bluuebunny/crossref_metadata_2025 huggingface dataset:
Plasmonic kinks and walking solitons in nonlinear lattices of metal nanoparticles
Authors: Noskov Roman E. , Smirnova Daria A. , Kivshar Yuri S.
Published: September 2014

We study nonlinear effects in one-dimensional (1D) arrays and two-dimensional (2D) lattices composed of metallic nanoparticles with the nonlinear Kerr-like response and an external driving field. We demonstrate the existence of families of moving solitons in 1D arrays and characterize their properties such as an average drifting velocity. We also analyse the impact of varying external field intensity and frequency on the structure and dynamics of kinks in 2D lattices. In particular, we identify the kinks with positive, negative and zero velocity as well as breathing kinks with a self-oscillating profile.
Chaoticon: localized pattern with permanent dynamics
Authors: Verschueren N. , Bortolozzo U. , Clerc M. G. , Residori S.
Published: September 2014

An analytical mechanism that support localized spatio-temporal chaos is provided. We consider a simple model—
the Nagumo Kuramoto model
—which contains the crucial ingredients for observing localized spatio-temporal chaos, namely, the spatio-temporal chaotic pattern and its coexistence with a uniform state. This model allows us to unveil the front dynamics and to show that it can be described by a chaotic motor corresponding to the deterministic counterpart of a Brownian motor. Front interaction is identified as the mechanism at the origin of the localized spatio-temporal chaotic structures.
Localized modes in dissipative lattice media: an overview
Authors: He Yingji , Malomed Boris A. , Mihalache Dumitru
Published: September 2014

We give an overview of recent theoretical studies of the dynamics of one- and two-dimensional spatial dissipative solitons in models based on the complex Ginzburg–Landau equations with the cubic–quintic combination of loss and gain terms, which include imaginary, real or complex spatially periodic potentials. The imaginary potential represents periodic modulation of the local loss and gain. It is shown that the effective gradient force, induced by the inhomogeneous loss distribution, gives rise to three generic propagation scenarios for one-dimensional dissipative solitons: transverse drift, persistent swing motion, and damped oscillations. When the lattice-average loss/gain value is zero, and the real potential has spatial parity opposite to that of the imaginary component, the respective complex potential is a realization of the parity-time symmetry. Under the action of lattice potentials of the latter type, one-dimensional solitons feature motion regimes in the form of the transverse drift and persistent swing. In the two-dimensional geometry, three types of axisymmetric radial lattices are considered, namely those based solely on the refractive-index modulation, or solely on the linear-loss modulation, or on a combination of both. The rotary motion of solitons in such axisymmetric potentials can be effectively controlled by varying the strength of the initial tangential kick.
Temporal localized structures in photonic crystal fibre resonators and their spontaneous symmetry-breaking instability
Authors: Bahloul L. , Cherbi L. , Hariz A. , Tlidi M.
Published: September 2014

We investigate analytically and numerically the formation of temporal localized structures (TLSs) in an all photonic crystal fibre resonator. These dissipative structures consist of isolated or randomly distributed peaks in a uniform background of the intensity profile. The number of peaks and their temporal distribution are determined solely by the initial conditions. They exhibit multistability behaviour for a finite range of parameters. A weakly nonlinear analysis is performed in the neighbourhood of the first threshold associated with the modulational instability. We consider the regime where the instability is not degenerate. We show that fourth-order dispersion affects the threshold associated with the formation of bright TLSs. We estimate both analytically and numerically the linear and nonlinear corrections to the velocity of moving temporal structures induced by spontaneous broken reflection symmetry mediated by third-order dispersion. Finally, we show that third-order dispersion affects the threshold associated with the moving TLSs.
Minimal mechanisms for vegetation patterns in semiarid regions
Authors: Martínez-García Ricardo , Calabrese Justin M. , Hernández-García Emilio , López Cristóbal
Published: September 2014

The minimal ecological requirements for the fomation of regular vegetation patterns in semiarid systems have been recently questioned. Against the general belief that a combination of facilitative and competitive interactions is necessary, recent theoretical studies suggest that, under broad conditions, non-local competition among plants alone may induce patterns. In this paper, we review results along this line, presenting a series of models that yield spatial patterns when finite-range competition is the only driving force. A preliminary derivation of this type of model from a more detailed one that considers water–biomass dynamics is also presented.
Plant clonal morphologies and spatial patterns as self-organized responses to resource-limited environments
Authors: Couteron P. , Anthelme F. , Clerc M. , Escaff D. , Fernandez-Oto C. , Tlidi M.
Published: September 2014

We propose here to interpret and model peculiar plant morphologies (cushions and tussocks) observed in the Andean Altiplano as localized structures. Such structures resulting in a patchy, aperiodic aspect of the vegetation cover are hypothesized to self-organize thanks to the interplay between facilitation and competition processes occurring at the scale of basic plant components biologically referred to as ‘ramets’. (Ramets are often of clonal origin.) To verify this interpretation, we applied a simple, fairly generic model (one integro-differential equation) emphasizing via Gaussian kernels non-local facilitative and competitive feedbacks of the vegetation biomass density on its own dynamics. We show that under realistic assumptions and parameter values relating to ramet scale, the model can reproduce some macroscopic features of the observed systems of patches and predict values for the inter-patch distance that match the distances encountered in the reference area (Sajama National Park in Bolivia). Prediction of the model can be confronted in the future with data on vegetation patterns along environmental gradients so as to anticipate the possible effect of global change on those vegetation systems experiencing constraining environmental conditions.
An Approximate Bayesian Computation Approach to Examining the Phylogenetic Relationships among the Four Gibbon Genera using Whole Genome Sequence Data
Authors: Veeramah Krishna R. , Woerner August E. , Johnstone Laurel , Gut Ivo , Gut Marta , Marques-Bonet Tomas , Carbone Lucia , Wall Jeff D. , Hammer Michael F.
Published: September 2014

Gibbons are believed to have diverged from the larger great apes ∼16.8 Mya and today reside in the rainforests of Southeast Asia. Based on their diploid chromosome number, the familyHylobatidaeis divided into four genera,Nomascus,Symphalangus,HoolockandHylobates. Genetic studies attempting to elucidate the phylogenetic relationships among gibbons using karyotypes, mtDNA, the Y chromosome, and short autosomal sequences have been inconclusive. To examine the relationships among gibbon genera in more depth, we performed 2nd generation whole genome sequencing to a mean of ∼15X coverage in two individuals from each genus. We developed a coalescent-based Approximate Bayesian Computation method incorporating a model of sequencing error generated by high coverage exome validation to infer the branching order, divergence times, and effective population sizes of gibbon taxa. AlthoughHoolockandSymphalangusare likely sister taxa, we could not confidently resolve a single bifurcating tree despite the large amount of data analyzed. Our combined results support the hypothesis that all four gibbon genera diverged at approximately the same time. Assuming an autosomal mutation rate of 1×10−9/site/year this speciation process occurred ∼5 Mya during a period in the Early Pliocene characterized by climatic shifts and fragmentation of the Sunda shelf forests. Whole genome sequencing of additional individuals will be vital for inferring the extent of gene flow among species after the separation of the gibbon genera.
Viscous deformation of relaxing ventricle and pulsatile blood propelling (numerical model)
Authors: Kamnev Yuri
Published: September 2014

The numerical model of one-loop circulation exploits viscous deformation as mechanism of ventricular filling. Mathematical advantage of viscous deforming is a possibility to present the ventricular filling as the function of two independent variables (stress and time); two-dimensional argument frames a table which permits to calculate end-diastolic ventricular volume due to information about measured venous pressure and duration of ventricular diastole. The equation was deduced which balances the system while varying of such parameters as arterial resistance, the value of normal rhythm and the volume flow rate. The model pays attention on the phenomenon of asymmetrical position of normal rhythm (the steady rhythm in conditions of rest) and explains why the operating range of brady-rhythms is much narrower than the operating range of tachy-rhythms.
Crystal structure of 2-ethyl-3-(4-fluorophenylsulfonyl)-5,7-dimethyl-1-benzofuran
Authors: Choi Hong Dae , Lee Uk
Published: September 2014

In the title compound, C18H17FO3S, the dihedral angle between the plane of the benzofuran ring [r.m.s. deviation = 0.006 (1) Å] and that of the 4-fluorophenyl ring [r.m.s. deviation = 0.004 (1) Å] is 82.45 (4)°. In the crystal, molecules are linkedviathree different pairs of C—H...O hydrogen bonds, forming chains along [001] and enclosing twoR22(10) and oneR22(12) ring motifs. The chains are further linked by π–π interactions [inter-centroid distance = 3.566 (1) Å] between the furan rings of inversion-related molecules, forming a two-dimensional network lying parallel to (100).
Crystal structure of 9-(4-bromobutyl)-9H-fluorene-9-carboxylic acid
Authors: Zhang Xu-Yang , Liu Bing-Ni , Wang Ping-Bao , Liu Deng-Ke
Published: September 2014

The title compound, C18H17BrO2, is a key intermediate in the synthesis of lomitapide mesylate, a microsomal triglyceride transfer protein inhibitor. Its asymmetric unit contains two independent molecules with slightly different conformations; the mean planes of the 4-bromobutyl and carboxylate groups in the two molecules form dihedral angles of 24.54 (12) and 17.10 (18)°. In the crystal, carboxylate groups are involved in O—H...O hydrogen bonding, which leads to the formation of two crystallographically independent centrosymmetric dimers. Weak intermolecular C—H...O interactions further link these dimers into layers parallel to thebcplane.
Crystal structure of 4-(1H-indol-3-yl)-2-(4-methoxyphenyl)-6-phenylpyridine-3-carbonitrile
Authors: Vishnupriya R. , Suresh J. , Sakthi Marimuthu , Perumal Subbu , Lakshman P. L. Nilantha
Published: September 2014

In the title compound, C27H19N3O, the dihedral angles between the plane of the pyridine ring and those of the indole (r.m.s. deviation = 0.018 Å), phenyl and methoxybenzene substituents are 33.60 (6), 25.28 (7) and 49.31 (7)°, respectively. The N atom of the carbonitrile group is significantly displaced [0.288 (2) Å] from the plane of the pyridine ring, perhaps due to steric crowding. In the crystal, inversion dimers linked by pairs of N—H...Nn(n = nitrile) hydrogen bonds generateR22(16) loops. Aromatic π–π stacking [centroid–centroid separation = 3.6906 (7) Å] and very weak C—H...π interactions are also observed".
Crystal structure of [2,6-bis(adamantan-1-yl)-4-tert-butylphenolato-κO]dimethylaluminium(III)
Authors: Wang Lei , Yang Li
Published: September 2014

The title compound, [Al(CH3)2(C30H41O)] is synthesized by the reaction of 2,6-di-adamantyl-4-tert-butyl-phenol with Al(CH3)3in a nitrogen atmosphere. In the molecule, the coordination geometry around the AlIIIatom is slightly distorted C2O trigonal (the sum of the bond angles subtended at Al atom being 359.9°), which is rarely reported for organometallic aluminium compounds. The coordination plane is approximately perpendicular to the benzene ring [the dihedral angle = 87.73 (16)°]. There is no intermolecular hydrogen bonding in the crystal structure.
Time dependence of X-ray polarizability of a crystal induced by an intense femtosecond X-ray pulse
Authors: Leonov A. , Ksenzov D. , Benediktovitch A. , Feranchuk I. , Pietsch U.
Published: September 2014

The time evolution of the electron density and the resulting time dependence of Fourier components of the X-ray polarizability of a crystal irradiated by highly intense femtosecond pulses of an X-ray free-electron laser (XFEL) is investigated theoretically on the basis of rate equations for bound electrons and the Boltzmann equation for the kinetics of the unbound electron gas. The photoionization, Auger process, electron-impact ionization, electron–electron scattering and three-body recombination have been implemented in the system of rate equations. An algorithm for the numerical solution of the rate equations was simplified by incorporating analytical expressions for the cross sections of all the electron configurations in ions within the framework of the effective charge model. Using this approach, the time dependence of the inner shell populations during the time of XFEL pulse propagation through the crystal was evaluated for photon energies between 4 and 12 keV and a pulse width of 40 fs considering a flux of 1012 photons pulse−1(focusing on a spot size of ∼1 µm). This flux corresponds to a fluence ranging between 0.8 and 2.4 mJ µm−2. The time evolution of the X-ray polarizability caused by the change of the atomic scattering factor during the pulse propagation is numerically analyzed for the case of a silicon crystal. The time-integrated polarizability drops dramatically if the fluence of the X-ray pulse exceeds 1.6 mJ µm−2.
Contributions of charge-density research to medicinal chemistry
Authors: Dittrich Birger , Matta Chérif F.
Published: September 2014

This article reviews efforts in accurate experimental charge-density studies with relevance to medicinal chemistry. Initially, classical charge-density studies that measure electron density distributionvialeast-squares refinement of aspherical-atom population parameters are summarized. Next, interaction density is discussed as an idealized situation resembling drug–receptor interactions. Scattering-factor databases play an increasing role in charge-density research, and they can be applied both to small-molecule and macromolecular structures in refinement and analysis; software development facilitates their use. Therefore combining both of these complementary branches of X-ray crystallography is recommended, and examples are given where such a combination already proved useful. On the side of the experiment, new pixel detectors are allowing rapid measurements, thereby enabling both high-throughput small-molecule studies and macromolecular structure determination to higher resolutions. Currently, the most ambitious studies compute intermolecular interaction energies of drug–receptor complexes, and it is recommended that future studies benefit from recent method developments. Selected new developments in theoretical charge-density studies are discussed with emphasis on its symbiotic relation to crystallography.
Automated nucleic acid chain tracing in real time
Authors: Cowtan Kevin
Published: September 2014

The crystallographic structure solution of nucleotides and nucleotide complexes is now commonplace. The resulting electron-density maps are often poorer than for proteins, and as a result interpretation in terms of an atomic model can require significant effort, particularly in the case of large structures. While model building can be performed automatically, as with proteins, the process is time-consuming, taking minutes to days depending on the software and the size of the structure. A method is presented for the automatic building of nucleotide chains into electron density which is fast enough to be used in interactive model-building software, with extended chain fragments built around the current view position in a fraction of a second. The speed of the method arises from the determination of the `fingerprint' of the sugar and phosphate groups in terms of conserved high-density and low-density features, coupled with a highly efficient scoring algorithm. Use cases include the rapid evaluation of an initial electron-density map, addition of nucleotide fragments to prebuilt protein structures, and in favourable cases the completion of the structure while automated model-building software is still running. The method has been incorporated into theCootsoftware package.
Location of Cu2+in CHA zeolite investigated by X-ray diffraction using the Rietveld/maximum entropy method
Authors: Andersen Casper Welzel , Bremholm Martin , Vennestrøm Peter Nicolai Ravnborg , Blichfeld Anders Bank , Lundegaard Lars Fahl , Iversen Bo Brummerstedt
Published: September 2014

Accurate structural models of reaction centres in zeolite catalysts are a prerequisite for mechanistic studies and further improvements to the catalytic performance. The Rietveld/maximum entropy method is applied to synchrotron powder X-ray diffraction data on fully dehydrated CHA-type zeolites with and without loading of catalytically active Cu2+for the selective catalytic reduction of NOxwith NH3. The method identifies the known Cu2+sites in the six-membered ring and a not previously observed site in the eight-membered ring. The sum of the refined Cu occupancies for these two sites matches the chemical analysis and thus all the Cu is accounted for. It is furthermore shown that approximately 80% of the Cu2+is located in the new 8-ring site for an industrially relevant CHA zeolite with Si/Al = 15.5 and Cu/Al = 0.45. Density functional theory calculations are used to corroborate the positions and identity of the two Cu sites, leading to the most complete structural description of dehydrated silicoaluminate CHA loaded with catalytically active Cu2+cations.
Effects of role models and gender on students’ entrepreneurial intentions
Authors: Karimi Saeid , J.A. Biemans Harm , Lans Thomas , Chizari Mohammad , Mulder Martin
Published: September 2014

Purpose

– This paper aims to, drawing on the theory of planned behaviour (TPB), explore the effects of entrepreneurial role models on entrepreneurial intention (EI) and its antecedents and examines the question of whether the effects vary by gender.

Design/methodology/approach

– Data were collected from a sample of 331 students at seven universities in Iran. Structural equation modelling and bootstrap procedure were used to analyse the data.

Findings

– Consistent with the TPB, our results show entrepreneurial role models to indirectly influence EIs via the antecedents of intention. No gender differences in the relationship between perceived behaviour control and EIs were found, but gender did moderate the other relationships within the TPB. Attitude towards entrepreneurship was a weaker predictor and subjective norms a stronger predictor of EIs for female students than for their male counterparts. Furthermore, perceived behaviour control and attitudes towards entrepreneurship were more strongly influenced by role models for females as opposed to male students.

Research limitations/implications

– Future studies should go beyond examining the mere fact of knowing entrepreneurial role models to examine the mechanisms underlying the relationship between role models and EIs.

Practical implications

– The results of this study have clear implications for both educators and policymakers.

Originality/value

– The study contributes to the entrepreneurship literature by incorporating entrepreneurial role models and gender into the TPB and investigating their mediating and moderating effects within the model.
Transfer of learning
Authors: Renta-Davids Ana-Inés , Jiménez-González José-Miguel , Fandos-Garrido Manel , González-Soto Ángel-Pío
Published: September 2014

Purpose

– This paper aims to analyse transfer of learning to workplace regarding to job-related training courses. Training courses analysed in this study are offered under the professional training for employment framework in Spain.

Design/methodology/approach

– During the training courses, trainees completed a self-reported survey of reasons for participation (time 1 data collection, N = 447). Two months after training, a second survey was sent to the trainees by email (time 2 data collection, N = 158). Factor analysis, correlations and multiple hierarchical regressions were performed.

Findings

– The results of this study demonstrate the importance of training relevance and training effectiveness in transfer of training. Results indicated that relevance, the extent training courses were related to participant’s workplace activities and professional development, positively influences transfer of training. Effectiveness, training features which facilitated participants to acquire knowledge and skills, also has a significantly positive influence in transfer of training. Motivation to participate and learning-conducive workplace features also have a positive influence in transfer of training.

Originality/value

– This study contributes to the understanding of transfer of learning in work-related training programmes by analysing the factors that influence transfer of learning back to the workplace. The study has practical implication for training designers and education providers to enhance work-related training in the context of the Professional Training for Employment Subsystem in Spain.
Mobility and structural change through traumatic organizational events
Authors: Drew Sellers R. , J. Fogerty Timothy , M. Parker Larry
Published: September 2014

Purpose

– This paper aims to, using evidence from a former office of the public accounting firm Arthur Andersen, to study the importance of the relational content and structure of individuals’ social connections as they transitioned to subsequent employment. The paper also examines the maintenance of their social networks through time. Implications for careers in the accounting field are offered. Practicing accountants’ connections with other individuals have often been recognized as an important resource that influences career success. However, these social networks have escaped systematic academic study in accounting.

Design/methodology/approach

– Social network analysis, built on survey data.

Findings

– The results show that who one was connected to in a previous employment was more important than one’s overall network position when deciding whether to stay or exit public accounting. However those who exited public accounting did not demonstrate a handicap in maintaining network structures after the disbanding of the firm.

Research limitations/implications

– This study is limited to firm members, and to a single office of a firm. Social network analysis was used as a research tool for the sociology of public accounting.

Practical implications

– Implications are for careers in public accounting, and the management of human resources in public accounting is offered.

Social implications

– The paper has implications for the successfulness of professional service provision in a general sense.

Originality/value

– Almost a decade of social connection is studied with a method that has not appeared in the discipline but is well regarded in management studies.
Beyond Budgeting and change: a case study
Authors: Sandalgaard Niels , Nikolaj Bukh Per
Published: September 2014

Purpose

– This paper aims to investigate reasons for going Beyond Budgeting and the practical issues organizations face when they change their management accounting system based on inspiration from the Beyond Budgeting model.

Design/methodology/approach

– The authors apply a case study approach. The primary data source is interviews. The case company is a global company in the agri-food industry that is organized as a cooperative.

Findings

– The authors propose that many organizations that change their management accounting system on the basis of inspiration from Beyond Budgeting will maintain fixed budget targets. Furthermore, the authors propose that even when the use of budgets at the corporate level focuses on few line items, the diagnostic use of budgeting at lower levels in the organization may focus on a larger number of line items.

Research limitations/implications

– The study is subject to the usual limitations of case-based research. The propositions made in the paper should be further investigated in other organizations attempting to change their management accounting system with inspiration from Beyond Budgeting.

Practical implications

– This study shows that the lack of internal benchmarks and the need to deliver the expected results to the company’s owners might hinder the implementation of the Beyond Budgeting model as described in the practitioner-based Beyond Budgeting literature.

Originality/value

– The paper is one of the few case studies in the academic literature to analyze the practical issues organizations face when changing their way of budgeting on the basis of inspiration from Beyond Budgeting.
Financial disclosure and performance of microfinance institutions
Authors: Quayes Shakil , Hasan Tanweer
Published: September 2014

Purpose

– The purpose of this paper is to analyze the relationship between financial disclosure and the financial performance of microfinance institutions (MFIs).

Design/methodology/approach

– The paper utilizes ordinary least squares method to analyze the impact of disclosure on financial performance, an ordered probit model to investigate the possible effect of financial performance on disclosure and utilizes a three-stage least squares method to delineate the endogenous relationship between disclosure and financial performance of MFIs.

Findings

– The paper finds that better disclosure has a statistically significant positive impact on operational performance of MFIs; second, it also shows that improved financial performance results in better financial disclosure. Keeping the endogenous nature of the relationship between disclosure and performance, the paper uses a three-stage least squares method to show that disclosure and financial performance positively affect each other simultaneously.

Research limitations/implications

– The paper attempts to delineate a positive association between better disclosure on financial performance of MFIs, which can be used for developing a better disclosure policy by management, formulating more effective guidelines for disclosure by the stakeholders and mandating more appropriate laws and uniform disclosure practice by regulators.

Originality/value

– This is the first study that uses a large number of MFIs from 75 countries; second, it uses a uniform scale of designating a disclosure rating (assigned by MIX Market) to show the relationship between disclosure and performance. Finally, it uses three-stage least squares method to address the possible endogeneity between disclosure and performance.
Interactive effects of a non‐native invasive grassMicrostegium vimineumand herbivore exclusion on experimental tree regeneration under differing forest management
Authors: Johnson Daniel J. , Flory S. Luke , Shelton Angela , Huebner Cynthia , Clay Keith
Published: September 2014

Invasive plants, herbivores and site management history can play crucial roles in determining plant community composition. The net effects of invasive species on plant communities are well known, but we have a poor understanding of the relative contributions of direct competitive effects of invasive species and their interactions with herbivores and management practices. Understanding interactions among plant invasions, herbivores and management history is critical for predicting and managing long‐term ecological effects of invasions on native communities.

We investigated the effects of the invasive annual grassMicrostegium vimineum, vertebrate herbivory, site management history and their interactions on seedling performance of five native tree species in six forest sites. Half of the sites had been subjected to recent timber harvesting, and half had not been managed for timber for at least 20 years. We evaluated tree seedling survival and biomass after two growing seasons in blocked split‐plots where the invasive grass was present or experimentally removed and where vertebrate herbivores were excluded by fencing or allowed onto the plots.

Removal of the invasive grass and herbivore exclosures both had positive effects on seedling survival. Survival of all species was significantly increased by removal or by the interaction of removal with exclosure or timber harvest history. There was a significant interaction between exclosure and removal on seedling biomass where seedlings were larger in exclosure treatments with the invasive removed but smaller in exclosure treatments when the invader was present. Mean seedling biomass was 79·6% greater in harvested sites than in non‐harvested sites. The significant positive effects of removal and recent timber harvest on the biomass of twoQuercusspecies suggest strong impacts of invasion and management history on this important genus.

Synthesis and applications. An invasive grass directly inhibited tree seedling performance but effects depended on herbivore exclusion treatment, timber harvest history and tree species. Our results suggest that forest management strategies should incorporate invasive plant control given that regeneration of desirable tree species can be influenced by plant invasions and their interactions with herbivores and previous management practices.
Pollination mitigates cucumber yield gaps more than pesticide and fertilizer use in tropical smallholder gardens
Authors: Motzke Iris , Tscharntke Teja , Wanger Thomas C. , Klein Alexandra‐Maria
Published: September 2014

Pollination can be an essential but often neglected ecosystem service to mitigate crop yield gaps. Pollination services are usually studied in isolation, and their relative role and possible interactions with other factors, such as major management practices, is little understood.

We tested how pollination (insect vs. wind‐ and self‐pollination) interacts with weed control, fertilization and insect herbivore control and how these factors as well as flower‐visiting bees influence fruit set and yield of cucumber Cucumis sativus L. in 13 traditional Indonesian home gardens.

Although insect pollination, fertilization and weed control additively increased crop yield, fertilization and weed control alone could not compensate for pollination loss. Pollination individually accounted for 75% of the yield and was, hence, the most important driver of yield. In contrast, herbivore control through insecticides at commonly applied levels did not increase yield.

Yield strongly increased with higher number of flower‐visiting bee individuals, while the number of bee individuals in turn was not influenced by weed control, fertilization or herbivore control, but increased with higher number of cucumber flowers.

Synthesis and applications. Although multiple management practices influence yield, they cannot compensate yield gaps from pollinator loss in cucumber smallholder production in Indonesia. Our results also show that the widespread use of insecticides without considering the impacts on pest reduction is uneconomical. Here, reducing insecticides caused no income loss and, at the same time, reduces potential risks to important pollinators, which needs to be acknowledged by policy‐driven regulations for pesticide application in tropical agroecosystems. Our results stress the importance of enhancing bee populations to facilitate pollination services. Bee management practices, such as sustaining additional food resources for pollinators, need to be established.
Teaching Regulatory Humility: Experimenting with Student Practitioners
Authors: Dunlop Claire A. , Radaelli Claudio M.
Published: September 2014

Donald Schön’s assertion that becoming an effective professional requires more than technical rationality underpins the pedagogy of Masters in Public Administration (MPA) programmes. This article explores how public administrators can be taught to think reflectively and reflexively about the limits of control in the context of decision making and regulatory policy appraisal. It reports on an in-class pedagogical experiment on illusions of control used to generate a real-life experience of the cognitive and emotional dimensions of control. By doing so, the article introduces the concept of ‘regulatory humility’ and contributes to the literature on experiments as pedagogical tools, and to debates on teaching methods in public administration and political science.
Narrating One Nation: The Ideology and Rhetoric of the Miliband Labour Party
Authors: Atkins Judi
Published: September 2014

Speaking at the 2012 Labour Party Conference, Ed Miliband set out his vision of ‘One Nation’. This article maps the core concepts of Labour's ideology and identifies the narratives used to argue for One Nation social security reform. It locates these narratives within Labour's traditions and demonstrates that they coalesce in the leadership persona of Miliband himself. Though an attempt to respond to a populist ‘rhetorical culture’, the article contends that this strategy has created a self-enclosed ideology that cannot conceive of an audience beyond itself. Labour therefore needs to overcome this solipsism if it is to secure victory in 2015.
Heavy–light, absent–present: rethinking the ‘weight’ of imprisonment
Authors: Crewe Ben , Liebling Alison , Hulley Susie
Published: September 2014

SinceKing andMcDermott (1995), followingDownes (1988), defined the psychological oppressiveness of incarceration in terms of ‘weight’, little has been written about the ‘weight of imprisonment’. None the less, it is generally assumed that prisons that are ‘light’ are preferable to those that are ‘heavy’ – in part because of an assumption among many penologists that power, and its application, is dangerous and antagonistic. This article does not dispute that ‘heavy’ prisons are undesirable. Its argument is that there can also be dangers if prisons are excessively light. Many of these dangers are linked to the under‐use of power. The tone and quality of prison life depends on the combined effects of institutional weight with the ‘absence’ or ‘presence’ of staff power. Drawing on prisoners' descriptions of their experiences in public and private sector prisons, and their assessments of important aspects of their quality of life, the article outlines what these concepts mean in practice. The authors develop a four‐quadrant framework for conceptualizeng penal legitimacy and the experience of penal authority.
If it didn't exist we'd have to invent it … Further reflections on the ontological status of the state
Authors: Hay Colin
Published: September 2014

In this brief response to Bob Jessop's probing yet sympathetic critique, I clarify further the ‘as if realist’ political ontology of the state. I suggest that critical realism's appeal to the ontological stratification of social reality and to the logic of retroduction are the principal stumbling blocks for ‘as if realists’, that the appeal to state power(s) as distinct from the state as real cannot circumvent the ‘as if realist’ ontological objection to the state as real since both remain conceptual abstractions, but that there is a natural affinity between the strategic‐relational approach developed by Jessop and others and the ‘as if realist’ ontology of the state that I here elucidate.
Towards a political ontology of state power: a comment on Colin Hay's article
Authors: Jessop Bob
Published: September 2014

This article offers some critical realist, strategic‐relational comments on Colin Hay's proposal to treat the state as an ‘as‐if‐real’ concept. The critique first develops an alternative account of ontology, which is more suited to analyses of the state and state power; it then distinguishes the ‘intransitive’ properties of the real world as an object of investigation from the ‘transitive’ features of its scientific investigation and thereby provides a clearer understanding of what is at stake in ‘as‐if‐realism’; and it ends with the suggestion that a concern with the modalities of state power rather than with the state per se offers a more fruitful approach to the genuine issues raised in Hay's article and in his earlier strategic‐relational contributions to political analysis.
Disparities in Perinatal Quality Outcomes for Very Low Birth Weight Infants in Neonatal Intensive Care
Authors: Lake Eileen T. , Staiger Douglas , Horbar Jeffrey , Kenny Michael J. , Patrick Thelma , Rogowski Jeannette A.
Published: September 2014

Objective

To determine if hospital‐level disparities in very low birth weight (VLBW) infant outcomes are explained by poorer hospital nursing characteristics.

Data Sources

Nurse survey and VLBW infant registry data.

Study Design

Retrospective study of 8,252 VLBW infants in 98 Vermont Oxford Network hospital neonatal intensive care units (NICUs) nationally. NICUs were classified into three groups based on their percent of infants of black race. Two nurse‐sensitive perinatal quality standards were studied: nosocomial infection and breast milk.

Data Collection

Primary nurse survey (N = 5,773, 77 percent response rate).

Principal Findings

VLBW infants born in high‐black concentration hospitals had higher rates of infection and discharge without breast milk than VLBW infants born in low‐black concentration hospitals. Nurse understaffing was higher and practice environments were worse in high‐black as compared to low‐black hospitals. NICU nursing features accounted for one‐third to one‐half of the hospital‐level health disparities.

Conclusions

Poorer nursing characteristics contribute to disparities in VLBW infant outcomes in two nurse‐sensitive perinatal quality standards. Improvements in nursing have potential to improve the quality of care for seven out of ten black VLBW infants who are born in high‐black hospitals in this country.
Patient‐Perceived Pressure from Clinicians for Labor Induction and Cesarean Delivery: A Population‐Based Survey of U.S. Women
Authors: Jou Judy , Kozhimannil Katy B. , Johnson Pamela Jo , Sakala Carol
Published: September 2014

Objective

To determine whether patient‐perceived pressure from clinicians for labor induction or cesarean delivery is significantly associated with having these procedures.

Data Sources/Study Setting

Listening to Mothers III, a nationally representative survey of women 18–45 years who delivered a singleton infant in a U.S. hospital July 2011–June 2012 (N = 2,400).

Study Design

Multivariate logistic regression analysis of factors associated with perceived pressure and estimation of odds of induction and cesarean given perceived pressure.

Principal Findings

Overall, 14.8 percent of respondents perceived pressure from a clinician for labor induction and 13.3 percent for cesarean delivery. Women who perceived pressure for labor induction had higher odds of induction overall (adjusted odds ratio [aOR]: 3.51; 95 percent confidence interval [CI]: 2.5–5.0) and without medical reason (aOR: 2.13; 95 percent CI: 1.3–3.4) compared with women who did not perceive pressure. Those perceiving pressure for cesarean delivery had higher odds of cesarean overall (aOR: 5.17; 95 percent CI: 3.2–8.4), without medical reason (aOR: 6.13; 95 percent CI: 3.4–11.1), and unplanned cesarean (aOR: 6.70; 95 percent CI: 4.0–11.3).

Conclusions

Patient‐perceived pressure from clinicians significantly predicts labor induction and cesarean delivery. Efforts to reduce provider–patient miscommunication and minimize potentially unnecessary procedures may be warranted.
Agricultural Financial Risks Resulting from Extreme Events
Authors: Xouridas Stergios
Published: September 2014

Decision‐makers in the agricultural sector operate in a volatile and risky environment. The statistical assessment of agricultural commodity prices is necessary to deduce the stylised facts of agricultural markets and guide the action of market participants. This article examines the kurtosis values of 60 agricultural commodities and presents evidence that the distributions of their returns are fat‐tailed. We use power‐law distributions to model the tail returns and the possible time‐varying extreme event risks in commodity markets. Our results suggest that the usefulness of the value at risk and expected shortfall as risk management tools is questionable.
Evaluating Extraction Conditions of Glucosinolate Hydrolytic Products from Seeds of Eruca sativa (Mill.) Thell. Using GC‐MS
Authors: Arora Rohit , Sharma Deepika , Kumar Rakesh , Singh Bikram , Vig Adarsh P. , Arora Saroj
Published: September 2014

Glucosinolates and their hydrolytic products form an important class of plant secondary metabolites involved in various plant defense‐linked mechanisms. The successful isolation of particular glucosinolate hydrolytic products is limited by a number of factors like understanding the parent glucosinolate moiety, solubility, and stability under different drying conditions. The extraction protocols currently available were modified to achieve both an increased yield as well as an increased number of hydrolytic products. Eruca sativa (Mill.) Thell. (called arugula in the U.S.A.), a rich source of varied glucosinolates, was used for the standardization of different extraction protocols. We exploited the volatile nature of the glucosinolates and developed a method that not only enhanced the yield of glucosinolate hydrolytic products, but also reduced undesired compounds. Among all the tested protocols, hydrodistillation using Clevenger apparatus was judged as the best protocol, which was evident from an enhanced yield as well as an increased number of hydrolytic products when compared to the other methods as monitored by gas chromatography‐mass spectrometry.
The market for credit default swaps: new insights into investors' use of accounting information?
Authors: Griffin Paul A.
Published: September 2014

The market for credit default swaps has developed into a well‐functioning, global multi‐trillion dollar market, wherein investors price and transfer corporate financial instruments on the basis of credit risk. This paper first summarizes the structure and growth of the market. Next, I introduce theory and evidence on how investors price credits risk and explain how the quality of financial statement information plays a unique role in the determination of credit spread. I then review the nascent empirical accounting literature on this topic. This review sheds light on several accounting research questions that might be understood better in the setting of the credit default swap market. The final section summarizes suggestions for future work.
Tests of the effects of adolescent early alcohol exposures on adult outcomes
Authors: Irons Daniel E. , Iacono William G. , McGue Matt
Published: September 2014

Aims

To determine whether early adolescent alcohol use contributes to adult alcohol use, misuse and other adult substance‐related and social outcomes.

Design

In a longitudinal study of twins assessed at target ages 11, 14 and 24 years, two techniques adjusted for confounding factors: a propensity score (PS) adjusting for the effects of measured background covariates and co‐twin control (CTC) adjusting for confounding by unmeasured (including genetic) factors shared within early alcohol exposure‐discordant pairs.

Setting

The community‐based Minnesota Twin Family Study.

Participants

A total of 1512 (50.3% female) twins.

Measurements

Early adolescent alcohol exposures, adult substance‐related and social outcomes and background variables reflecting behavioral, familial and environmental characteristics.

Findings

Background covariates unbalanced between those with and without early alcohol exposure were balanced through PS‐based weighting, leaving several adult outcomes related to substance use or social functioning remaining significantly associated with early alcohol exposure. Similarly, the within‐pair individual‐level component of a CTC indicated that early alcohol‐exposed twins had higher risk than their non‐exposed co‐twins for several, but not all, of the same adult outcomes. For example, early alcohol use was associated with an adult index of alcohol use in both PS‐weighted (β = 0.57, P < 0.001) and CTC (β = 0.21, P = 0.031) analyses.

Conclusions

Early alcohol exposures predict adult alcohol problems and related outcomes, despite stringent adjustment for measured and non‐measured sources of potential confounding using propensity score and co‐twin control. Contrasting the methods indicated that exposure effect estimates from PS application were likely biased by unmeasured confounding factors.
Possibilities and considerations when merging dietary data from the world's two largest pregnancy cohorts: the Danish National Birth Cohort and the Norwegian Mother and Child Cohort Study
Authors: Olsen Sjurdur F. , Eva Birgisdottir Bryndis , Halldorsson Thorhallur I. , Brantsæter Anne Lise , Haugen Margaretha , Torjusen Hanne , Petersen Sesilje B. , Strøm Marin , Meltzer Helle Margrete
Published: September 2014

Objectives

To elucidate the research possibilities when merging data on maternal diet from the Danish National Birth Cohort (DNBC) and the Norwegian Mother and Child Cohort Study (MoBa), through comparison of (i) the methodology used for dietary assessment and (ii) the estimated intake of selected food groups in the two cohorts.

Design

Qualitative and quantitative comparison of the two dietary databases.

Setting

Two national prospective pregnancy cohorts.

Population

Denmark, Norway.

Methods

Comparison of food intake using food frequency questionnaires (FFQs).

Results

The FFQs had overlapping time windows and a majority of the questions in the two FFQs were comparable. Calculation principles shared similar features, including the software used and use of global questions to calibrate intakes of different food groups. A total of 63 food groups were defined that could be compared across the two cohorts; these were further aggregated down to 31 broader groups. A comparison of food intakes (grams/d) showed 39, 74 and 141% lower daily intakes of fish, potatoes and rice, respectively, in DNBC vs. MoBa and 39, 54 and 65% higher daily intakes of milk, butter and potatoes in DNBC vs. MoBa. For most other food groups, differences in consumption data were below 20%.

Conclusions

The two FFQs are to a large extent compatible and substantial differences in dietary habits were observed between the two cohorts. This may strengthen studies using pooled analysis to examine diet–disease relations. This is a conclusion of great importance given the colossal and costly task involved to establish each of these two cohorts.