bluuebunny/crossref_metadata_2025 huggingface dataset:
Low threshold tunable spaser based on multipolar Fano resonances in disk–ring plasmonic nanostructures
Authors: Zheng Chunjie , Jia Tianqing , Zhao Hua , Zhang Shian , Feng Donghai , Sun Zhenrong
Published: November 2015

In this paper, we study theoretically spasers based on multipolar Fano resonances in disk-ring nanostructures covered with a silica layer doped with Yb3+:Er3+ used as the gain material. The electric field amplitudes at the quadrupolar mode (lasing wavelength) and the octupolar mode (pumping wavelength) are simultaneously enhanced by tens of times. Moreover, the spaser operates in a dark mode, which can reduce the radiation loss and enhance the confinement effectively. These factors work together to decrease greatly the critical gain coefficient and threshold. By adjusting the elliptic partial degrees of the nano-ring, the spasers can be tuned in the range of 1550 to 1650 nm, while the pumping light remains at the 980 nm absorption band of Yb3+ ions. Moreover, the spasers at three Fano resonance wavelengths of the disk-ring nanostructures appear in sequence with increasing the gain coefficient. The effects of the extinction coefficient on the electric field amplitudes of the pump light are also studied.
Structural transitions in different monolayers of cobalt phthalocyanine film grown on Bi(1 1 1)
Authors: Tao Min-Long , Tu Yu-Bing , Sun Kai , Zhang Yao , Zhang Xin , Li Zhao-Bing , Hao Shao-Jie , Xiao Hua-Fang , Ye Juan , Wang Jun-Zhong
Published: November 2015

The structural evolution of cobalt phthalocyanine (CoPc) thin films grown on a Bi(1 1 1) surface from the sub-monolayer to the third layer has been investigated with low-temperature scanning tunneling microscopy (STM). Two crucial transitions have been identified during the film epitaxial growth: one is the structural transition from zigzag chains to linear dimerized chains in the monolayer regime; the other is the molecular orientational transition from a flat-lying to a standing-up configuration in the multilayer regime. These results are helpful in understanding the growth mechanism of transition-metal phthalocyanine films on semi-metallic surfaces.
Neutronic design studies of a conceptual DCLL fusion reactor for a DEMO and a commercial power plant
Authors: Palermo I. , Veredas G. , Gómez-Ros J.M. , Sanz J. , Ibarra A.
Published: November 2015

Neutronic analyses or, more widely, nuclear analyses have been performed for the development of a dual-coolant He/LiPb (DCLL) conceptual design reactor. A detailed three-dimensional (3D) model has been examined and optimized. The design is based on the plasma parameters and functional materials of the power plant conceptual studies (PPCS) model C. The initial radial-build for the detailed model has been determined according to the dimensions established in a previous work on an equivalent simplified homogenized reactor model. For optimization purposes, the initial specifications established over the simplified model have been refined on the detailed 3D design, modifying material and dimension of breeding blanket, shield and vacuum vessel in order to fulfil the priority requirements of a fusion reactor in terms of the fundamental neutronic responses. Tritium breeding ratio, energy multiplication factor, radiation limits in the TF coils, helium production and displacements per atom (dpa) have been calculated in order to demonstrate the functionality and viability of the reactor design in guaranteeing tritium self-sufficiency, power efficiency, plasma confinement, and re-weldability and structural integrity of the components. The paper describes the neutronic design improvements of the DCLL reactor, obtaining results for both DEMO and power plant operational scenarios.
A horse's eye view: size and shape discrimination compared with other mammals
Authors: Tomonaga Masaki , Kumazaki Kiyonori , Camus Florine , Nicod Sophie , Pereira Carlos , Matsuzawa Tetsuro
Published: November 2015

Mammals have adapted to a variety of natural environments from underwater to aerial and these different adaptations have affected their specific perceptive and cognitive abilities. This study used a computer-controlled touchscreen system to examine the visual discrimination abilities of horses, particularly regarding size and shape, and compared the results with those from chimpanzee, human and dolphin studies. Horses were able to discriminate a difference of 14% in circle size but showed worse discrimination thresholds than chimpanzees and humans; these differences cannot be explained by visual acuity. Furthermore, the present findings indicate that all species use length cues rather than area cues to discriminate size. In terms of shape discrimination, horses exhibited perceptual similarities among shapes with curvatures, vertical/horizontal lines and diagonal lines, and the relative contributions of each feature to perceptual similarity in horses differed from those for chimpanzees, humans and dolphins. Horses pay more attention to local components than to global shapes.
Faces and fitness: attractive evolutionary relationship or ugly hypothesis?
Authors: Smoliga James M. , Zavorsky Gerald S.
Published: November 2015

In recent years, various studies have attempted to understand human evolution by examining relationships between athletic performance or physical fitness and facial attractiveness. Over a wide range of five homogeneous groups (
n
= 327), there is an approximate 3% shared variance between facial attractiveness and athletic performance or physical fitness (95% CI = 0.5–8%,
p
= 0.002). Further, studies relating human performance and attractiveness often have major methodological limitations that limit their generalizability. Thus, despite statistical significance, the association between facial attractiveness and human performance has questionable biological importance. Here, we present a critique of these studies and provide recommendations to improve the quality of future research in this realm.
The organization of biological sequences into constrained and unconstrained parts determines fundamental properties of genotype–phenotype maps
Authors: Greenbury S. F. , Ahnert S. E.
Published: November 2015

Biological information is stored in DNA, RNA and protein sequences, which can be understood as genotypes that are translated into phenotypes. The properties of genotype–phenotype (GP) maps have been studied in great detail for RNA secondary structure. These include a highly biased distribution of genotypes per phenotype, negative correlation of genotypic robustness and evolvability, positive correlation of phenotypic robustness and evolvability, shape-space covering, and a roughly logarithmic scaling of phenotypic robustness with phenotypic frequency. More recently similar properties have been discovered in other GP maps, suggesting that they may be fundamental to biological GP maps, in general, rather than specific to the RNA secondary structure map. Here we propose that the above properties arise from the fundamental organization of biological information into ‘constrained' and ‘unconstrained' sequences, in the broadest possible sense. As ‘constrained' we describe sequences that affect the phenotype more immediately, and are therefore more sensitive to mutations, such as, e.g. protein-coding DNA or the stems in RNA secondary structure. ‘Unconstrained' sequences, on the other hand, can mutate more freely without affecting the phenotype, such as, e.g. intronic or intergenic DNA or the loops in RNA secondary structure. To test our hypothesis we consider a highly simplified GP map that has genotypes with ‘coding' and ‘non-coding' parts. We term this the Fibonacci GP map, as it is equivalent to the Fibonacci code in information theory. Despite its simplicity the Fibonacci GP map exhibits all the above properties of much more complex and biologically realistic GP maps. These properties are therefore likely to be fundamental to many biological GP maps.
Searching for motifs in the behaviour of larval
Drosophila melanogaster
and
Caenorhabditis elegans
reveals continuity between behavioural states
Authors: Szigeti Balázs , Deogade Ajinkya , Webb Barbara
Published: November 2015

We present a novel method for the unsupervised discovery of behavioural motifs in larval
Drosophila melanogaster
and
Caenorhabditis elegans
. A motif is defined as a particular sequence of postures that recurs frequently. The animal's changing posture is represented by an eigenshape time series, and we look for motifs in this time series. To find motifs, the eigenshape time series is segmented, and the segments clustered using spline regression. Unlike previous approaches, our method can classify sequences of unequal duration as the same motif. The behavioural motifs are used as the basis of a probabilistic behavioural annotator, the eigenshape annotator (ESA). Probabilistic annotation avoids rigid threshold values and allows classification uncertainty to be quantified. We apply eigenshape annotation to both larval
Drosophila
and
C. elegans
and produce a good match to hand annotation of behavioural states. However, we find many behavioural events cannot be unambiguously classified. By comparing the results with ESA of an artificial agent's behaviour, we argue that the ambiguity is due to greater continuity between behavioural states than is generally assumed for these organisms.
Satellite tracking reveals novel migratory patterns and the importance of seamounts for endangered South Pacific humpback whales
Authors: Garrigue Claire , Clapham Phillip J. , Geyer Ygor , Kennedy Amy S. , Zerbini Alexandre N.
Published: November 2015

The humpback whale population of New Caledonia appears to display a novel migratory pattern characterized by multiple directions, long migratory paths and frequent pauses over seamounts and other shallow geographical features. Using satellite-monitored radio tags, we tracked 34 whales for between 5 and 110 days, travelling between 270 and 8540 km on their southward migration from a breeding ground in southern New Caledonia. Mean migration speed was 3.53±2.22 km h−1, while movements within the breeding ground averaged 2.01±1.63 km h−1. The tag data demonstrate that seamounts play an important role as offshore habitats for this species. Whales displayed an intensive use of oceanic seamounts both in the breeding season and on migration. Seamounts probably serve multiple and important roles as breeding locations, resting areas, navigational landmarks or even supplemental feeding grounds for this species, which can be viewed as a transient component of the seamount communities. Satellite telemetry suggests that seamounts represent an overlooked cryptic habitat for the species. The frequent use by humpback whales of such remote locations has important implications for conservation and management.
Fast and accurate construction of confidence intervals for heritability
Authors: Schweiger Regev , Kaufman Shachar , Laaksonen Reijo , Kleber Marcus E , März Winfried , Eskin Eleazar , Rosset Saharon , Halperin Eran
Published: November 2015

Estimation of heritability is fundamental in genetic studies. In recent years, heritability estimation using linear mixed models (LMMs) has gained popularity, because these estimates can be obtained from unrelated individuals collected in genome wide association studies. Typically, heritability estimation under LMMs uses either the maximum likelihood (ML) or the restricted maximum likelihood (REML) approach. Existing methods for the construction of confidence intervals and estimators of standard errors for both ML and REML rely on asymptotic properties. However, these assumptions are often violated due to the bounded parameter space, statistical dependencies, and limited sample size, leading to biased estimates, and inflated or deflated confidence intervals. Here, we show that often the probability that the genetic component is estimated as zero is high even when the true heritability is bounded away from zero, emphasizing the need for accurate confidence intervals. We further show that the estimation of confidence intervals by state-of-the-art methods is highly inaccurate, especially when the true heritability is either relatively low or relatively high. Such biases are present, for example, in estimates of heritability of gene expression in the GTEx study, and of lipid profiles in the LURIC study. We propose a computationally efficient method, AccurateLMM-Based confidenceIntervals (ALBI), for the estimation of the distribution of the heritability estimator, and for the construction of accurate confidence intervals. Our method can be used as an add-on to existing methods for heritability and variance components estimation, such as GCTA, FaST-LMM, GEMMA, or EMMA. ALBI is available athttp://www.cs.tau.ac.il/~heran/cozygene/software/albi.html.
A comparison of one-rate and two-rate inference frameworks for site-specificdN/dSestimation
Authors: Spielman Stephanie J. , Wan Suyang , Wilke Claus O.
Published: November 2015

Two broad paradigms exist for inferringdN/dS, the ratio of nonsynonymous to synonymous substitution rates, from coding sequences: i) a one-rate approach, wheredN/dSis represented with a single parameter, or ii) a two-rate approach, where dN and dS are estimated separately. The performances of these two approaches have been well-studied in the specific context of proper model specification, i.e. when the inference model matches the simulation model. By contrast, the relative performances of one-rate vs. two-rate parameterizations when applied to data generated according to a different mechanism remains unclear. Here, we compare the relative merits of one-rate and two-rate approaches in the specific context of model misspecification by simulating alignments with mutation-selection models rather than withdN/dS-based models. We find that one-rate frameworks generally infer more accuratedN/dSpoint estimates, even when dS varies among sites. In other words, modelingdSvariation may substantially reduce accuracy ofdN/dSpoint estimates. These results appear to depend on the selective constraint operating at a given site. In particular, for sites under strong purifying selection (dN/dS<~0.3), one-rate and two-rate models show comparable performances. However, one-rate models significantly outperform two-rate models for sites under moderate-to-weak purifying selection. We attribute this distinction to the fact that, for these more quickly evolving sites, a given substitution is more likely to be nonsynonymous than synonymous. The data will therefore be relatively enriched for nonsynonymous changes, and modeling dS contributes excessive noise todN/dSestimates. We additionally find that high levels of divergence among sequences, rather than the number of sequences in the alignment, are more critical for obtaining precise point estimates.
Sent packing: protein engineering generates a new crystal form ofPseudomonas aeruginosaDsbA1 with increased catalytic surface accessibility
Authors: McMahon Roisin M. , Coinçon Mathieu , Tay Stephanie , Heras Begoña , Morton Craig J. , Scanlon Martin J. , Martin Jennifer L.
Published: November 2015

Pseudomonas aeruginosais an opportunistic human pathogen for which new antimicrobial drug options are urgently sought.P. aeruginosadisulfide-bond protein A1 (PaDsbA1) plays a pivotal role in catalyzing the oxidative folding of multiple virulence proteins and as such holds great promise as a drug target. As part of a fragment-based lead discovery approach to PaDsbA1 inhibitor development, the identification of a crystal form of PaDsbA1 that was more suitable for fragment-soaking experiments was sought. A previously identified crystallization condition for this protein was unsuitable, as in this crystal form of PaDsbA1 the active-site surface loops are engaged in the crystal packing, occluding access to the target site. A single residue involved in crystal-packing interactions was substituted with an amino acid commonly found at this position in closely related enzymes, and this variant was successfully used to generate a new crystal form of PaDsbA1 in which the active-site surface is more accessible for soaking experiments. The PaDsbA1 variant displays identical redox character andin vitroactivity to wild-type PaDsbA1 and is structurally highly similar. Two crystal structures of the PaDsbA1 variant were determined in complex with small molecules bound to the protein active site. These small molecules (MES, glycerol and ethylene glycol) were derived from the crystallization or cryoprotectant solutions and provide a proof of principle that the reported crystal form will be amenable to co-crystallization and soaking with small molecules designed to target the protein active-site surface.
Unravelling the shape and structural assembly of the photosynthetic GAPDH–CP12–PRK complex fromArabidopsis thalianaby small-angle X-ray scattering analysis
Authors: Del Giudice Alessandra , Pavel Nicolae Viorel , Galantini Luciano , Falini Giuseppe , Trost Paolo , Fermani Simona , Sparla Francesca
Published: November 2015

Oxygenic photosynthetic organisms produce sugars through the Calvin–Benson cycle, a metabolism that is tightly linked to the light reactions of photosynthesis and is regulated by different mechanisms, including the formation of protein complexes. Two enzymes of the cycle, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK), form a supramolecular complex with the regulatory protein CP12 with the formula (GAPDH–CP122–PRK)2, in which both enzyme activities are transiently inhibited during the night. Small-angle X-ray scattering analysis performed on both the GAPDH–CP12–PRK complex and its components, GAPDH–CP12 and PRK, fromArabidopsis thalianashowed that (i) PRK has an elongated, bent and screwed shape, (ii) the oxidized N-terminal region of CP12 that is not embedded in the GAPDH–CP12 complex prefers a compact conformation and (iii) the interaction of PRK with the N-terminal region of CP12 favours the approach of two GAPDH tetramers. The interaction between the GAPDH tetramers may contribute to the overall stabilization of the GAPDH–CP12–PRK complex, the structure of which is presented here for the first time.
Crystal structure and kinetic studies of a tetrameric type II β-carbonic anhydrase from the pathogenic bacteriumVibrio cholerae
Authors: Ferraroni Marta , Del Prete Sonia , Vullo Daniela , Capasso Clemente , Supuran Claudiu T.
Published: November 2015

Carbonic anhydrase (CA) is a zinc enzyme that catalyzes the reversible conversion of carbon dioxide to bicarbonate (hydrogen carbonate) and a proton. CAs have been extensively investigated owing to their involvement in numerous physiological and pathological processes. Currently, CA inhibitors are widely used as antiglaucoma, anticancer and anti-obesity drugs and for the treatment of neurological disorders. Recently, the potential use of CA inhibitors to fight infections caused by protozoa, fungi and bacteria has emerged as a new research direction. In this article, the cloning and kinetic characterization of the β-CA fromVibrio cholerae(VchCAβ) are reported. The X-ray crystal structure of this new enzyme was solved at 1.9 Å resolution from a crystal that was perfectly merohedrally twinned, revealing a tetrameric type II β-CA with a closed active site in which the zinc is tetrahedrally coordinated to Cys42, Asp44, His98 and Cys101. The substrate bicarbonate was found bound in a noncatalytic binding pocket close to the zinc ion, as reported for a few other β-CAs, such as those fromEscherichia coliandHaemophilus influenzae. At pH 8.3, the enzyme showed a significant catalytic activity for the physiological reaction of the hydration of CO2to bicarbonate and protons, with the following kinetic parameters: akcatof 3.34 × 105 s−1and akcat/Kmof 4.1 × 107 M−1 s−1. The new enzyme, on the other hand, was poorly inhibited by acetazolamide (Kiof 4.5 µM). As this bacterial pathogen encodes at least three CAs, an α-CA, a β-CA and a γ-CA, these enzymes probably play an important role in the life cycle and pathogenicity ofVibrio, and it cannot be excluded that interference with their activity may be exploited therapeutically to obtain antibiotics with a different mechanism of action.
Small-angle scattering determination of the shape and localization of human cytochrome P450 embedded in a phospholipid nanodisc environment
Authors: Skar-Gislinge Nicholas , Kynde Søren A. R. , Denisov Ilia G. , Ye Xin , Lenov Ivan , Sligar Stephen G. , Arleth Lise
Published: November 2015

Membrane proteins reconstituted into phospholipid nanodiscs comprise a soluble entity accessible to solution small-angle X-ray scattering (SAXS) studies. It is demonstrated that using SAXS data it is possible to determine both the shape and localization of the membrane protein cytochrome P450 3A4 (CYP3A4) while it is embedded in the phospholipid bilayer of a nanodisc. In order to accomplish this, a hybrid approach to analysis of small-angle scattering data was developed which combines an analytical approach to describe the multi-contrast nanodisc with a free-form bead-model description of the embedded protein. The protein shape is then reconstructedab initioto optimally fit the data. The result of using this approach is compared with the result obtained using a rigid-body description of the CYP3A4-in-nanodisc system. Here, the CYP3A4 structure relies on detailed information from crystallographic and molecular-dynamics studies of CYP3A4. Both modelling approaches arrive at very similar solutions in which the α-helical anchor of the CYP3A4 systematically stays close to the edge of the nanodisc and with the large catalytic domain leaning over the outer edge of the nanodisc. The obtained distance between the globular domains of CYP3A4 is consistent with previously published theoretical calculations.
X-ray-induced catalytic active-site reduction of a multicopper oxidase: structural insights into the proton-relay mechanism and O2-reduction states
Authors: Serrano-Posada Hugo , Centeno-Leija Sara , Rojas-Trejo Sonia Patricia , Rodríguez-Almazán Claudia , Stojanoff Vivian , Rudiño-Piñera Enrique
Published: November 2015

During X-ray data collection from a multicopper oxidase (MCO) crystal, electrons and protons are mainly released into the system by the radiolysis of water molecules, leading to the X-ray-induced reduction of O2to 2H2O at the trinuclear copper cluster (TNC) of the enzyme. In this work, 12 crystallographic structures ofThermus thermophilusHB27 multicopper oxidase (Tth-MCO) in holo, apo and Hg-bound forms and with different X-ray absorbed doses have been determined. In holoTth-MCO structures with four Cu atoms, the proton-donor residue Glu451 involved in O2reduction was found in a double conformation: Glu451a (∼7 Å from the TNC) and Glu451b (∼4.5 Å from the TNC). A positive peak of electron density above 3.5σ in anFo−Fcmap for Glu451a O∊2indicates the presence of a carboxyl functional group at the side chain, while its significant absence in Glu451b strongly suggests a carboxylate functional group. In contrast, for apoTth-MCO and in Hg-bound structures neither the positive peak nor double conformations were observed. Together, these observations provide the first structural evidence for a proton-relay mechanism in the MCO family and also support previous studies indicating that Asp106 does not provide protons for this mechanism. In addition, eight composite structures (Tth-MCO-C1–8) with different X-ray-absorbed doses allowed the observation of different O2-reduction states, and a total depletion of T2Cu at doses higher than 0.2 MGy showed the high susceptibility of this Cu atom to radiation damage, highlighting the importance of taking radiation effects into account in biochemical interpretations of an MCO structure.
Octameric structure ofStaphylococcus aureusenolase in complex with phosphoenolpyruvate
Authors: Wu Yunfei , Wang Chengliang , Lin Shenglong , Wu Minhao , Han Lu , Tian Changlin , Zhang Xuan , Zang Jianye
Published: November 2015

Staphylococcus aureusis a Gram-positive bacterium with strong pathogenicity that causes a wide range of infections and diseases. Enolase is an evolutionarily conserved enzyme that plays a key role in energy production through glycolysis. Additionally, enolase is located on the surface ofS. aureusand is involved in processes leading to infection. Here, crystal structures ofSa_enolase with and without bound phosphoenolpyruvate (PEP) are presented at 1.6 and 2.45 Å resolution, respectively. The structure reveals an octameric arrangement; however, both dimeric and octameric conformations were observed in solution. Furthermore, enzyme-activity assays show that only the octameric variant is catalytically active. Biochemical and structural studies indicate that the octameric form ofSa_enolase is enzymatically activein vitroand likely alsoin vivo, while the dimeric form is catalytically inactive and may be involved in other biological processes.
Monetary compensation, workforce-oriented corporate social responsibility, and firm performance
Authors: Feng Mingming , Wang Xiaodan  "Abby" , Saini Jagjit S.
Published: November 2015

Purpose

– Prior literature has established the theoretical and statistical linkages between monetary compensation and firm performance, yet little is known about how the association between monetary compensation and firm performance is moderated by companies’ engagement in corporate social responsibility (CSR) activities. Further, compared to executive compensation, non-executive compensation remains an underexplored topic. The purpose of this paper is to investigate how workforce-oriented CSR moderates: first, the association between non-executive compensation and firm performance; and second, the association between executive compensation and firm performance.

Design/methodology/approach

– Using a sample of 181 from the largest 3,000 US companies for the years 1991-2011, the authors investigate how workforce-oriented CSR moderates the association between compensation and firm performance. Compensation is examined at two levels – non-executive versus executive compensation. The workforce-oriented CSR score is constructed as total strengths minus total concerns in Kinder, Lydenberg, and Domini’s employee relations dimension.

Findings

– The authors find an improvement in firm performance with increases in both non-executive and executive compensation. Further, workforce-oriented CSR positively moderates the association between non-executive compensation and firm performance, and negatively moderates the association between executive compensation and firm performance.

Research limitations/implications

– This study adds to the literature of the compensation-performance linkage by including both non-executive and executive compensation as important determinants of firm performance and incorporating workforce-oriented CSR as a moderator on the compensation-performance linkage. It also provides new angles for CSR scholars.

Practical implications

– This study helps managers understand the importance of fulfilling employees’ social emotional needs and the potential of workforce-oriented CSR in shaping employees’ perceived distributive justice. The findings also help managers make critical decisions regarding the allocation of limited corporate resources and prioritization of investment options. In addition, the findings are also useful to boards of directors and human resources managers who are in charge of hiring executives, building top management teams, and deciding executive compensation.

Originality/value

– This study helps advance our understanding of the compensation-performance linkage. The results suggest that the relationship between compensation and financial performance is contingent on other organizational factors. In addition, the findings provide practical implications on how CSR engagement moderates the association between non-executive compensation and firm performance differently than the association between executive compensation and firm performance and how to allocate corporate resources and prioritize strategic options effectively.
One educator, four perspectives
Authors: Stearns-Pfeiffer Amanda
Published: November 2015

Purpose

– The author of this paper aims to reflect on the past 14 years of English education in the USA and the resulting effects of state standards and standards implementation on secondary English teachers.

Design/methodology/approach

– Controversy surrounding standards implementation often includes balancing the struggle between teacher autonomy and district-mandated curriculum. The journey described here includes four roles in education: first, an undergraduate in a teacher education program at a state university; second, a classroom teacher learning to create pacing guides based on the standards; third, a graduate student writing a dissertation about standards implementation; and, fourth, a teacher educator who works with pre-service and practicing teachers.

Findings

– Educators at all levels must determine how to best navigate standards to help students succeed in the classroom, and what teaching practices must endure even in the face of increased standardization.

Originality/value

– Lack of curricular autonomy and few teacher-centered professional development opportunities during early standards implementation experiences led the author to understand the importance of a workshop model of standards implementation for teachers. In addition, strong support for reading and writing workshops in the secondary English Language Arts classroom is also provided, including the specific Common Core Standards met during these classroom activities.
The practice of reading aloud in the high school: a preliminary investigation
Authors: Warner Lionel , Crolla Caroline
Published: November 2015

Purpose

– The purpose of this paper is to investigate why reading aloud (RA), both by teachers and students, is such a common practice in high school classrooms. In particular, this investigation considers students’ views of why RA is practised and what are its effects.

Design/methodology/approach

– The paper presents the results of two small focus group discussions, in which high school students were given the opportunity to express their responses to the notion of RA in the classroom. Their responses are considered in the context of theoretical views of RA: pedagogical, reader-response and social/vocational.

Findings

– Analysis of responses revealed acknowledgement that RA is not only a useful skill but also that it is in the classroom, a site of anxiety and even conflict.

Research limitations/implications

– The sample is small and of very circumscribed generalisability. The students’ responses indicate further questions that might usefully be asked about the purpose and value of RA, in school and in society.

Practical implications

– The findings have implications for teachers’ practice, particularly in terms of the extent to which and the conditions in which students’ RA can develop confidence.

Originality/value

– Although much has been written about the use of RA with young children, it remains under-researched in mainstream high schools.
Complexity and leadership crisis in Africa
Authors: Olalere Anthony
Published: November 2015

Purpose

– The purpose of this paper is to evaluate a leadership crisis in Africa with the view to suggested new model that help overcome the leadership gap.

Design/methodology/approach

– This paper adopt the complexity leadership approach to explicate the leadership crisis in Africa.

Findings

– This paper suggested that the use of complexity leadership model of enabling leadership to better understand the complex leadership crisis.

Research limitations/implications

– The application of the leadership enables an appreciation of contemporary leadership realities.

Originality/value

– This paper adopting complexity leadership is novel and helps to fill the gap in understanding of present leadership crisis.
The effect of welding direction in the fatigue life of aluminium FS welded lap joints
Authors: Duarte F.F. , Infante Virgínia Isabel V. , Moreira P.M.G. , de Freitas M. , de Castro P.M.S.T.
Published: November 2015

Purpose

– Friction stir welding lap joints of aluminum alloy AA6082-T6 were joined using two distinct configurations. The purpose of this paper is to study the effect of the welding line direction on the fatigue life of the specimens. For that purpose, specimens with the welding line parallel to the loading direction and with the welding line perpendicular to the loading direction were designed and manufactured. Fatigue tests were performed under constant amplitude load and stress ratio of R=0.1. As shown in previous studies, the hook defect plays a decisive role in the mechanical behavior of the joint, in particular when submitted to fatigue. The specimen geometry with the welding line parallel to the loading direction showed a superior fatigue behavior: for a given number of cycles to rupture, the level of stress is approximately twice as high as for the perpendicular configuration.

Design/methodology/approach

– Two finite element models were created in order to study the behavior of the welded zone and, in particular, to compare influence of the hook defect in both configurations.

Findings

– The specimen geometry with the welding line parallel to the loading direction showed a superior fatigue behavior: for a given number of cycles to rupture, the level of stress is approximately twice as high as for the perpendicular configuration.

Originality/value

– The main objective of this work is to study the effect of the welding line direction on the fatigue life of the specimens. For that purpose, specimens with the welding line parallel to the loading direction and with the welding line perpendicular to the loading direction were designed and manufactured. Fatigue tests were performed under constant amplitude load and stress ratio of R=0.1. As shown in previous studies, the hook defect plays a decisive role in the mechanical behavior of the joint, in particular when submitted to fatigue.
SIF determination with digital image correlation
Authors: Tavares Paulo J , Ramos Tiago , Braga Daniel , Vaz Mario A P , Moreira Pedro Miguel Guimarães Pires
Published: November 2015

Purpose

– Hybrid methods, wherefore numerical and experimental data are used to calculate a critical parameter, have been used for several years with great success in Experimental Mechanics and, in particular, in fracture mechanics. The purpose of this paper is to report on the comparison of the strain field from numerical modelling forecasts against the experimental data obtained with the digital image correlation method under Mode II loading in fatigue testing. The numerical dual boundary element method has been established in the past as a very reliable method near singular regions where stresses tend to grow abruptly. The results obtained from the strain data near the crack tip were used in Williams expansion and agree fairly well with both the numerical results and the analytical solution proposed for pure Mode II testing.

Design/methodology/approach

– The work presented in this note is experimental. The proposed methodology is of an hybrid experimental/numerical nature in that a numerical stress intensity factor calculation hinges upon a stress field obtained with an image method.

Findings

– The obtained results are an important step towards the development of a practical tool for crack behaviour prediction in fatigue dominated events.

Research limitations/implications

– The results also stress the necessity of improving the experimental techniques to a point where the methods can be applied in real-life solicitations outside of laboratory premises.

Originality/value

– Although several research teams around the globe are presently working in this field, the present research topic is original and the proposed methodology has been presented initially by the research team years ago.
Effect of microtubule‐associated protein‐4 on epidermal cell migration under different oxygen concentrations
Authors: Chen Xin , Zhou Xin , Mao Tong‐Chun , Shi Xiao‐hua , Fan Dong‐li , Zhang Yi‐ming
Published: November 2015

After skin trauma, regional epidermal cell migration mediates the re‐epithelialization of the wound surface, which is an important step for wound healing, yet the underlying molecular regulatory mechanism is unclear. In the current study, HaCaT cells were maintained under different oxygen concentrations (1%, 21%, 40% and 65%). Technologies including immunofluorescence staining, wound scratch, transwell invasion, western blot and low‐expression lentiviral vector were utilized to observe the changes in microtubule dynamics and the microtubule‐associated protein (MAP)4 expression. MAP4's effect on cell migration under different oxygen concentrations was also studied. The results showed that under hyperoxic (40% and 65%) and hypoxic (1%) conditions, HaCaT cells were able to regulate cell microtubule dynamics by MAP4, thus promoting cell migration. On the other hand, MAP4 silencing through targeted shRNA attenuated HaCaT cell migration under the above oxygen concentrations. These results imply that MAP4 plays an important role in epidermal cell migration under different oxygen concentrations.
The Green House Model of Nursing Home Care in Design and Implementation
Authors: Cohen Lauren W. , Zimmerman Sheryl , Reed David , Brown Patrick , Bowers Barbara J. , Nolet Kimberly , Hudak Sandra , Horn Susan ,   the THRIVE Research Collaborative
Published: November 2015

Objective

To describe the Green House (GH) model of nursing home (NH) care, and examine how GH homes vary from the model, one another, and their founding (or legacy) NH.

Data Sources/Study Setting

Data include primary quantitative and qualitative data and secondary quantitative data, derived from 12 GH/legacy NH organizations February 2012—September 2014.

Study Design

This mixed methods, cross‐sectional study used structured interviews to obtain information about presence of, and variation in, GH‐relevant structures and processes of care. Qualitative questions explored reasons for variation in model implementation.

Data Collection/Extraction Methods

Interview data were analyzed using related‐sample tests, and qualitative data were iteratively analyzed using a directed content approach.

Principal Findings

GH homes showed substantial variation in practices to support resident choice and decision making; neither GH nor legacy homes provided complete choice, and all GH homes excluded residents from some key decisions. GH homes were most consistent with the model and one another in elements to create a real home, such as private rooms and baths and open kitchens, and in staff‐related elements, such as self‐managed work teams and consistent, universal workers.

Conclusions

Although variation in model implementation complicates evaluation, if expansion is to continue, it is essential to examine GH elements and their outcomes.
An Impact Velocity Device Design for Blood Spatter Pattern Generation with Considerations for High‐Speed Video Analysis,
Authors: Stotesbury Theresa , Illes Mike , Vreugdenhil Andrew J.
Published: November 2015

A mechanical device that uses gravitational and spring compression forces to create spatter patterns of known impact velocities is presented and discussed. The custom‐made device uses either two or four springs (k1 = 267.8 N/m, k2 = 535.5 N/m) in parallel to create seventeen reproducible impact velocities between 2.1 and 4.0 m/s. The impactor is held at several known spring extensions using an electromagnet. Trigger inputs to the high‐speed video camera allow the user to control the magnet's release while capturing video footage simultaneously. A polycarbonate base is used to allow for simultaneous monitoring of the side and bottom views of the impact event. Twenty‐four patterns were created across the impact velocity range and analyzed using HemoSpat. Area of origin estimations fell within an acceptable range (ΔXav = −5.5 ± 1.9 cm, ΔYav = −2.6 ± 2.8 cm, ΔZav = +5.5 ± 3.8 cm), supporting distribution analysis for the use in research or bloodstain pattern training. This work provides a framework for those interested in developing a robust impact device.
Preliminary Evidence for the Usefulness of Standardized Nursing Terminologies in Different Fields of Application: A Literature Review
Authors: Törnvall Eva , Jansson Inger
Published: November 2015

Purpose

To examine the effects of using standardized terminologies in nursing.

Methods

A systematic literature research was conducted in June 2015 going back to January 2007. A modified narrative synthesis was used as the structure for the analysis.

Results

Twenty‐three articles were included. Three themes were identified: enable evaluation of nursing‐sensitive outcome indicators, enable calculation of resource consumption, and characterize nursing care.

Conclusions

The studies included in the analysis described evidence for usefulness rather than effect. In all the studies, standardized nursing terminology was found to be essential for measuring, clarifying, and understanding nursing care.

Implications for Nursing Practice

The use of standardized terminologies could be advantageous. However, there are shortcomings in nursing documentation and the use of standardized nursing terminologies that obstruct evaluation of nursing care.
The rs5934505 single nucleotide polymorphism (SNP) is associated with low testosterone and late‐onset hypogonadism, but the rs10822184 SNP is associated with overweight and obesity in a Chinese Han population: a case–control study
Authors: Chen Y.‐p. , Nie L.‐L. , Li H.‐g. , Liu T.‐h. , Fang F. , Zhao K. , Yang R.‐f. , Ma X.‐l. , Kong X.‐b. , Zhang H.‐p. , Guan H.‐t. , Xia W. , Hong W.‐x. , Duan S. , Zeng X.‐c. , Shang X.‐j. , Zhou Y.‐z. , Gu Y.‐q. , Wu W.‐x. , Xiong C.‐l.
Published: November 2015

Low testosterone is associated with late‐onset hypogonadism (LOH) and obesity. Recently, studies have shown that four single nucleotide polymorphisms (SNPs), rs12150660, rs727428, rs5934505, and rs10822184, are associated with testosterone levels in populations of European descent. Therefore, we investigated whether the SNP loci are related to low testosterone, LOH, or obesity in a Chinese Han population. Ruling out co‐morbidities, DNA was prepared from 409 men (aged 40–65 years) with low serum testosterone (defined as total testosterone <11.6 nmol/L) and 1 : 1 normal controls (matched age, body mass index (BMI), and the same living area) who were selected from 6898 males. According to the same standards, 310 men with LOH and 1 : 1 normal controls were selected from 6898 males. Excluding the cases with an unreliable sequencing result, genetic analyses were performed. The minor allele frequencies of the SNP loci rs12150660, rs727428, rs5934505, and rs10822184 were 0.1%, 44.6%, 18.7%, and 38.9%, respectively. rs5934505 was associated with the serum total testosterone and calculated free testosterone (CFT) levels (p = 0.045 and p = 0.021). rs5934505 (C>T) was associated with an increased risk of low total testosterone, low CFT, and LOH and adjusted for other factors, with an odds ratio (OR) of 2.01 (1.34–3.01), 2.14 (1.42–3.20), and 1.64 (1.04–2.58). rs10822184 was significantly correlated with weight and BMI (p = 0.035 and p = 0.027). rs10822184 (T>C) was associated with an increased risk of overweight and obesity. We adjusted for other factors, with odds ratios (ORs) of 1.94 (1.36–2.78) and 1.56 (1.00–2.43). In summary, our study provided convincing evidence that rs5934505 (C>T) was associated with the risk of low testosterone and LOH in Chinese populations. We were the first to find that rs10822184 (T>C) was significantly correlated with the risk of overweight and obesity in Chinese populations. However, further large and functional studies are warranted to confirm our findings.
Epistemic Factors in Selective Exposure and Political Misperceptions on the Right and Left
Authors: Meirick Patrick C. , Bessarabova Elena
Published: November 2015

Selective news media exposure and political misperceptions have potentially troubling implications for democracy. In an online survey (N = 486) conducted in the context of the 2012 U.S. presidential election, we drew on a motivated reasoning framework to examine how rational and experiential engagement and need for closure were related to selective exposure and misperceptions. Because previous research has focused on conservative media and misperceptions that serve Republican causes, we also looked at how conservative and liberal media exposure were related to Republican‐ and Democratic‐serving misperceptions among the overall sample as well as respondents of each party. Rational engagement had positive relationships with media use and (surprisingly) selective exposure among Democrats. It also was negatively related with Republican‐serving misperceptions. Experiential engagement, on the other hand, had no relationships with media use but was positively related to Republican‐serving misperceptions. Need for closure was positively related to Republican‐serving misperceptions, but not after control variables were added. Finally, exposure to either kind of partisan media both discouraged misperceptions that served the opposing party and promoted misperceptions that served their own party, although the extent to which it did so appeared to vary depending on the partisanship of the media and of the audience. Implications of these findings for theory and policy are discussed.
Interspecific variation in ovipositor morphology among Manaosbiid and Nomoclastid Harvestmen (Arachnida, Opiliones, Laniatores)
Authors: Brooks Emily A. , Townsend Victor R. , Allen Elizabeth A. , Tuthill Margaret A.
Published: November 2015

The external anatomy of the ovipositor has generally been overlooked as a source of informative characters in systematic studies of laniatorean harvestmen. In this study, we used scanning electron microscopy to examine the ovipositors of nine species representing the families Manaosbiidae (five species) and Nomoclastidae (four species). Similar to the ovipositor morphology of many gonyleptoidean families, the distal tips of the ovipositors of these harvestmen have four external lobes, with the margins most commonly adorned with 10 large peripheral setae. In manaosbiid and nomoclastid species, these peripheral setae have undivided bases, striated shafts and undivided distal tips. There are typically three setae on each anterior lobe and two setae on each posterior lobe. The medial setae on both anterior and posterior lobes insert into sockets that are slightly more dorsal. We observed small, surface denticles, usually associated with a pore, on the external surface of the lobes. There was interspecific and intraspecific variation in the number and shape of these surface denticles. The association of pores with denticles on the ovipositor appears to be a feature common to not only both families but is also a trait that has not been observed on ovipositors in other families of laniatorean harvestmen.
Application of a novel collaboration engineering method for learning design: A case study
Authors: Cheng Xusen , Li Yuanyuan , Sun Jianshan , Huang Jianqing
Published: November 2015

Collaborative case studies and computer‐supported collaborative learning (CSCL) play an important role in the modern education environment. A number of researchers have given significant attention to learning design in order to improve the satisfaction of collaborative learning. Although collaboration engineering (CE) is a mature method widely used for collaboration design, there is limited research as to whether CE is useful for learning design, in particular, case studies. Therefore, in this paper, we designed a contrastive case study in two small classes of a Chinese university. In the first part, we encouraged a teacher to use CE tools to design a learning process. Since Chinese students had limited access to CE platforms, we used our special tool—the Discussion Platform as the main CE tool. A total of 40 students and a teacher collaborated in our first experiment and were asked to complete a survey upon completion of the interviews. In our comparison study, the teacher gave the same task to another 31 students, yet omitted the use of CE tools to design the learning process. In this paper, we compare the results obtained and determine the advantage that CE methods have on learning effectiveness and student satisfaction.