bluuebunny/crossref_metadata_2025 huggingface dataset:
mRNA localization is linked to translation regulation in theCaenorhabditis elegansgerm lineage
Authors: Parker Dylan M. , Winkenbach Lindsay P. , Boyson Samuel P. , Saxton Matthew N. , Daidone Camryn , Al-Mazaydeh Zainab A. , Nishimura Marc T. , Mueller Florian , Osborne Nishimura Erin
Published: January 2020

Caenorhabditis elegansearly embryos generate cell-specific transcriptomes despite lacking active transcription. This presents an opportunity to study mechanisms of post-transcriptional regulatory control. In seeking the mechanisms behind this patterning, we discovered that some cell-specific mRNAs accumulate non-homogenously within cells, localizing to membranes, P granules (associated with progenitor germ cells in the P lineage), and P-bodies (associated with RNA processing). Transcripts differed in their dependence on 3’UTRs and RNA Binding Proteins, suggesting diverse regulatory mechanisms. Notably, we found strong but imperfect correlations between low translational status and P granule localization within the progenitor germ lineage. By uncoupling these, we untangled a long-standing question: Are mRNAs directed to P granules for translational repression or do they accumulate there as a downstream step? We found translational repression preceded P granule localization and could occur independent of it. Further, disruption of translation was sufficient to send homogenously distributed mRNAs to P granules. Overall, we show transcripts important for germline development are directed to P granules by translational repression, and this, in turn, directs their accumulation in the progenitor germ lineage where their repression can ultimately be relieved.

Maternally loaded mRNAs localize non-homogeneously withinC. elegansearly embryos correlating with their translational status and lineage-specific fates.
The neural computations for stimulus presence and modal identity diverge along a shared circuit
Authors: Tovar David A. , Noel Jean-Paul , Ishizawa Yumiko , Patel Shaun R. , Eskandar Emad N. , Wallace Mark T.
Published: January 2020

The brain is comprised of neural circuits that are able to flexibly represent the complexity of the external world. In accomplishing this feat, one of the first attributes the brain must code for is whether a stimulus is present and subsequently what sensory information that stimulus contains. One of the core characteristics of that information is which sensory modality(ies) are being represented. How information regarding both the presence and modal identity of a given stimulus is represented and transformed within the brain remains poorly understood. In this study, we investigated how the brain represents the presence and modal identity of a given stimulus while tactile, audio, and audio-tactile stimuli were passively presented to non-human primates. We recorded spiking activity from primary somatosensory (S1) and ventral pre-motor (PMv) cortices, two areas known to be instrumental in transforming sensory information into motor commands for action. Using multivariate analyses to decode stimulus presence and identity, we found that information regarding stimulus presence and modal identity were found in both S1 and PMv and extended beyond the duration of significant evoked spiking activity, and that this information followed different time-courses in these two areas. Further, we combined time-generalization decoding with cross-area decoding to demonstrate that while signaling the presence of a stimulus involves a feedforward-feedback coupling between S1-PMv, the processing of modal identity is largely restricted to S1. Together, these results highlight the differing spatiotemporal dynamics of information flow regarding stimulus presence and modal identity in two nodes of an important cortical sensorimotor circuit.

Significance Statement

It is unclear how the structure and function of the brain support differing sensory functions, such as detecting the presence of a stimulus in the environment vs. identifying it. Here, we used multivariate decoding methods on monkey neuronal data to track how information regarding stimulus presence and modal identity flow within a sensorimotor circuit. Results demonstrate that while neural patterns in both primary somatosensory (S1) and ventral pre-motor (PMv) cortices can be used to detect and discriminate between stimuli, they follow different time-courses. Importantly, findings suggest that while information regarding the presence of a stimulus flows reciprocally between S1 and PMv, information regarding stimulus identity is largely contained in S1.
A New Tree-Based Methodological Framework to Infer the Evolutionary History of Mesopolyploid Lineages: An Application to the Brassiceae Tribe (Brassicaceae)
Authors: Hénocq Laura , Gallina Sophie , Schmitt Eric , Castric Vincent , Vekemans Xavier , Poux Céline
Published: January 2020

Whole genome duplication events are notably widespread in plants and this poses particular challenges for phylogenetic inference in allopolyploid lineages, i.e. lineages that result from the merging of two or more diverged genomes after interspecific hybridization. The nuclear genomes resulting from allopolyploidization contain homologous gene copies from different evolutionary origins called homoeologs, whose orthologs must be sorted out in order to reconstruct the evolutionary history of polyploid clades. In this study, we propose a methodological approach to resolve the phylogeny of allopolyploid clades focusing on mesopolyploid genomes, which experienced some level of genome reshuffling and gene fractionation across their subgenomes. To illustrate our methodological framework we applied it to a clade belonging to the model Brassicaceae plant family, the Brassiceae tribe, that experienced a mesohexaploidy event. The dataset analysed consists of both publically available genomic sequences and new transcriptomic data according to taxa. The present methodology requires a well-annotated reference genome, for which the identification of the parental subgenome fragments has been performed (e.g. Brassica rapa and Brassica oleracea). Focusing on fully retained genes (i.e. genes for which all homoeologous gene copies inherited from the parental lineages are still present in the reference genome), the method constructs multi-labelled gene trees that allow subsequent assignment of each gene copy to its diploid parental lineage. Once the orthologous copies are identified, genes from the same parental origin are concatenated and tree-building methods are used to reconstruct the species tree. This method allows resolving the phylogenetic relationships (i) among extant species within a mesopolyploid clade, (ii) among the parental lineages of a mesopolyploid lineage, and (iii) between the parental lineages and closely related extant species. We report here the first well-resolved nuclear-based phylogeny of the Brassiceae tribe.
Identification of a novel breathing circuit that controls pain and anxiety
Authors: Liu Shijia , Ye Mao , Pao Gerald M. , Song Samuel Myeongsup , Jhang Jinho , Han Sung
Published: January 2020

Alleviating pain with controlled breathing has been practiced throughout human history. Despite its wide use and long history, a neural circuit-based understanding of the pain-breathing interaction is largely lacking. Here we report a novel breathing circuit that regulates non-homeostatic breathing rhythm, as well as pain and anxiety. We identify that a cluster of neurons expressing theOprm1gene, which encodes the μ-opioid receptor (MOR) in the lateral subdivision of parabrachial nucleus (PBLOprm1), directly regulates breathing rate in mice by conveying signals from the limbic areas to respiratory rhythm generating neurons in the medullary preBötzinger Complex (preBötC). In addition, we found that pain signals rapidly increase breathing rate by activating these neurons in both awake and anesthetized mice. Inactivating these neurons not only decreases the breathing rate, but it also substantially decreases anxiety-like behaviors and induces strong appetitive behaviors. Furthermore, PBLOprm1inactivation alleviates pain by attenuating the perception of the affective-motivational aspect of pain. These results suggest that PBLOprm1neurons play a critical role in the non-homeostatic regulation of breathing and in the regulation of pain and anxiety through breathing.
Quantifying the spatiotemporal dynamics of IRES versus Cap translation with single-molecule resolution in living cells
Authors: Koch Amanda , Aguilera Luis , Morisaki Tatsuya , Munsky Brian , Stasevich Timothy J.
Published: January 2020

Viruses use IRES sequences within their RNA to hijack translation machinery and thereby rapidly replicate in host cells. While this process has been extensively studied in bulk assays, the dynamics of hijacking at the single-molecule level remain unexplored in living cells. To achieve this, we developed a bicistronic biosensor encoding complementary repeat epitopes in two ORFs, one translated in a Cap-dependent manner and the other translated in an IRES-mediated manner. Using a pair of complementary probes that bind the epitopes co-translationally, our biosensor lights up in different colors depending on which ORF is being translated. In combination with single-molecule tracking and computational modeling, we measured the relative kinetics of Cap versus IRES translation and show: (1) Two non-overlapping ORFs can be simultaneously translated within a single mRNA; (2) EMCV IRES-mediated translation sites recruit ribosomes less efficiently than Cap-dependent translation sites but are otherwise nearly indistinguishable, having similar mobilities, sizes, spatial distributions, and ribosomal initiation and elongation rates; (3) Both Cap-dependent and IRES-mediated ribosomes tend to stretch out translation sites; (4) Although the IRES recruits two to three times fewer ribosomes than the Cap in normal conditions, the balance shifts dramatically in favor of the IRES during oxidative and ER stresses that mimic viral infection; and (5) Translation of the IRES is enhanced by translation of the Cap, demonstrating upstream translation can positively impact the downstream translation of a non-overlapping ORF. With the ability to simultaneously quantify two distinct translation mechanisms in physiologically relevant live-cell environments, we anticipate bicistronic biosensors like the one we developed here will become powerful new tools to dissect both canonical and non-canonical translation dynamics with single-molecule precision.

Graphical Abstract
Designing flow regimes to support entire river ecosystems
Authors: Tonkin Jonathan D. , Olden Julian D. , Merritt David. M. , Reynolds Lindsay V. , Rogosch Jane S. , Lytle David A.
Published: January 2020

Overcoming the challenges of water scarcity will require creative approaches to flow management and modeling approaches that forecast the effects of management actions on multiple ecosystem components simultaneously. Using a mechanistic multispecies modeling approach, we investigated the cross-ecosystem effects of environmental flow regimes designed for specific ecosystem outcomes. We reveal tradeoffs associated with flow regimes targeting riparian vegetation, fishes, and invertebrates. The different frequencies associated with each flow regime in some cases caused non-target ecosystem components to become locally extirpated within short (decadal) timespans. By incorporating multiple flow frequencies (from intraannual-scale pulses to large decadal-scale floods), the natural flow regime enabled a balanced but sub-optimal response of the three ecosystem components (mean 72% of designer flow). Although returning to a natural flow regime may not be possible in highly managed rivers, novel flow regimes must incorporate diverse frequencies inherent to such a regime and accommodate the sometimes conflicting requirements of different taxa at different times.
Cooperative and non-cooperative behaviour in the exploitation of a common renewable resource with environmental stochasticity
Authors: Hackney Michael , James Alex , Plank Michael J.
Published: January 2020

Classical fisheries biology aims to optimise fisheries-level outcomes, such as yield or profit, by controlling the fishing effort. This can be adjusted to allow for the effects of environmental stochasticity, or noise, in the population dynamics. However, when multiple fishing entities, which could represent countries, commercial organisations, or individual vessels, can autonomously determine their own fishing effort, the the optimal action for one fishing entity depends on the actions of others. Coupled with noise in the population dynamics, and with decisions about fishing effort made repeatedly, this becomes an iterated stochastic game. We tackle this problem using the tools of stochastic optimisation, first for the monopolist’s problem and then for the duopolist’s problem. In each case, we derive optimal policies that specify the best level of fishing effort for a given stock biomass. Under these optimal policies, we can calculate the equilibrium stock biomass, the expected long-term return from fishing and the probability of stock collapse. We also show that there is a threshold stock biomass below which it is optimal to stop fishing until the stock recovers. We then develop an agent-based model to test the effectiveness of simple strategies for responding to deviations by an opponent from a cooperative fishing level. Our results show that the economic value of the fishery to a monopolist, or to a consortium of fishing agents, is robust to a certain level of noise. However, without the means of making agreements about fishing effort, even low levels of noise make sustained cooperation between autonomous fishing agents difficult.
A possible physical mechanism of the torque generation of the bacterial flagellar motor
Authors: Chou Y. C.
Published: January 2020

The torque required for the rotation of the rotor of a bacterial flagellar motor (BFM) can be generated from an impulsive force resulting from the collision between the stator and the rotor. The asymmetry in the fluctuations of the tilting angle of the rotor determines the direction of rotation. The expressions of the torque and the step size can be derived from a Langevin equation of motion. The drag coefficient of BFM derived from the Langevin equation and the measured torque–speed (τ-ω) relation is notably high; the viscous force from the environment cannot account for it. The drag force may be caused by the frictional interaction between the bearing-like L- and P-rings of BFM and the cell membrane. Order-of-magnitude estimations of the torque and the step size are consistent with previous experimental observations. The slope of the linear dependence of the rotational frequency on the temperature was estimated and was consistent with the observed value. A simulation device having the structural characteristics of BFM was designed to demonstrate the applicability of the proposed mechanism. Many observations for the actual BFM, such as the bidirectional rotation and the τ-ω relations of the clockwise and counterclockwise rotations, were reproduced in the simulation experiments.

Importance

The concept that the torque required for the rotation of the rotor of a bacterial flagellar motor (BFM) can be generated from an impulsive force resulting from the collision between the stator and the rotor is new and effective. The magnitude of the torque and the size of the step derived from the proposed mechanism are consistent with the observed values. The torque-speed (τ-ω) relation might be explained by the frequency-dependent drag force caused by the frictional interaction between the bearing-like L- and P-rings of BFM and the cell membrane. The slope of the linear dependence of the rotational frequency on the temperature is consistent with the observed value, which has not been achieved previously.
Suppression of Cytotoxic T Cell Functions and Decreased Levels of Tissue Resident Memory T cell During H5N1 infection
Authors: Kandasamy Matheswaran , Furlong Kevin , Perez Jasmine T. , Manicassamy Santhakumar , Manicassamy Balaji
Published: January 2020

Seasonal influenza virus infections cause mild illness in healthy adults, as timely viral clearance is mediated by the functions of cytotoxic T cells. However, avian H5N1 influenza virus infections can result in prolonged and fatal illness across all age groups, which has been attributed to the overt and uncontrolled activation of host immune responses. Here we investigate how excessive innate immune responses to H5N1 impair subsequent adaptive T cell responses in the lungs. Using recombinant H1N1 and H5N1 strains sharing 6 internal genes, we demonstrate that H5N1 (2:6) infection in mice causes higher stimulation and increased migration of lung dendritic cells to the draining lymph nodes, resulting in higher numbers of virus specific T cells in the lungs. Despite robust T cell responses in the lungs, H5N1 (2:6) infected mice showed inefficient and delayed viral clearance as compared to H1N1 infected mice. In addition, we observed higher levels of inhibitory signals including increased PD1 and IL-10 expression by cytotoxic T cells in H5N1 (2:6) infected mice, suggesting that delayed viral clearance of H5N1 (2:6) was due to suppression of T cell functionsin vivo. Importantly, H5N1 (2:6) infected mice displayed decreased numbers of tissue resident memory T cells as compared to H1N1 infected mice; however, despite decreased number of tissue resident memory T cells, H5N1 (2:6) were protected against a heterologous challenge from H3N2 virus (X31). Taken together, our study provides mechanistic insight for the prolonged viral replication and protracted illness observed in H5N1 infected patients.

Importance

Influenza viruses cause upper respiratory tract infections in humans. In healthy adults, seasonal influenza virus infections result in mild disease. Occasionally, influenza viruses endemic in domestic birds can cause severe and fatal disease even in healthy individuals. In avian influenza virus infected patients, the host immune system is activated in an uncontrolled manner and is unable to control infection in a timely fashion. In this study, we investigated why the immune system fails to effectively control a modified form of avian influenza virus. Our studies show that T cell functions important for clearing virally infected cells are impaired by higher negative regulatory signals during modified avian influenza virus infection. In addition, memory T cell numbers were decreased in modified avian influenza virus infected mice. Our studies provide a possible mechanism for the severe and prolonged disease associated with avian influenza virus infections in humans.
Nanoscale Structure Determination of Murray Valley Encephalitis and Powassan Virus Non-coding RNAs
Authors: Mrozowich Tyler , Henrickson Amy , Demeler Borries , Patel Trushar R
Published: January 2020

Viral infections are responsible for numerous deaths worldwide. Flaviviruses, which contain RNA as their genetic material, are one of the most pathogenic families of viruses. There is an increasing amount of evidence suggesting that their 5’ and 3’ non-coding terminal regions are critical for their survival. In this study, the 5’ and 3’ terminal regions of Murray Valley Encephalitis and Powassan virus were examined using biophysical and computational modeling methods. First, the purity ofin-vitrotranscribed RNAs were investigated using size exclusion chromatography and analytical ultracentrifuge methods. Next, we employed small-angle X-ray scattering techniques to study solution conformation and low-resolution structures of these RNAs, which suggested that the 3’ terminal regions are highly extended, compared to the 5’ terminal regions for both viruses. Using computational modeling tools, we reconstructed 3-dimensional structures of each RNA fragment and compared them with derived small-angle X-ray scattering low-resolution structures. This approach allowed us to further reinforce that the 5’ terminal regions adopt more dynamic structures compared to the mainly double-stranded structures of the 3’ terminal regions.
The RING domain of mitochondrial E3 ubiquitin ligase 1 and its complex with Ube2D2: crystallization and X-ray diffraction
Authors: Lee Sang-Ok , Lee Chong-Kil , Ryu Kyoung-Seok , Chi Seung-Wook
Published: January 2020

Mitochondrial E3 ubiquitin ligase 1 (MUL1) is located in the mitochondrial outer membrane and regulates various biological processes, including apoptosis, cell growth, mitophagy and mitochondrial dynamics. The C-terminal region of MUL1 faces the cytoplasm and contains the RING domain (MUL1-RING) where the Ub~E2 thioester binds. Unlike most RING-type E3 enzymes, MUL1-RING alone does not have an additional region that recruits a substrate protein, yet is still able to ubiquitylate the substrate, the p53 protein. Nevertheless, the exact mechanism of the ubiquitylation of p53 by MUL1-RING has not yet been elucidated. In order to understand this novel ubiquitylation mechanism, it is necessary to determine the three-dimensional structures of MUL1-RING and of its complex with the cognate E2 enzyme. Here, Ube2D2 was validated as a functional E2 enzyme for the ubiquitylation of the p53 transactivation domain (p53-TAD) by MUL1-RING, and purification and crystallization processes for MUL1-RING and the MUL1-RING–Ube2D2 complex are reported.
Crystal structures of chlorido[dihydroxybis(1-iminoethoxy)]arsanido-κ3
N,As,N′]platinum(II) and of a polymorph of chlorido[dihydroxybis(1-iminopropoxy)arsanido-κ3
N,As,N′]platinum(II)
Authors: Marogoa Nina R. , Kama D.V. , Visser Hendrik G. , Schutte-Smith M.
Published: January 2020

Each central platinum(II) atom in the crystal structures of chlorido[dihydroxybis(1-iminoethoxy)arsanido-κ3
N,As,N′]platinum(II), [Pt(C4H10AsN2O4)Cl] (1), and of chlorido[dihydroxybis(1-iminopropoxy)arsanido-κ3
N,As,N′]platinum(II), [Pt(C6H14AsN2O4)Cl] (2), is coordinated by two nitrogen donor atoms, a chlorido ligand and to arsenic, which, in turn, is coordinated by two oxygen donor ligands, two hydroxyl ligands and the platinum(II) atom. The square-planar and trigonal–bipyramidal coordination environments around platinum and arsenic, respectively, are significantly distorted with the largest outliers being 173.90 (13) and 106.98 (14)° for platinum and arsenic in (1), and 173.20 (14)° and 94.20 (9)° for (2), respectively. One intramolecular and four classical intermolecular hydrogen-bonding interactions are observed in the crystal structure of (1), which give rise to an infinite three-dimensional network. A similar situation (one intramolecular and four classical intermolecular hydrogen-bonding interactions) is observed in the crystal structure of (2). Various π-interactions are present in (1) between the platinum(II) atom and the centroid of one of the five-membered rings formed by Pt, As, C, N, O with a distance of 3.7225 (7) Å, and between the centroids of five-membered (Pt, As, C, N, O) rings of neighbouring molecules with distances of 3.7456 (4) and 3.7960 (6) Å. Likewise, weak π-interactions are observed in (2) between the platinum(II) atom and the centroid of one of the five-membered rings formed by Pt, As, C, N, O with a distance of 3.8213 (2) Å, as well as between the Cl atom and the centroid of a symmetry-related five-membered ring with a distance of 3.8252 (12) Å. Differences between (2) and the reported polymorph [Miodragović et al. (2013). Angew. Chem. Int. Ed.
52, 10749–10752] are discussed.
N′-(2-Hydroxy-3-methoxybenzylidene)pyrazine-2-carbohydrazide monohydrate
Authors: Wang Zhaodong
Published: January 2020

In the title hydrated Schiff base, C13H12N4O3·H2O, the dihedral angle between the aromatic rings is 5.06 (11)° and an intramolecular O—H...N hydrogen bond closes an S(6) ring. In the crystal, Ow—H...O and Ow—H...N (w = water) hydrogen bonds link the components into centrosymmetric tetramers (two Schiff bases and two water molecules). Longer N—H...O hydrogen bonds link the tetramers into [010] chains. A weak C—H...O hydrogen bond and aromatic π–π stacking between the pyrazine and phenyl rings [centroid–centroid separations = 3.604 (2) and 3.715 (2) Å] are also observed.
Rethinking corruption on fiscal decentralization and global competitiveness Nexus
Authors: Chalil Tengku Munawar
Published: January 2020

Purpose

This study investigates the effects of fiscal decentralization on global competitiveness through the level of corruption. This study aims to clarify the causal impacts of fiscal decentralization policy on the achievement of competitiveness rank considering the degree of corruption in a country.

Design/methodology/approach

The paper uses an empirical study using both cross-country arithmetic mean and panel data, covering ten-year period (2005-2014). The analysis uses both linear and non-linear specification in search of actual intermediating effects of corruption with controlling the possible endogeneity.

Findings

The paper provides empirical insights about corruption effects of fiscal decentralization on global competitiveness. It suggests that increasing level of fiscal decentralization has a positive contribution to competitiveness for the less-corrupt countries. The adverse effects appear for corrupt countries where the delegation of fiscal authority should endanger the country competitiveness.

Research limitations/implications

This research exploits the well-known measurement of fiscal decentralization, the degree of corruption and competitiveness. Therefore, this measurement might be challenged for representing the real concept of decentralization, corruption and competitiveness, furthermore its relationship. Despite the limitation, this research explores the entanglement of fiscal decentralization, corruption and competitiveness.

Practical implications

The paper provides the implications for the national policymakers about decentralizing the fiscal authority to achieve higher competitiveness level, through assessing their state of corruption.

Originality/value

The research provides additional comments for Oates’ (1972) decentralization theorem in connection to competitiveness, by adding corruption level as pre-requisite condition.
Management approach for innovation success in unstable and stable environments
Authors: Abidi Dora , Koichi Nakagawa
Published: January 2020

Purpose

This paper aims to examine the management approaches that play a key role for innovation success in a stable and unstable environment.

Design/methodology/approach

Tunisia and Japan were chosen as a research sites to assess the accuracy of management approach adopted in each environment. Japan, as a developed, stable and predictable market, involves a traditional/conventional management mode known as administrative control approach (ACA) for successful innovation. However, we argue that a developing country is characterized by its unstable environment and requires an opportunity-based approach (OBA) that lies in the firm’s openness to search and benefit from environmental opportunities.

Findings

The paper confirms that OBA improves product innovation success in an unstable environment, for innovation in a stable one.

Originality/value

The paper provides a comprehensive comparison between innovation driven management approaches towards stable and unstable environments through multi-group structural equation modeling.
Managing technological innovation in the sports industry: a challenge for retail management
Authors: Vrontis Demetris , Viassone Milena , Serravalle Francesca , Christofi Michael
Published: January 2020

Purpose

The purpose of this paper is twofold: first, to investigate the effects of the digitalization process on the demand and supply side in the sports world through the advent of mobile apps and online services, such as YouTube, which provide free (or almost) real fitness courses; and second, to investigate how technological innovation is managed in the sports sector.

Design/methodology/approach

Drawing on a survey research approach, this study collected 150 questionnaires from consumers in the North of Italy.

Findings

Based on a descriptive analysis of the data, the findings show that the digital channel becomes significant at an exponential rate and takes on a leading role in today’s era, especially among young people. However, the results also show that the traditional channel of use of the sports service (gyms/fitness centers) is privileged by consumers under the age of 35, even though there is a weak penetration of innovative tools offered by the innovation technology (mobile app and video tutorials on social networks such as YouTube) in the sports sector.

Practical implications

The study provides an exhaustive overview of academic literature on technology and innovation management, and provides the contact point between the physical and digital world in the sports sector, and adds a significant scholarly and practical value in the exercise at home perspective of consumers. This research also contributes to the discussion on the competitiveness between the two channels (physical and digital one) in the sports sector, thus giving rise to further research concerning the offer of the type of sports service.

Originality/value

This study is among the few that connect the technological advancements and management within the sports industry and provides the ground and theoretical basis for the scholar community to further build on.
The fit of competitive strategies and firm-specific advantages with country-specific advantages in explaining manufacturing location choices
Authors: Akpinar Murat
Published: January 2020

Purpose

This paper aims to clarify the fit of competitive strategies and firm-specific advantages (FSAs) with country-specific advantages (CSAs) in explaining manufacturing location choices at product category level in the European automotive industry.

Design/methodology/approach

Seven hypotheses are formulated and tested using binomial logistic regression with data from 148 passenger car models (i.e. product category level) that are sold in Europe and manufactured in countries that offer CSAs of either cost advantages or differentiation advantages. The first four hypotheses test manufacturing location choices of product categories pursuing cost leadership strategy, differentiation strategy, focus strategy and hybrid strategy. The other three hypotheses test whether FSAs of R&D capability, marketing capability and operations capability will impact on the manufacturing location choice. The tests control for the type of passenger cars as well as the manufacturer’s region of origin.

Findings

While pursuing cost leadership strategy leads to manufacturing in countries that offer cost advantages, pursuing differentiation strategy as well as strong R&D capability and marketing capability result in manufacturing in countries that offer differentiation advantages. Focus strategy, hybrid strategy and operations capability do not have an impact on the manufacturing location choice at product category level.

Research limitations/implications

Conducting empirical research at product category level is subject to limitations in the choices of FSAs due to lack of availability of data.

Practical implications

Managers should assess the competitive strategies and FSAs of their product categories and then decide about manufacturing locations based on their fit with host country CSAs. Policymakers should understand the CSAs of their countries and target to attract manufacturing FDI from product categories with matching competitive strategies and FSAs.

Originality/value

The research contributes to discussions in explaining manufacturing location choices. Its originality lies in being the first study to test the fit of competitive strategies and FSAs of product categories with CSAs.
Solution for free vibration of spatial curved beams
Authors: Wang Guangxin , Zhu Lili , Higuchi Ken , Fan Wenzhong , Li Linjie
Published: January 2020

Purpose

The purpose of this paper is to propose and analyze the free vibration response of the spatial curved beams with variable curvature, torsion and cross section, in which all the effects of rotary inertia, shear and axial deformations can be considered.

Design/methodology/approach

The governing equations for free vibration response of the spatial curved beams are derived in matrix formats, considering the variable curvature, torsion and cross section. Frobenius’ scheme and the dynamic stiffness method are applied to solve these equations. A computer program is coded in Mathematica according to the proposed method.

Findings

To assess the validity of the proposed solution, a convergence study is carried out on a cylindrical helical spring with a variable circular cross section, and a comparison is made with the finite element method (FEM) results in ABAQUS. Further, the present model is used for reciprocal spiral rods with variable circular cross section in different boundary conditions, and the comparison with FEM results shows that only a limited number of terms in the results provide a relatively accurate solution.

Originality/value

The numerical results show that only a limited number of terms are needed in series solutions and in the Taylor expansion series to ensure an accurate solution. In addition, with a simple modification, the present formulation is easy to extend to analyze a more complicated model by combining with finite element solutions or analyze the transient responses and stochastic responses of spatial curved beams by Laplace transformation or Fourier transformation.
Rapid multi-objective optimization of antennas using nested kriging surrogates and single-fidelity EM simulation models
Authors: Koziel Slawomir , Pietrenko-Dabrowska Anna
Published: January 2020

Purpose

This study aims to propose a computationally efficient framework for multi-objective optimization (MO) of antennas involving nested kriging modeling technology. The technique is demonstrated through a two-objective optimization of a planar Yagi antenna and three-objective design of a compact wideband antenna.

Design/methodology/approach

The keystone of the proposed approach is the usage of recently introduced nested kriging modeling for identifying the design space region containing the Pareto front and constructing fast surrogate model for the MO algorithm. Surrogate-assisted design refinement is applied to improve the accuracy of Pareto set determination. Consequently, the Pareto set is obtained cost-efficiently, even though the optimization process uses solely high-fidelity electromagnetic (EM) analysis.

Findings

The optimization cost is dramatically reduced for the proposed framework as compared to other state-of-the-art frameworks. The initial Pareto set is identified more precisely (its span is wider and of better quality), which is a result of a considerably smaller domain of the nested kriging model and better predictive power of the surrogate.

Research limitations/implications

The proposed technique can be generalized to accommodate low- and high-fidelity EM simulations in a straightforward manner. The future work will incorporate variable-fidelity simulations to further reduce the cost of the training data acquisition.

Originality/value

The fast MO optimization procedure with the use of the nested kriging modeling technology for approximation of the Pareto set has been proposed and its superiority over state-of-the-art surrogate-assisted procedures has been proved. To the best of the authors’ knowledge, this approach to multi-objective antenna optimization is novel and enables obtaining optimal designs cost-effectively even in relatively high-dimensional spaces (considering typical antenna design setups) within wide parameter ranges.
Effect of groove shape on the hydrodynamic lubrication of journal bearing considering cavitation
Authors: Chen Yu , Feng Jun , Sun Y. , Peng Xu , Dai Qiao , Yu Chengtao
Published: January 2020

Purpose

The purpose of this study is to investigate the influence of groove shape on the hydrodynamic characteristics of a journal bearing.

Design/methodology/approach

The computational fluid dynamics model also takes into account the cavitation phenomena and thermal effect, which can illustrate the lubrication performance of a journal bearing.

Findings

The hydrodynamic simulations of the journal bearing with the different groove shapes are conducted under different operation conditions.

Originality/value

Based on the numerical analysis, the suggestions are presented for groove shape selection and can be used to the design of a journal bearing under the extreme operation condition.
Analysis of the predictive effect and feedback control in an extended lattice hydrodynamic model
Authors: Li Lixiang , Ge Hongxia , Cheng Rongjun
Published: January 2020

Purpose

This paper aims to put forward an extended lattice hydrodynamic model, explore its effects on alleviating traffic congestion and provide theoretical basis for traffic management departments and traffic engineering implementation departments.

Design/methodology/approach

The control method is applied to study the stability of the new model. Through nonlinear analysis, the mKdV equation representing kink-antikink soliton is acquired.

Findings

The predictive effect and the control signal can enhance the traffic flow stability and reduce the energy consumption.

Originality/value

The predictive effect and feedback control are first considered in lattice hydrodynamic model simultaneously. Numerical simulations demonstrate that these two factors can enhance the traffic flow stability.
Measuring book impact via content-level academic review mining
Authors: Zhou Qingqing , Zhang Chengzhi
Published: January 2020

Purpose

As for academic papers, the customary methods for assessing the impact of books are based on citations, which is straightforward but limited to the coverage of databases. Alternative metrics can be used to avoid such limitations, such as blog citations and library holdings. However, content-level information is generally ignored, thus overlooking users’ intentions. Meanwhile, abundant academic reviews express scholars’ opinions on books, which can be used to assess books’ impact via fine-grained review mining. Hence, this study aims to assess books’ use impacts by conducting content mining of academic reviews automatically and thereby confirmed the usefulness of academic reviews to libraries and readers.

Design/methodology/approach

Firstly, 61,933 academic reviews in Choice: Current Reviews for Academic Libraries were collected with three metadata metrics. Then, review contents were mined to obtain content metrics. Finally, to identify the reliability of academic reviews, Choice review metrics and other assessment metrics for use impact were compared and analysed.

Findings

The analysis results reveal that fine-grained mining of academic reviews can help users quickly understand multi-dimensional features of books, judge or predict the impacts of mass books, so as to provide references for different types of users (e.g. libraries and public readers) in book selection.

Originality/value

Book impact assessment via content mining can provide more detail information for massive users and cover shortcomings of traditional methods. It provides a new perspective and method for researches on use impact assessment. Moreover, this study’s proposed method might also be a means by which to measure other publications besides books.
Sunshine, temperature and wind
Authors: File Dramani J.M. , Derbile Emmanuel Kanchebe
Published: January 2020

Purpose

This paper aims to draw on community risk assessment (CRA) for assessing vulnerability to climate change in north-western Ghana, focusing on sunshine, temperature and wind, elements of climate which are seldom explored in vulnerability assessments to climate change.

Design/methodology/approach

The paper draws on data collected from a qualitative research design that used participatory rural appraisal methods, particularly, in-depth interviews, focus group discussions and seasonal calendar analysis in three selected rural communities of the Sissala East District. Furthermore, an inter-generational framework was adopted for comparative assessment of vulnerability and changes in vulnerability to climate change.

Findings

The results show that the current generation of smallholder farmers is more vulnerable to climate change than the past generation, the era of grandparents. Thus, farmers are exposed to higher-intensity sunshine, temperature and wind in contemporary times than was the case in the past. Consequently, their livelihoods are affected the most by the damaging effects of these climatic hazards. The CRA process revealed the relevance of indigenous knowledge systems for vulnerability assessments and at the same time, underpins the need for adaptation of such knowledge if it is to sustain smallholder farmer efforts at climate change adaptation at community levels.

Practical implications

The paper recommends an endogenous development approach to climate change adaptation planning (CCAP), one that will build on indigenous knowledge systems for effective community education, mobilization and participatory response to climate change. Policy interventions should aim at enhancing climate change adaptation through innovations in soil and water conservation, access to water for irrigation and domestic use, climate smart-housing architecture and agro-forestry within the framework of decentralization and district development planning.

Originality/value

This paper will contribute to climate change research in two ways: first, by drawing attention to the usefulness of CRA in vulnerability assessment; and second, by focusing on climate elements which are critical for CCAP but rarely given sufficient attention in vulnerability assessments.
The pathology of housing policies in Iran: a criterion-based analysis
Authors: Zarghamfard Moslem , Meshkini Abolfazl , Pourahmad Ahmad , Murgante Beniamino
Published: January 2020

Purpose

Housing policy is a key tool in urban development and has multiple functions that directly affect human welfare. This study aims to review housing policies in Iran from a critical perspective. In fact, the study and pathology of housing policies are considered in this research.

Design/methodology/approach

To advance this research, a quantitative (fuzzy TOPSIS and fuzzy AHP) method was used to rank the policies and the qualitative method (interview and literature review) was used for the pathology of housing policies.

Findings

The failure of policies to provide housing in Iran is decisive, but social housing policy has a relative superiority to other policies. Causes of failure of Iranian housing policies are as follows in a pathological perspective: commodification and speculative approach to housing; lake of social and physical sustainability; social stratification and classification; inconsistency with environmental conditions; non-indigenous nature of housing policies; exclusion of local institutions in the decision-making process; and the dominance of a populist perspective on housing.

Originality/value

This study is a comprehensive study because it has been extracted from the dissertation. By reading this study, the reader will be aware of the general conditions of the Iranian housing sector.
Supply chain lead time reduction in a pharmaceutical production warehouse – a case study
Authors: Abideen Ahmed Zainul , Mohamad Fazeeda Binti
Published: January 2020

Purpose

The purpose of this study is to apply value stream mapping (VSM) in Malaysian pharmaceutical production warehouse. A current and future state value stream map from the raw material receiving end to the production unit was developed to find out waste and unwanted lead time. It was very much essential to cut down the supply chain lead time at the initial phase as the raw material unloading, sorting, temporary storage and dispatch to production were seen contributing to a huge lead time build-up.

Design/methodology/approach

The study was initiated with the selection of a product family, construction of the current state map, identification of various wastes and the development of future state map.

Findings

The expected outcomes of the study include the quantification of wastes, improvement in value-added percentage and lead time reduction.

Research limitations/implications

The study was carried out in a single pharmaceutical company. The results of the study are deployable and can be functional in similar production organizations. Contrary to common VSMs that capture core production processes, this study provides strong insights that shall help design lean supply chains, especially in the pharmaceutical domain. This paper has also addressed the viability of the lean in the pharmaceutical warehouse and the reduction in lead time to improve demand forecasting, marketing and sales.

Practical implications

The results of this study have indicated that a significant reduction in pharmaceutical warehouse supply chain lead time is possible as a result of the implementation of VSM from the supply chain’s perspective.

Social implications

The insights from this study help in understanding the pharmaceutical supply chain risks and their outcomes.

Originality/value

The paper reports a real-time study conducted in a warehouse of a pharmaceutical organization. Hence, the contributions are original.
An empirical study into the limitations and emerging trends of Six Sigma in manufacturing and service organisations
Authors: Antony Jiju , Sony Michael
Published: January 2020

Purpose

The purpose of this paper is to carry out an empirical study of the limitations and emerging trends of Six Sigma in manufacturing and service companies.

Design/methodology/approach

The authors developed an online survey instrument based on the existing literature addressing the current limitations and emerging trends of Six Sigma in manufacturing and service companies. In this study, 75 Six Sigma Master Black Belts, 39 Black Belts and 12 Green Belts from large manufacturing and service companies participated; each of whom is familiar with the Six Sigma topics.

Findings

This study reports the top 5 limitations and emerging trends of Six Sigma from the viewpoints of subject matter experts from large manufacturing and service companies from over 20 countries. The main finding is that the top 4 limitations were identical for both manufacturing and service companies. These limitations include: the integration of Six Sigma with Big Data, the use of Six Sigma in small medium and micro-enterprises, an over emphasis of Six Sigma on variability reduction and the poor implementation of Six Sigma and its resultant negative impact on employee satisfaction.

Practical implications

In order to sustain Six Sigma initiatives in organisations, the authors argue that the limitations and emerging trends of this powerful business strategy should be understood and appropriate remedial strategies developed to address said limitations.

Originality/value

To the best of the authors’ knowledge, this is the first empirical study to examine the limitations and emerging trends of Six Sigma in both manufacturing and service organisations. Moreover, the findings of the study can be very beneficial to many organisations.