bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-read amplicon denoising
Authors: Kumar Venkatesh , Vollbrecht Thomas , Chernyshev Mark , Mohan Sanjay , Hanst Brian , Bavafa Nicholas , Lorenzo Antonia , Ketteringham Robert , Eren Kemal , Golden Michael , Oliveira Michelli Faria , Murrell Ben
Published: August 2018

Long-read next generation amplicon sequencing shows promise for studying complete genes or genomes from complex and diverse populations. Current long-read sequencing technologies have challenging error profiles, hindering data processing and incorporation into downstream analyses. Here we consider the problem of how to reconstruct, free of sequencing error, the true sequence variants and their associated frequencies. Called “amplicon denoising”, this problem has been extensively studied for short-read sequencing technologies, but current solutions do not appear to generalize well to long reads with high indel error rates. We introduce two methods: one that runs nearly instantly and is very accurate for medium length reads (here ~2.6kb) and high template coverage, and another, slower method that is more robust when reads are very long or coverage is lower.

On one real dataset with ground truth, and on a number of simulated datasets, we compare our two approaches to each other and to existing algorithms. We outperform all tested methods in accuracy, with competitive run times even for our slower method.

Fast Amplicon Denoising (FAD) and Robust Amplicon Denoising (RAD) are implemented purely in the Julia scientific computing language, and are hereby released along with a complete toolkit of functions that allow long-read amplicon sequence analysis pipelines to be constructed in pure Julia. Further, we make available a webserver to dramatically simplify the processing of long-read PacBio sequences.
Kinetic Pathways of Topology Simplification by Type-II Topoisomerases in Knotted Supercoiled DNA
Authors: Ziraldo Riccardo , Hanke Andreas , Levene Stephen D.
Published: August 2018

The topological state of covalently closed, double-stranded DNA is defined by the knot typeKand the linking-number difference ΔLkrelative to unknotted relaxed DNA. DNA topoisomerases are essential enzymes that control the topology of DNA in all cells. In particular, type-II topoisomerases change bothKand ΔLkby a duplex-strand-passage mechanism and have been shown to simplify the topology of DNA to levels below thermal equilibrium at the expense of ATP hydrolysis. It remains a puzzle how small enzymes are able to preferentially select strand passages that result in topology simplification in much larger DNA molecules. Using numerical simulations, we consider the non-equilibrium dynamics of transitions between topological states (K, ΔLk) in DNA induced by type-II topoisomerases. For a biological process that delivers DNA molecules in a given topological state (K,ΔLk) at a constant rate we fully characterize the pathways of topology simplification by type-II topoisomerases in terms of stationary probability distributions and probability currents on the network of topological states (K,ΔLk). In particular, we observe that type-II topoisomerase activity is significantly enhanced in DNA molecules that maintain a supercoiled state with constant torsional tension. This is relevant for bacterial cells in which torsional tension is maintained by enzyme-dependent homeostatic mechanisms such as DNA-gyrase activity.
Insight into the genetic architecture of back pain and its risk factors from a study of 509,000 individuals
Authors: Freidin Maxim B , Tsepilov Yakov A , Palmer Melody , Karssen Lennart C ,   CHARGE Musculoskeletal Working Group, Suri Pradeep , Aulchenko Yurii S , Williams Frances MK
Published: August 2018

Back pain (BP) is a common condition of major social importance and poorly understood pathogenesis. Combining data from the UK Biobank and CHARGE consortium cohorts allowed us to perform a very large GWAS (total N = 509,070) and examine the genetic correlation and pleiotropy between BP and its clinical and psychosocial risk factors. We identified and replicated three BP associated loci, including one novel region implicating SPOCK2/CHST3 genes. We provide evidence for pleiotropic effects of genetic factors underlying BP, height, and intervertebral disc problems. We also identified independent genetic correlations between BP and depression symptoms, neuroticism, sleep disturbance, overweight, and smoking. A significant enrichment for genes involved in central nervous system and skeletal tissue development was observed. The study of pleiotropy and genetic correlations, supported by the pathway analysis, suggests at least two strong molecular axes of BP genesis, one related to structural/anatomic factors such as intervertebral disk problems and anthropometrics; and another related to the psychological component of pain perception and pain processing. These findings corroborate with the current biopsychosocial model as a paradigm for BP. Overall, the results demonstrate BP to have an extremely complex genetic architecture that overlaps with the genetic predisposition to its biopsychosocial risk factors. The work sheds light on pathways of relevance in the prevention and management of LBP.
Interferon-alpha2 but not Interferon-gamma serum levels are associated with intramuscular fat in obese patients with nonalcoholic fatty liver disease
Authors: Tarantino Giovanni , Costantini Susan , Citro Vincenzo , Conforti Paolo , Capone Francesca , Sorice Angela , Capone Domenico
Published: August 2018

Background

Intramuscular triglycerides (IMTGs) represent an important energy supply and a dynamic fat-storage depot that can expand during periods of elevated lipid availability and a fatty ac-id source. Ultrasonography (US) of human skeletal muscles is a practical and reproducible method to assess both IMTG presence and entity.

Although a crosstalk between cytokines in skeletal muscle and adipose tissue has been suggested in obesity, condition leading to hepatic steatosis (HS) or better defined as nonalcoholic fatty liver disease and cancer, there are still questions to be answered about the role of interferons (IFNs), alpha as well as gamma, and IMTG in obesity. We aimed at discovering any correlation between IFNs and IMTG.

Methods

We analysed anthropometric data, metabolic parameters and imaging features of a population of obese subjects with low-prevalence of co-morbidities but HS. The levels of serum IFNs were detected by a magnetic bead-based multiplex immunoassays.

Results

Serum concentrations of IFN-alpha2 were increased, while serum levels of IFN-gamma were decreased confronted with those of controls; the severity of IMTG, revealed at US as Heckmatt scores, was inversely predicted by IFN-alpha2 serum concentrations; IMTG scores were not predicted by serum levels of IFN-gamma; IMTG scores were predicted by HS severity, ascertained at US; HS severity was predicted by visceral adipose tissue, assessed by US, but the latter was not instrumental to IMTG.

Discussion & Conclusion

This study has added some pieces of observation about the cytokine network regulating the interplay between IMTG and obesity in obese patients with HS.
Single-nucleus RNA sequencing shows convergent evidence from different cell types for altered synaptic plasticity in major depressive disorder
Authors: Nagy Corina , Maitra Malosree , Tanti Arnaud , Suderman Matthew , Théroux Jean-Francois , Mechawar Naguib , Ragoussis Jiannis , Turecki Gustavo
Published: August 2018

Major depressive disorder (MDD) is a complex illness that involves the interaction of different brain systems, pathways, and cell types. Past molecular studies of MDD relied on cellular homogenates of post-mortem brain tissue, making it impossible to determine gene expression changes within individual cells. Using single-cell transcriptomics, we examined almost 80,000 nuclei from the dorsolateral prefrontal cortex of individuals with MDD and healthy controls. Our analyses identified 26 distinct cellular clusters, and over 60% of these showed transcriptional differences between groups. Specifically, 96 genes were differentially expressed, the majority of which were downregulated. Convergent evidence from our analyses, including gene expression, differential correlation, and gene ontology implicated dysregulation of synaptic plasticity in the etiopathogenesis of MDD. Our results show that this high-resolution approach can reveal previously undetectable changes in specific cell types in the context of complex phenotypes and heterogeneous tissues.
RNA-seq reveals few differences in resistant and susceptible responses of barley to infection by the spot blotch pathogenBipolaris sorokiniana
Authors: Haas Matthew , Mascher Martin , Castell-Miller Claudia , Steffenson Brian J.
Published: August 2018

Spot blotch, caused byBipolaris sorokiniana(Sacc.) Shoem., is an economically important disease affecting barley (Hordeum vulgareL.). The disease has largely been controlled in the Upper Midwest region of the USA through a suite of quantitative trait loci (QTL) termed the Midwest Six-rowed Durable Resistance Haplotype (MSDRH). These QTL have been bred into all six-rowed Midwest barley cultivars, including the widely used cultivar Morex. We identified a gamma ray- induced Morex mutant (MUT) that exhibits spot blotch susceptibility at the seedling stage. This mutant also spontaneously develops extremely large necrotic lesions in the absence of the pathogen at the adult plant stage. Spot blotch susceptibility at the seedling stage and necrotic lesion formation at the adult plant stage are highly correlated. To start dissecting the molecular responses underlying the observed symptoms at the seedling stage, we conducted a time course RNA-seq experiment comparing the wild type (WT) and the mutant (MUT) Morex at 12, 24 and 36 h afterB. sorokinianainoculation. Mock-inoculated controls were also included. A total of 10,772 and 11,530 genes were differentially expressed between treatments for WT and MUT genotypes, respectively, while 277 and 195 genes were differentially expressed between fungal and mock-inoculated genotypes, respectively. The transcript expression profiles of WT and MUT Morex samples were similar for most treatments. Two genes whose expression was putatively knocked out in the MUT were identified: HORVU3Hr1G019920 (glycine-rich protein) and HORVU5Hr1G120850 (Long- chain-fatty-acid—CoA ligase 1). The latter appears to be genetically intact, but not expressed. Collectively, these data suggest that MUT susceptibility toB. sorokinianais a result of minor, rather than major, differences in the defense responses.
A Bayesian Approach to Beam-Induced Motion Correction in Cryo-EM Single-Particle Analysis
Authors: Zivanov Jasenko , Nakane Takanori , Scheres Sjors H. W.
Published: August 2018

We present a new method to estimate the trajectories of particle motion and the amount of cumulative beam damage in electron cryo-microscopy (cryo-EM) single particle analysis. We model the motion within the sample through the use of Gaussian Process regression. This allows us to associate with each hypothetical set of particle trajectories a prior likelihood that favours spatially and temporally smooth motion without imposing hard constraints. This formulation enables us to express the a-posteriori likelihood of a set of particle trajectories as a product of that prior likelihood and an observation likelihood given by the data, and to then maximise this a-posteriori likelihood. Since our smoothness prior requires three parameters that describe the statistics of the observed motion, we also propose an efficient stochastic method to estimate those parameters. Finally, we propose a practical means of estimating the average amount of cumulative radiation damage as a function of radiation dose and spatial frequency, and a robust method of fitting relative B-factors to it. We evaluate our method on three publicly available datasets, and illustrate its usefulness by comparison with state-of-the-art methods and previously published results. The new method has been implemented as Bayesian polishing in RELION-3, where it replaces the existing particle polishing method, as it outperforms the latter in all tests conducted.
bayNorm: Bayesian gene expression recovery, imputation and normalisation for single cell RNA-sequencing data
Authors: Tang Wenhao , Bertaux François , Thomas Philipp , Stefanelli Claire , Saint Malika , Marguerat Samuel , Shahrezaei Vahid
Published: August 2018

Normalisation of single cell RNA sequencing (scRNA-seq) data is a prerequisite to their interpretation. The marked technical variability and high amounts of missing observations typical of scRNA-seq datasets make this task particularly challenging. Here, we introduce bayNorm, a novel Bayesian approach for scaling and inference of scRNA-seq counts. The method’s likelihood function follows a binomial model of mRNA capture, while priors are estimated from expression values across cells using an empirical Bayes approach. We demonstrate using publicly-available scRNA-seq datasets and simulated expression data that bayNorm allows robust imputation of missing values generating realistic transcript distributions that match single molecule FISH measurements. Moreover, by using priors informed by dataset structures, bayNorm improves accuracy and sensitivity of differential expression analysis and reduces batch effect compared to other existing methods. Altogether, bayNorm provides an efficient, integrated solution for global scaling normalisation, imputation and true count recovery of gene expression measurements from scRNA-seq data.
Hypoxia-induced switch in SNAT2/SLC38A2 regulation generates endocrine-resistance in breast cancer
Authors: Morotti Matteo , Bridges Esther , Valli Alessandro , Choudhry Hani , Sheldon Helen , Wigfield Simon , Gray Nicki , Jones Dylan , Teoh Eugene J. , Cheng Wei-Chen , Lord Simon , Haider Syed , McIntyre Alan , Goberdhan Deborah C. I. , Buffa Francesca , Harris Adrian L.
Published: August 2018

Tumor hypoxia is associated with poor patient outcomes in estrogen receptor-α (ERα) positive breast cancer. Hypoxia is known to affect tumor growth by reprogramming metabolism and regulating amino acid (AA) uptake. Here we show that the glutamine transporter, SNAT2, is the AA transporter most frequently induced by hypoxia in breast cancer and it is regulated by HIF1α bothin-vitroandin-vivoin xenografts. SNAT2 induction in MCF7 cells was also regulated by ERα but it became predominantly a HIF-1α-dependent gene under hypoxia. Relevant to this, binding sites for both HIF-1α and ERα overlap in SNAT2’s cis-regulatory elements. In addition, the downregulation of SNAT2 by the ER antagonist fulvestrant was reverted in hypoxia.

Overexpression of SNAT2in-vitroto recapitulate the levels induced by hypoxia caused enhanced growth, particularly after ERα inhibition, in hypoxia, or when glutamine levels were low. SNAT2 upregulationin-vivocaused complete resistance to anti-estrogen and, partially, anti-VEGF therapies. Finally, high SNAT2 expression levels correlate with HIF-1α and worse outcome in patients given anti-estrogen therapy. Our findings show a switch in regulation of SNAT2 between ERα and HIF-1α, leading to endocrine resistance in hypoxia. Development of drugs targeting SNAT2 may be of value for a subset of hormone-resistant breast cancer.
Genome-wide identification and functional analysis of circRNAs in Zea mays
Authors: Tang Baihua , Hao Zhiqiang , Zhu Yanfeng , Zhang Hua , Li Guanglin
Published: August 2018

Circular RNAs (circRNAs) are a class of endogenous noncoding RNAs, which increasingly drawn researchers’ attention in recent years as their importance in regulating gene expression at the transcriptional and post-transcriptional levels. With the development of high-throughput sequencing and bioinformatics, circRNAs have been widely analysed in animals, but the understanding of characteristics and function of circRNAs is limited in plants, especially in maize. Here, 3715 unique circRNAs were predicted in Zea mays systematically, and 8 of 12 circRNAs were validated by experiments. By analysing circRNA sequence, the events of alternative circularization phenomenon were found prevailed in maize. By comparing circRNAs in different species, it showed that part circRNAs are conserved across species, for example, there are 273 circRNAs conserved between maize and rice. Although most of the circRNAs have low expression levels, we found 213 differential expressed circRNAs responding to heat, cold, or drought, and 1782 tissue-specific expressed circRNAs. The results showed that those circRNAs may have potential biological functions in specific situations. Finally, two different methods were used to search circRNA functions, which were based on circRNAs originated from protein-coding genes and circRNAs as miRNA decoys. 346 circRNAs could act as miRNA decoys, which might modulate the effects of multiple molecular functions, including binding, catalytic activity, oxidoreductase activity, and transmembrane transporter activity. Maize circRNAs were identified, classified and characterized systematically. We also explored circRNA functions, suggesting that circRNAs are involved in multiple molecular processes and play important roles in regulating of gene expression. Our results provide a rich resource for further study of maize circRNAs.
Biodynamics: A novel quasi-first principles theory on the fundamental mechanisms of cellular function/dysfunction and the pharmacological modulation thereof
Authors: Selvaggio Gianluca , Pearlstein Robert A
Published: August 2018

Cellular function depends on heterogeneousdynamicintra-, inter-, and supramolecular structure-function relationships. However, the specific mechanisms by which cellular function is transduced from molecular systems, and by which cellular dysfunction arises from molecular dysfunction are poorly understood. We proposed previously that cellular function manifests as a molecular form of analog computing, in which specific time-dependent state transition fluxes within sets of molecular species (“molecular differential equations” (MDEs)) are sped and slowed in response to specific perturbations (inputs). In this work, we offer a theoretical treatment of the molecular mechanisms underlying cellular analog computing (which we refer to as “biodynamics”), focusing primarily on non-equilibrium (dynamic) intermolecular state transitions that serve as the principal means by which MDE systems are solved (the molecular equivalent of mathematical “integration”). Under these conditions, bound state occupancy is governed bykonandkoff, together with the rates of binding partner buildup and decay. Achieving constant fractional occupancy over time depends on: 1) equivalence between konand the rate of binding site buildup); 2) equivalence betweenkoffand the rate of binding site decay; and 3) free ligand concentration relative tokoff/k0n(n · Kd, where n is the fold increase in binding partner concentration needed to achieve a given fractional occupancy). Failure to satisfy these conditions results in fractional occupancy well below that corresponding to n · Kd. The implications of biodynamics for cellular function/dysfunction and drug discovery are discussed.
Logistic services in the Caribbean region
Authors: Ruiz-Torres Alex J. , Cardoza Guillermo , Kuula Markku , Oliver Yuritza , Rosa-Polanco Henry
Published: August 2018

Purpose

The purpose of this paper is to study the relationships between the capabilities and performance characteristics of logistic service providers (LSPs) in the Caribbean region. The study considers the organization’s process improvement (PI) performance as it relates to their innovation capabilities, their efforts into information sharing and collaboration with customers, their planning for contingencies and considering the uncertainty of their customer’s technology.

Design/methodology/approach

A survey was applied to 88 LSP firms with operations in the Caribbean region. Structural equation modeling was used to analyze the hypothesized relationships.

Findings

The results indicate that the PI performance of LSPs is significantly related to their innovation capabilities, and that these capabilities are positively related to collaboration and exchange of relevant information. Furthermore, they indicate that information sharing between LSPs and their customers significantly improves the quality of contingency planning. However, the study showed that innovation capabilities are not directly related to the LSPs’ focus on contingency planning and that customers’ technology uncertainty does not have a significant effect on the LSPs’ innovation capabilities.

Research limitations/implications

The sample of LSP firms is limited to three countries of the Caribbean region. Further examination of the model in additional countries and across multiple industrial contexts would increase the validity of the findings and expand to settings such as manufacturing and services.

Originality/value

This study measures operational performance of LSPs from a different perspective: its PI performance, and considers how multiple factors affect this performance.
Job satisfaction among senior managers and employees
Authors: Lasierra Jose Manuel
Published: August 2018

Purpose

Using selected personal and job-related variables, the purpose of this paper is to analyse job satisfaction among public sector senior managers and employees and then compare both cohorts with private-sector managers and employees.

Design/methodology/approach

The authors apply a General Linear Univariate Model with interactions that allows us to detect the influence of the independent variables based on the baseline reference value.

Findings

Results indicate that public employees differ considerably from employees in the private sector, while public sector managers’ behaviour and preferences are very similar to those of private-sector managers.

Research limitations/implications

One main conclusion is that the management function of senior managers is basically the same, whether they are in the public or private sectors, and, thus, private management techniques, such as new public management (NPM), can be applied to the public sector. The main shortcoming of the study is that a qualitative analysis does not allow us to observe the impact of ethical aspects that could guide value-oriented management.

Practical implications

Difficulties in management by public-sector managers may arise from public employees’ perceptions regarding the application of private management practices.

Social implications

High job-satisfaction ratings by public managers may indicate that, in spite of their lower wages compared to the private sector, there is no reason to conclude that a suboptimal staffing of public managers might occur that would jeopardise public services.

Originality/value

The authors are unaware of precedents that analyse differences between the public and private sectors in comparing employees and senior managers. Uniquely, the authors use a very large sample to draw conclusions. This paper can guide public senior managers who work in public administration.
Diversity management in three Latin American countries: an institutional theory perspective
Authors: Raineri Andrés
Published: August 2018

Purpose

The purpose of this paper is to use an institutional theory (IT) approach to analyse the institutional context for diversity management (DM) in Chile, El Salvador and Guatemala, the influence of such a context on the DM issues that organisations’ face, and the DM practices that firms implement.

Design/methodology/approach

Focus groups and a survey are used to assess managers and workers’ perceptions about DM in their countries, while an analysis of the content of firms’ web pages is used to assess the formal public information about DM provided by firms.

Findings

Results suggest prevalence of perceptions, among both managers and employees, of discrimination at the workplace, facilitated by cultural forces that undervalue human diversity. Firms’ DM responses seem to be led by multinational companies, and focussed on fighting discrimination, facilitating inclusion and pursuing external legitimacy.

Originality/value

This study is among the first to analyse DM in Latin American organisations. Furthermore, three studies, with different methodologies, support several IT propositions that emphasise the role of institutional forces in explaining organisations’ implementation of DM practices. The relevance and challenges of developing DM programmes in Latin America are discussed.
Immigrant entrepreneurs in Antofagasta, Chile
Authors: Rodrigo Luis Miguel , Romaní Gianni , Ricci Emilio
Published: August 2018

Purpose

The purpose of this paper is to characterize the immigrant entrepreneurs of the Region of Antofagasta and identify their contribution to local development.

Design/methodology/approach

This is a descriptive study with a quantitative approach. Face-to-face interviews using a structured questionnaire were carried out with a sample of 314 immigrant entrepreneurs in the city of Antofagasta. The data were analysed using descriptive statistics and mean difference.

Findings

The results show a new type of entrepreneur that cannot be fully described by the theories developed for South–North immigrant entrepreneurs. The concept of the South–South entrepreneur is therefore proposed, in order to categorise these entrepreneurs and explain their behaviour, with the conclusion that this group makes a significant contribution to the local economy, both in terms of job and wealth creation and by broadening the availability of goods and services.

Practical implications

Given that immigrant entrepreneurs are a valuable socio-economic asset to the city in terms of job and wealth creation and service diversification, public administrations should endeavour to support these individuals and attract them to the city.

Social implications

Knowledge of the contribution of this group will lead to a greater acceptance of immigrants who have recently been rejected by certain sectors of the population.

Originality/value

This study reveals the existence of a group of immigrant entrepreneurs whose characteristics and contribution to local development were previously not known.
Modelling the cancellation behaviour of hotel guests
Authors: Falk Martin , Vieru Markku
Published: August 2018

Purpose

The purpose of this study is to provide new insights into the factors that influence cancellation behaviour with respect to hotel bookings. The data are based on individual bookings drawn from a hotel reservation system database comprising nine hotels.

Design/methodology/approach

The determinants of cancellation probability are estimated using a probit model with cluster adjusted standard errors at the hotel level. Separate estimates are provided for rooms booked offline, through online travel agencies and through traditional travel agencies.

Findings

Evidence based on 233,000 bookings shows that the overall cancellation rate is 8 per cent. Cancellation rates are highest for online bookings (17 per cent), followed by offline bookings (12 per cent) and travel agency bookings (4 per cent). Probit estimations show that the probability of cancelling a booking is significantly higher for early bookings, large groups that book offline, offline bookings during high seasons, bookings not involving children and bookings made by guests from specific countries (e.g. China and Russia). Among the factors, booking lead time and country of residence play the largest role, particularly for online bookings.

Research limitations/implications

The analysis is based on individual-level booking data from one hotel chain in Finland, and therefore cannot be generalised for the total population of hotels in the country under observation.

Originality/value

The main contribution of this paper is a thorough investigation of the factors that influence cancellation behaviour at both the theoretical and empirical levels. Detailed and unique data from a hotel reservation system allow for new empirical insights into this behaviour.
Marketing for the project: project marketing by the contractor
Authors: Turner John Rodney , Lecoeuvre Laurence , Sankaran Shankar , Er Michael
Published: August 2018

Purpose

The purpose of this paper is to identify the marketing practices adopted by contractors in project-based industries to win new business and maintain relationships with existing clients.

Design/methodology/approach

The authors interviewed eight such contractors, and used activity theory as a lens to analyze the results. The authors investigated project marketing activities at four stages of the project contract life cycle, and against four enablers of collaboration.

Findings

The authors have identified that the service-dominant logic pervades project marketing. Through the project contract life cycle the marketing activity starts with a strategic focus, becomes tactical, then operational and returns to strategic. Project marketing involves executive managers, marketing, client or account managers and project managers. Project managers have a key responsibility for project marketing. The four enablers of collaboration, relationships, communication, going-with and trust, support each other and the entire project marketing activity.

Research limitations/implications

As a contribution to theory, the authors have identified the practices adopted by contractors in project-based industries to market their competencies to clients to win new work and maintain relationships with existing clients. The authors have identified practices throughout the contract life cycle, and practices to develop collaboration. The next step will be to explain these practices in terms of traditional marketing theory.

Practical implications

The results provide guidelines to contractors in project-based industries who wish to improve their marketing activity to achieve sustainable performance. Industry may also find it useful to train or coach their project managers to be conscious of their marketing role.

Originality/value

Previous work has been conceptual in nature and has speculated on the nature of the project marketing performed by contractors to win new projects, and set it against marketing done by the project. This research has empirically investigated the actual marketing practices adopted by project contracting organizations, shown how it varies through the project life cycle and shown how responsibility passes from senior management to the account team and then to project managers. It has also investigated the application of the four enablers of collaboration: relationships, communication, going-with and trust.
Experimental research on frictional resistance of smart isolation tool during maintenance operation in offshore pipeline
Authors: Zhang Kang , Zhu Xiaoxiao , Zhang Shimin , Ding Qingxin , He Zichen
Published: August 2018

Purpose

Pipeline maintenance technology using smart isolation tool is becoming more widely used in the global scope. This paper aims to investigate the effects of parameters on the frictional resistance between the slip and pipeline and the frictional characteristics under different lubrication films.

Design/methodology/approach

An experimental platform consisting of slip, pipeline and data acquisition system was developed, wherein the slip slips on the pipeline under different normal forces and velocities. In addition, three lubrication conditions, namely, dry wall, oil liquid and black powder on the wall, were investigated to study the effects of lubrications on the frictional coefficient and characteristics.

Findings

Research results indicate that the frictional force and coefficient were sensitive to normal force. The crude oil affected the frictional coefficient within a certain range of normal force, and the black powder enhanced the surface roughness in the natural gas pipeline. However, velocity had no effect on them. In addition, different contact behaviors could be observed from the frictional coefficient curves.

Originality/value

In this paper, the effects of normal force and velocity on frictional resistance of sliding slip during decelerating process in pipeline were investigated, and the effects of lubrication films on frictional characteristics were also revealed. The research results are of great value to improve the prediction accuracy of smart isolation tool, and also provide a guiding significance for the development of maintenance operation in pipelines.
An outcome-based process optimization model using fuzzy-based association rules
Authors: Lau Henry , Lee C.K.M. , Nakandala Dilupa , Shum Paul
Published: August 2018

Purpose

The purpose of this paper is to propose an outcome-based process optimization model which can be deployed in companies to enhance their business operations, strengthening their competitiveness in the current industrial environment. To validate the approach, a case example has been included to assess the practicality and validity of this approach to be applied in actual environment.

Design/methodology/approach

This model embraces two approaches including: fuzzy logic for mimicking the human thinking and decision making mechanism; and data mining association rules approach for optimizing the analyzed knowledge for future decision-making as well as providing a mechanism to apply the obtained knowledge to support the improvement of different types of processes.

Findings

The new methodology of the proposed algorithm has been evaluated in a case study and the algorithm shows its potential to determine the primary factors that have a great effect upon the final result of the entire operation comprising a number of processes. In this case example, relevant process parameters have been identified as the important factors causing significant impact on the result of final outcome.

Research limitations/implications

The proposed methodology requires the dependence on human knowledge and personal experience to determine the various fuzzy regions of the processes. This can be fairly subjective and even biased. As such, it is advisable that the development of artificial intelligence techniques to support automatic machine learning to derive the fuzzy sets should be promoted to provide more reliable results.

Originality/value

Recent study on the relevant topics indicates that an intelligent process optimization approach, which is able to interact seamlessly with the knowledge-based system and extract useful information for process improvement, is still seen as an area that requires more study and investigation. In this research, the process optimization system with an effective process mining algorithm embedded for supporting knowledge discovery is proposed for use to achieve better quality control.
Sponsorship image transfer theory in virtual brand communities
Authors: Alonso Dos Santos Manuel , Rejón Guardia Francisco , Calabuig Moreno Ferran
Published: August 2018

Purpose

The purpose of this paper is to assess the influences and efficiency of a sports sponsorship in an online brand community.

Design/methodology/approach

The study was conducted through interviews with 609 social network users of a Spanish first league soccer team. The partial least squares (PLS) methodology was applied with a posteriori segmentation (PLS prediction-oriented segmentation (POS)).

Findings

The attitude toward the sponsor helps to assess the efficiency of sponsorships between companies. This variable is particularly relevant for evaluating sponsorship efficiency in online brand communities. Improving trust and assessing the sense of membership directly improves attitudes toward the team and the sponsored brands. The attitude toward the sponsor has a direct and positive impact on the purchase intentions. The use of a posteriori segmentation with the PLS–POS technique helps discriminate between groups.

Research limitations/implications

Among the limitations encountered, further study would require using a sample of various sports disciplines and cultures.

Practical implications

Specific actions and communication strategies are defined for each segment and in general to adapt communication strategies that improve identification with virtual brand communities. The study has revealed involvement-related differences resulting from the impact that engagement with the sponsored team may have on the assessed relationships.

Originality/value

The study of the effects of sponsorship and the use of a posteriori variables user segmentation in an online brand community are used.
Minimizing the risk of seaport operations efficiency reduction affected by vessel arrival delay
Authors: Wang Zhengxu , Guo Chonghui
Published: August 2018

Purpose

In seaport industries, vessel arrival delay is inevitable because of numerous factors, e.g. weather, delay due to the previous stop, etc. The period of delay can be as short at 15 min of as long as a few days. This causes disruption to the planned sea operation operations, and more importantly, to the resources utilization. In traditional berth allocation and quay crane assignment problems (BA-QCA), the risk of vessel arrival delay has not been considered. Accordingly, the purpose of this paper is to employ a proactive planning approach by taking into consideration the vessel arrival delay into the optimization of BA-QCA problems.

Design/methodology/approach

In the existing BA-QCA problems, vessel arrival time is usually deterministic. In order to capture the uncertainties of arrival delay, this paper models the arrival time as a probability distribution function. Moreover, this paper proposes to model the delay risk by using the period between the expected arrival time and the expected waiting time of a vessel. Lastly, the authors propose a new modified genetic algorithm and a new quay crane assignment heuristic to maximize the schedule reliability of BA-QCA.

Findings

A number of numerical experiments are conducted. First of all, the optimization quality of the proposed algorithm is compared with the traditional genetic algorithm for verifying the correctness of the optimization approach. Then, the impact of vessel arrival delay is tested in different scenarios. The results demonstrate that the impact of vessel arrival delay can be minimized, especially in the situations of high vessel to potential berth ratio.

Research limitations/implications

The proposed vessel arrival modeling approach and the BA and QCA approach can increase the operations efficiency of seaports. These approaches can increase the resource utilization by reducing the effect of vessel arrival delay. In other words, this can improve the throughput of seaport terminals.

Originality/value

This paper proposes to minimize the delay risk based on the conditional probability of the vessel completion time based on the previous vessel at the assigned berth. This modeling approach is new in literature.
Creativity, bravery and the need for agencies to adapt to the challenge of technology
Authors: Abdulkarim Jehan
Published: August 2018

Purpose

The purpose of this paper is to address the relationship between organizations and their communication agencies. The paper argues that the relationship is symbiotic; both parties have to understand the importance of adapting their engagement with one another, especially if they hope to produce brand work that is impactful for target audiences and highlights the value of good communications and marketing to leadership.

Design/methodology/approach

The views expressed in this practice paper are based on the author’s extensive experience in the communications sector in the Middle East.

Findings

The paper highlights the importance of human creativity in communication campaigns, the need for bravery in marketing communications, and the need to adapt to technology. The best client/agency relationships combine the right degree of closeness and distance that allows agencies to be passionate advocates for the client while also being honest on stakeholder reactions. But, honesty requires courage. Telling a client what they need to hear and putting aside the fear of upsetting those who pay the bills in the search for the most effective creative idea takes nerve. Finally, the greatest change to the practice of communication is technology.

Originality/value

Although the relationship between clients and their communications agencies has been a topic of interest, much of the focus has been on the bottom line. This has been attributed to multiple reasons such as increased digital focus, or a belief among many brands that developing in-house capabilities provides better returns on investment. This practice paper addresses the agency–client relationship from a different perspective arguing for a symbiotic relationship built on creativity, honesty, bravery and the need to adapt to technology.
Opportunities and challenges of foreign direct investment utilisation and its impact on construction sector in developing countries
Authors: Babatunde Solomon Olusola , Awodele Oluwaseyi Alabi , Adeniyi Onaopepo
Published: August 2018

Purpose

Foreign direct investment (FDI) inflows to both developed and developing countries have increased over the past three decades. However, investigation of opportunities and challenges associated with FDI on the host economy and its impact, especially on the construction sector through empirical assessment, have received scant attention. The purpose of this study is to address this gap in knowledge within the Nigerian context and examine the trend of FDI inflows to the construction sector for the period 2000-2013 inclusive. Relationships between contributions of the construction sector to Nigeria’s gross domestic product (GDP) are also studied.

Design/methodology/approach

The study adopted a literature review, a questionnaire survey and archival data culminated in data analysis. The survey targeted financial experts in Nigerian financial institutions/local banks. Archival data included the annualised data extracted from the Central Bank of Nigeria statistical bulletins. The period examined witnessed stable economic conditions. Data collected were analysed using mean score, factor analysis and correlation.

Findings

Eight identified opportunities of using FDI were grouped into three principal factors: knowledge spillovers, capital for new investment and resilience during financial crises. The ten identified FDI challenges were grouped into three major factors: loss of ownership advantage and additional costs, crowding-out of-national firms and administrative bottleneck and overdependence. Based on the hypotheses tested, the study found a significant relationship between the contributions of FDI inflows in the construction sector and the total GDP of the host country.

Practical implications

This study provides greater insight on the effects of FDI on a host economy in developing countries, which would help policymakers to examine existing policies and look for new ways of increasing foreign investment flow, especially in the area of Construction Facility Investment.

Originality/value

This study is important because it would enable policymakers in developing countries at large to promote FDI with special considerations for the construction sector of the economy.
Managerial learning challenges in a complex world
Authors: Abreu Pederzini Gerardo David
Published: August 2018

Purpose

Managers’ work is surrounded by complex environments, from which they need to learn, in order to understand them. However, complexity poses several challenges to managerial learning, for which usually management educational programs have not prepared managers. Thus, the purpose of this paper is to explore such challenges and possible ways to overcome them.

Design/methodology/approach

This is a conceptual paper that explores in depth the issue of managerial learning challenges in a complex world. Managers face these challenges during their practice, yet sometimes management education has not prepared them for this.

Findings

Three managerial learning challenges due to complexity are identified. First, through cognition and cognitive structures, managers simplify the world around them. Nevertheless, biases, inertia and inaccuracy emerge, as managers’ mental models are not truly capable of capturing complexity. Second, managers look for information to aid them in their learning processes, but the information they gather is sometimes bogus, invalid or unfounded. Third, managers could seek for support from management research to improve their learning. However, given management research intricacies, limitations and particularities, a learning challenge emerges as well, as management research has been rarely capable to capture complexity.

Originality/value

Having explored these managerial learning challenges due to complexity, this paper discusses a carefulness-based management learning ideal, which by being underpinned by the quality of carefulness and the related concepts of critical thinking, negative capability and a deep learning style, suggests a potential new way to approach management learning in light of complexity.
Orthographic learning in Spanish children: influence of previous semantic and phonological knowledge
Authors: Álvarez‐Cañizo Marta , Suárez‐Coalla Paz , Cuetos Fernando
Published: August 2018

Orthographic learning is one of the steps needed to achieve reading fluency. There are different variables that could influence the formation of orthographic representations. The aim of this study was to investigate the role of the previous semantic and phonological knowledge on the formation of orthographic representations. We used a decrease of the length effect as the measure of orthographic learning. We made a reading aloud task that utilised new words with Spanish children from third grade under three different conditions: with prior semantic and phonological training, with prior phonological training and without training. Results showed that knowing the meaning and the phonological form of the words facilitated the formation of orthographic representations, as the length effect was significantly lower than in the other conditions, and it also improved the children's reading performance.
Exploring social media use in university crisis communication: An experiment to measure impact on perceived crisis severity and attitudes of key publics
Authors: Hong Seoyeon , Kim Bokyung
Published: August 2018

This study seeks to investigate the impact of an exposure to a university's social media on publics’ perceptions during a crisis. Data from this study showed that participants (N = 269) expressed more favourable evaluations towards the university and their perceived severity was mitigated after viewing its official statement on university's Facebook posts. The results of this empirical research offer a meaningful suggestion to crisis communication scholars and practitioners interested in assessing the impact of universities’ statements in social media by providing ways to understand the importance of the organizational usage of social media during a crisis, why that is important, and why practitioners should make effective social media communication tactics a priority during a crisis.