivines from Kaba are mostly forsteritic, but rare Fe‐rich olivine precipitated from an aqueous fluid. A combination of precipitation of Fe‐rich olivine and diffusion of Fe into primary olivine grains resulted in iron‐rich compositions (Fo97–59) in Allende AOAs. Variations from fine‐grained, nonporous matrix toward higher porosity and coarser lath‐like matrix olivine can be divided into six stages represented by (1) Y‐81020, Efremovka, NWA 1152; (2) Y‐86751 lithology B; (3) Y‐86009; (4) Kaba; (5) Y‐86751 lithology A; (6) Allende. These stages are inferred to represent general degree of metamorphism, although the specific roles of thermally driven grain growth and diffusion versus aqueous dissolution and precipitation remain uncertain.
Expectations and experiences of older people and their carers in relation to emergency department arrival and care: A qualitative study in Australia
Authors: Stein‐Parbury Jane , Gallagher Robyn , Fry Margaret , Chenoweth Lynn , Gallagher Patrick
Published: June 2015

Although older people frequently present to the emergency department (ED), little is known about their experiences in this setting, despite increasing attendance rates reported in this population internationally. This study explores the experiences of older people and their carers leading to and during ED care in a metropolitan university hospital in Sydney, Australia. The study forms part of a larger prospective exploratory study on this topic. Individual in‐depth interviews were conducted with 10 people over 65 years of age who had a chronic illness and their carers one month after they presented to the ED. Interviews were transcribed verbatim and analyzed using general interpretive methods. The results revealed that the participants presented to the ED as a result of escalating symptoms and on their general practitioner's advice. Participants felt uninformed about ED procedures, therefore, families/carers felt the need to advocate for information and basic services. Participants were grateful for the care received and mindful of the busy environment. To meet the expectations of older people, nurses need to provide timely information and advise carers how they can assist.
Interruptions and medication administration in critical care
Authors: Bower Rachel , Jackson Christine , Manning Joseph C
Published: June 2015

Background

Medication administration has inherent risks, with errors having enormous impact on the quality and efficiency of patient care, particularly in relation to experience, outcomes and safety. Nurses are pivotal to the medication administration process and therefore must demonstrate safe and reliable practice. However, interruptions can lead to mistakes and omissions.

Aim

To critique and synthesize the existing literature relating to the impact that interruptions have during medication administration within the paediatric critical care (PCC) setting.

Search strategy

Key terms identified from background literature were used to search three electronic databases (Medline, CINHAL and BNI). Selected sources were critically appraised using the Critical Appraisal Skills Programme (CASP) tool.

Findings

There is confusion within the literature concerning the definition of interruption. Moreover, an assumption that all interruptions have a negative impact on patient safety exists. The literature identifies the multi‐dimensional nature of interruptions and their impact on medication administration and patient safety. The cumulative effect of interruptions depends on what type of task is being completed, when it occurs, what the interruption is and which method of handling is utilized. A conceptual schema has been developed in order to explicate the themes and concepts that emerged.

Conclusions

This review summarizes debates within the international arena concerning the impact of interruptions on medication administration. However, conclusions drawn appear applicable in relation to practice, education and future research to other critical care settings.

Relevance to clinical practice

Findings show that no single strategy is likely to improve the negative effect of interruptions without focus on patient safety. Practice education to improve team building interactions is required that equips nurses with the skills in managing interruptions and delegating high priority secondary tasks.
The Big Five in Context: Personality, Diversity and Attitudes toward Equal Opportunities for Immigrants in Switzerland
Authors: Ackermann Kathrin , Ackermann Maya
Published: June 2015

The paper analyzes the link between personality traits and attitudes of Swiss citizens toward equal opportunities for immigrants. In particular, we examine the extent to which this relationship is moderated by the socio‐structural context. We test the assumption that the direct links between personality traits and attitudes toward equal opportunities are strengthened by perceived ethnic diversity. Based on our empirical analyses, we are able to replicate central findings of the research on personality traits and attitudes toward immigrants for the Swiss context. While openness toward experience and agreeableness are positively related to a preference for equal opportunities, conscientiousness is negatively linked to these attitudes. Furthermore, our results reveal that the link between conscientiousness and attitudes toward equal opportunities is significantly moderated by the perceived share of foreigners in the neighborhood. This finding is especially relevant for future research on the effects of personality traits.