bluuebunny/crossref_metadata_2025 huggingface dataset:
Deciphering the rules underlying xenogeneic silencing and counter-silencing of Lsr2-like proteins
Authors: Wiechert Johanna , Filipchyk Andrei , Hünnefeld Max , Gätgens Cornelia , Heermann Ralf , Frunzke Julia
Published: August 2019

Lsr2-like nucleoid-associated proteins play an important role as xenogeneic silencers (XS) of horizontally acquired genomic regions in actinobacteria. In this study, we systematically analyzed the in vivo constraints underlying silencing and counter-silencing of the Lsr2-like protein CgpS inCorynebacterium glutamicum. Genome-wide analysis revealed binding of CgpS to regions featuring a distinct drop in GC-profile close to the transcription start site (TSS), but also identified an overrepresented motif with multiple A/T steps at the nucleation site of the nucleoprotein complex. Binding of specific transcription factors (TFs) may oppose XS activity leading to counter-silencing. Following a synthetic counter-silencing approach, target gene activation was realized by inserting operator sites of an effector-responsive TF within various CgpS target promoters resulting in an increased promoter activity upon TF binding. Analysis of reporter constructs revealed maximal counter-silencing when the TF operator site was inserted at the position of maximal CgpS coverage. This principle was implemented in a synthetic toggle switch, which features a robust and reversible response to effector availability highlighting the potential for biotechnological applications. Altogether, our results provide comprehensive insights into how Lsr2 silencing and counter-silencing shapes evolutionary network expansion in this medically- and biotechnologically-relevant bacterial phylum.

IMPORTANCE

In actinobacteria, Lsr2-like nucleoid-associated proteins function as xenogeneic silencers (XS) of horizontally acquired genomic regions, including viral elements, virulence gene clusters inMycobacterium tuberculosis, and genes involved in cryptic specialized metabolism inStreptomycesspecies. Consequently, a detailed mechanistic understanding of Lsr2 binding in vivo is relevant as a potential drug target and for the identification novel bioactive compounds. Here, we followed an in vivo approach to investigate the rules underlying xenogeneic silencing and counter-silencing of the Lsr2-like XS CgpS fromCorynebacterium glutamicum. Our results demonstrated that CgpS distinguishes between self and foreign by recognizing a distinct drop in GC-profile in combination with a short, sequence specific motif at the nucleation site. Following a synthetic counter-silencer approach, we studied the potential and constraints of transcription factors to counteract CgpS silencing thereby facilitating the integration of new genetic traits into host regulatory networks.
AMPK regulates ESCRT-dependent microautophagy of proteasomes concomitant with proteasome storage granule assembly during glucose starvation
Authors: Li Jianhui , Breker Michal , Graham Morven , Schuldiner Maya , Hochstrasser Mark
Published: August 2019

The ubiquitin-proteasome system regulates numerous cellular processes and is central to protein homeostasis. In proliferating yeast and many mammalian cells, proteasomes are highly enriched in the nucleus. In carbon-starved yeast, proteasomes migrate to the cytoplasm and collect in phase-separated proteasome storage granules (PSGs). PSGs dissolve and proteasomes return to the nucleus within minutes of glucose refeeding. The mechanisms by which cells regulate proteasome homeostasis under these conditions remain largely unknown. Here we show that AMP-activated protein kinase (AMPK) together with endosomal sorting complexes required for transport (ESCRTs) drive a glucose starvation-dependent microautophagy pathway that preferentially sorts aberrant proteasomes into the vacuole, thereby biasing accumulation of functional proteasomes in PSGs. The proteasome core particle (CP) and regulatory particle (RP) are regulated differently. Without AMPK, the insoluble protein deposit (IPOD) serves as an alternative site that specifically sequesters CP aggregates. Our findings reveal a novel AMPK-controlled ESCRT-mediated microautophagy mechanism in the regulation of proteasome trafficking and homeostasis under carbon starvation.
The burden of cutaneous and mucocutaneous leishmaniasis in Ecuador (2014-2018), a national registry-based study
Authors: Henríquez-Trujillo Aquiles R. , Coral-Almeida Marco , Calvopiña Hinojosa Manuel
Published: August 2019

Background

Cutaneous (CL) and mucocutaneous (MCL) leishmaniasis remain as endemic tropical diseases in several Latin American countries. This study aimed to estimate the burden of CL and MCL in Ecuador for the period 2014-2018, in order to inform decision-making and resource allocation to tackle this neglected disease.

Methods

Ambulatory consultations, hospitalizations, and reported cases of Leishmaniasis registered by the Ecuadorian National Institute of Statistics and Census and the Ministry of Public Health were used to estimate the burden of CL and MCL during a five-year period. Case estimations were stratified by prevalence of acute and long-term sequelae, to calculate Years Lived with Disability (YLD) by sex and age group using the DALY package in R. Spatial analysis was conducted to identify statistically significant spatial clusters of leishmaniasis.

Results

Between years 2014 and 2018, a total 6,937 cases of leishmaniasis were registered, with an average of 1,395 cases reported per year, 97.5% of them were CL and 2.5% MCL. The average cumulative incidence for the study period corrected for underreporting was estimated in 21.98 to 36.10 per 100 thousand inhabitants. Health losses due to leishmaniasis reach 0.32 DALY per 100,000 people per year (95% CI 0.15 – 0.49). The most affected by the disease were men between 15 to 64 years old living below 1,500 m.a.s.l. in sub-tropical and tropical rural communities on both slopes of the Andes mountains. Cantons with the highest cumulative incidence of CL and MCL were Pedro Vicente Maldonado, San Miguel de Los Bancos, and Puerto Quito, in the Pichincha Province; Taisha and Aguarico in the Morona Santiago and Orellana provinces respectively.

Conclusion

Compared to previous reports, in the past five years CL and MCL persist as a public health problem in Ecuador. There is a need for more comprehensive and robust data sources to track leishmania cases in Ecuador.

Author summary

Cutaneous (CL) and mucocutaneous (MCL) leishmaniasis remains as an endemic neglected tropical disease in several Latin American countries, including Ecuador. Both CL and MCL can produce disfiguring lesions on exposed parts of the body like face and extremities, and permanent scars, contributing to the burden of the disease due to stigma. In order to inform health authorities in their efforts to improve the control of the transmission of the Leishmaniases in the Ecuadorian population, we estimate the burden of CL and MCL for Ecuador in the period 2014-2018, calculating the years lived with disability due to acute and chronic sequelae. We also look for geographical regions within Ecuador with significant clusters of people with the disease, and we found 17 spatial clusters in sub-tropical and tropical rural communities below 1,500 m.a.s.l. on both slopes of the Andes mountains.
Prognostics for pain in osteoarthritis: Can clinical measures predict pain after total joint replacement?
Authors: Barroso Joana , Wakaizumi Kenta , Reckziegel Diane , Pinto-Ramos João , Schnitzer Thomas , Galhardo Vasco , Apkarian A. Vania
Published: August 2019

A significant proportion of osteoarthritis (OA) patients continues to experience moderate to severe pain after total joint replacement (TJR). So far, preoperative factors related to pain persistence have been mainly studied using individual predictor variables and distinct pain outcomes, thus leading to lack of consensus in the field. In this prospective observational study, we evaluated knee and hip OA patients before, 3 and 6 months post-TJR searching for clinical predictors of pain persistence. We assessed multiple measures of quality, mood, affect, health and quality of life, together with radiographic evaluation and performance-based tasks, modeling four distinct pain outcomes. Multivariate regression models were built, and a network analysis was applied to pain related biopsychosocial measures and their change with surgery. A total of 106 patients completed the study. Pre-surgical pain levels were not related to post-surgical residual pain. Distinct pain scales were associated with different aspects of the pain experience. Multi-factorial models did not reliably predict post-surgical pain in knee OA across four distinct pain scales and did not generalize to hip OA; however, network analysis of pain related biopsychosocial measures showed significant changes post-surgery in both groups. Our results show that although tested clinical and biopsychosocial variables are reorganizing after TJR in OA, they do not present as a robust markers for post-surgery pain outcomes. A better understanding of mechanisms underlying pain persistence after TJR is necessary to derive clinical prognostic factors.
Olfactory Landmarks and Path Integration Converge to Form a Cognitive Spatial Map
Authors: Fischler Walter M. , Joshi Narendra R. , Devi-Chou Virginia , Kitch Lacey J. , Schnitzer Mark J. , Abbott Larry F. , Axel Richard
Published: August 2019

The convergence of internal path integration with sensory information from external landmarks generates a cognitive spatial map in the hippocampus. We have recorded the activity of cells in CA1 during a virtual navigation task to examine how mice represent, recognize and employ sparse olfactory landmarks to estimate their location. We observe that the presence of odor landmarks at multiple locations in a virtual environment greatly enriches the place cell representation and dramatically improves navigation. Presentation of the same odor at different locations generates distinct place cell representations, indicating that path integration can disambiguate two identical cues on the basis of location. The enhanced place cell representation at one cue location led to the formation of place cells at locations beyond that cue and, ultimately recognition of a second odor cue as a distinct landmark. This suggests an iterative mechanism for extending place cell representations into unknown territory. These results reveal how odor cues can serve as landmarks to guide navigation and suggest a model to explain how the convergence of landmarks and path integration participates in an iterative process that generates a cognitive spatial map.
Fast and robust detection of colistin resistance in Escherichia coli using the MALDI Biotyper Sirius mass spectrometry system
Authors: Furniss R. Christopher D. , Dortet Laurent , Bolland William , Drews Oliver , Sparbier Katrin , Bonnin Rémy A. , Filloux Alain , Kostrzewa Markus , Mavridou Despoina A.I. , Larrouy-Maumus Gerald
Published: August 2019

Polymyxin antibiotics are a last-line treatment for multidrug-resistant Gram-negative bacteria. However, the emergence of colistin resistance, including the spread of mobile mcr genes, necessitates the development of improved diagnostics for the detection of colistin-resistant organisms in hospital settings. The recently developed MALDIxin test enables detection of colistin resistance by MALDI-TOF mass spectrometry in less than 15 minutes but is not optimized for the mass spectrometers commonly found in clinical microbiology laboratories. In this study, we adapted the MALDIxin test for the MALDI Biotyper Sirius MALDI-TOF mass spectrometry system (Bruker Daltonics). We optimized the sample preparation protocol using a set of 6 MCR-expressing Escherichia coli clones and validated the assay with a collection of 40 E. coli clinical isolates, including 19 MCR producers, 12 chromosomally-resistant isolates and 9 polymyxin-susceptible isolates. We calculated Polymyxin resistance ratio (PRR) values from the acquired spectra; a PRR value of zero, indicating polymyxin susceptibility, was obtained for all colistin-susceptible E. coli isolates, whereas positive PRR values, indicating resistance to polymyxins, were obtained for all resistant strains independent of the genetic basis of resistance. Thus, we report a preliminary feasibility study showing that an optimized version of the MALDIxin test, adapted for the routine MALDI Biotyper Sirius, provides an unbiased, fast, reliable, cost-effective and high-throughput way of detecting colistin resistance in clinical E. coli isolates.
Structural Studies of Overlapping Dinucleosomes in Solution
Authors: Matsumoto A. , Sugiyama M. , Li Z. , Martel A. , Porcar L. , Inoue R. , Kato D. , Osakabe A. , Kurumizaka H. , Kono H.
Published: August 2019

An overlapping dinucleosome (OLDN) is a structure composed of one hexasome and one octasome and appears to be formed through nucleosome collision promoted by nucleosome remodeling factor(s). In the present study, the solution structure of the OLDN was investigated through integration of small-angle X-ray and neutron scattering (SAXS and SANS, respectively), computer modeling, and molecular dynamics simulations. Starting from the crystal structure, we generated a conformational ensemble based on normal mode analysis, and searched for the conformations that well reproduced the SAXS and SANS scattering curves. We found that inclusion of histone tails, which are not observed in the crystal structure, greatly improved model quality. The obtained structural models suggest that OLDNs adopt a variety of conformations stabilized by histone tails situated at the interface between the hexasome and octasome, simultaneously binding to both the hexasomal and octasomal DNA. In addition, our models define a possible direction for the conformational changes or dynamics, which may provide important information that furthers our understanding of the role of chromatin dynamics in gene regulation.

Statement of Significance

Overlapping dinucleosomes (OLDNs) are intermediate structures formed through nucleosome collision promoted by nucleosome remodeling factor(s). To study the solution structure of OLDNs, a structural library containing a wide variety of conformations was prepared though simulations, and the structures that well reproduced the small angle X-ray and neutron scattering data were selected from the library. Simultaneous evaluation of the conformational variation in the global OLDN structures and in the histone tails is difficult using conventional MD simulations. We overcame this problem by combining multiple simulation techniques, and showed the importance of the histone tails for stabilizing the structures of OLDNs in solution.
A new small-angle X-ray scattering model for polymer spherulites with a limited lateral size of the lamellar crystals
Authors: Li Xiang-Yang , Ding Jian-Jun , Liu Yan-Ping , Tian Xing-You
Published: August 2019

As is well known, polymers commonly form lamellar crystals, and these assemble further into lamellar stacks and spherulites during quiescent crystallization. Fifty years ago, Vonk and Kortleve constructed the classical small-angle X-ray scattering theory (SAXS) for a lamellar system, in which it was assumed that the lamellar stack had an infinite lateral size [Vonk & Kortleve (1967), Kolloid Z. Z. Polym.
220, 19–24]. Under this assumption, only crystal planes satisfying the Bragg condition can form strong scattering, and the scattering from the lamellar stack arises from the difference between the scattering intensities in the amorphous and crystalline layers, induced by the incident X-ray beam. This assumption is now deemed unreasonable. In a real polymer spherulite, the lamellar crystal commonly has dimensions of only a few hundred nanometres. At such a limited lateral size, lamellar stacks in a broad orientation have similar scattering, so interference between these lamellar stacks must be considered. Scattering from lamellar stacks parallel to the incident X-ray beam also needs to be considered when total reflection occurs. In this study, various scattering contributions from lamellar stacks in a spherulite are determined. It is found that, for a limited lateral size, the scattering induced by the incident X-ray beam is not the main origin of SAXS. It forms double peaks, which are not observed in real scattering because of destructive interference between the lamellar stacks. The scattering induced by the evanescent wave is the main origin. It can form a similar interference pattern to that observed in a real SAXS measurement: a Guinier region in the small-q range, a signal region in the intermediate-q range and a Porod region in the high-q range. It is estimated that, to avoid destructive interference, the lateral size needs to be greater than 11 µm, which cannot be satisfied in a real lamellar system. Therefore, SAXS in a real polymer system arises largely from the scattering induced by the evanescent wave. Evidence for the existence of the evanescent wave was identified in the scattering of isotactic polypropylene. This study corrects a long-term misunderstanding of SAXS in a polymer lamellar system.
The positioning and competitive strategies of higher education institutions in the United Arab Emirates
Authors: Wilkins Stephen
Published: August 2019

Purpose

The purpose of this paper is to discover how higher education institutions may segment the market in a competitive higher education hub and to assess the usefulness of strategic group analysis as an analytical technique for market and competitor analysis. As a case example of a competitive higher education market, this research investigates how higher education institutions in the United Arab Emirates (UAE) position themselves and compete with one another.

Design/methodology/approach

The research relied mainly on secondary data, which were obtained from the websites of institutions and regulatory bodies. Then, hierarchical cluster analysis was used to identify strategic groups and institutional competitive strategies in the UAE higher education market. A panel of experts helped interpret and explain the cluster results.

Findings

Eight distinct institutional clusters were identified, which include public- and privately-owned institutions, as well as elite and specialist institutions. Institution and programme accreditation were found to be particularly important in the UAE market. The institutions in each group appear to operate in a particular market segment, targeting students who have similar needs and wants, and who often share similar demographic features.

Practical implications

It is concluded that strategic group analysis may help institutions to evaluate potential markets, select target segments and develop competitive strategies. In the UAE market context, the results demonstrate how institutions may position themselves to create strong and distinctive identities. The results of the research may be of interest to higher education institutions that operate in competitive markets, and particularly those that want to evaluate foreign markets.

Originality/value

This is believed to be the first study to use a strategic group approach for analysing competitors in a higher education hub.
A study of the mobility of mainland students
Authors: Wong Ping Man , Cheung Alan , Yuen Wai Wa
Published: August 2019

Purpose

The purpose of this paper is to contribute to a better understanding of the international mobility of mainland students in special administrative regions of China and in places outside China.

Design/methodology/approach

There have been studies using the framework of push–pull and reverse push–pull factors to explore the movement of mainland students to North America, Australia, Singapore and Hong Kong. This study follows up by exploring such research directions in Macau, which is another special administrative region of China. Different from previous studies, the sample of this study came specifically from 130 students enrolling in teacher education undergraduate programs in Macau.

Findings

In this study, using data collected from questionnaires and interviews, the factors affecting mainland student teachers’ choice of Macau as a place for their undergraduate studies are examined. Other related issues such as the challenges these students face and their intentions after their graduation are also studied.

Originality/value

The data collected for this study were primary and original, drawing specifically from students enrolling teacher education programs. Following the various studies on the global movement of mainland students, this study aimed at understanding mainland students’ mobility pattern in one of China’s special administration regions, Macau. In this regard, cultural identity and cultural factors were considered on top of other factors.
Developing gender-specific evidence-based standards to improve the health and wellbeing of women in prison in England: a literature review and modified eDelphi survey
Authors: McCann Lucy J. , Peden Jo , Phipps Emily , Plugge Emma , O’Moore Eamonn J.
Published: August 2019

Purpose

There are significant health inequalities experienced by women in prison. They face distinct challenges and have particular and complex needs, specifically with regard to their physical and mental health. The purpose of this paper is to describe the approach taken to develop a set of health and wellbeing standards for the women’s prison estate in England, which can be applied elsewhere.

Design/methodology/approach

A structured literature review of standard healthcare databases and grey literature was used to inform development of suggested standards. A multidisciplinary expert panel provided consensus on the standards through an online survey and women with a history of contact with the criminal justice system were consulted through consensus groups.

Findings

A total of 549 papers were included in the final review. From this, 127 standards were identified for inclusion in the Delphi process. Consensus was achieved on all standards; this, combined with the analysis of qualitative feedback provided by both the survey and the consensus groups, resulted in the development of 6 overarching principles and 122 standards, across ten topic areas.

Originality/value

These standards are the most extensive that are known to exist for health and wellbeing of women in prison and the first to be developed in England. The process used ensures the standards have high validity, acceptability and feasibility and can be used to support those developing similar methodologies. There are few papers which document the development of standards to improve health and to the authors knowledge, only one other paper has been published detailing the development of health standards in prison settings specifically.
A study on the promotional mix of pre-service in the view of service design
Authors: Qian Chenxiang , Wu Chih-Fu , Zhang Zhenbo , Huang Hsin-Yu
Published: August 2019

Purpose

The purpose of this paper is to explore current marketing communication mixes (MCMs) in two industries, electronics home appliance stores (face-to-face interaction) and remote care (interface-mediated interaction), to propose marketing strategies from the perspective of service design and determine the relationships between service interaction patterns and MCMs in the pre-service phase.

Design/methodology/approach

Six industry experts in marketing were interviewed through semi-structured interviews, the topic of which focused on the details of five MCMs and their correlations were analyzed using a customer journey maps. Finally, the MCMs were further explored to verify differences in attractiveness to customers, respectively.

Findings

The result showed that the most attractive activity for the electronics home appliance stores customer is the promotion. And the four face-to-face service interaction patterns and MCMs exhibited a low correlation. In addition, the customers of remote care service argued that the personnel selling was the most attractive MCMs to them. For customers who utilize smart devices to communicate with advertisement exhibited the highest correlation coefficient.

Research limitations/implications

The limitation of this study is that the research only conducts interview research on two service industries.

Practical implications

This study was expected to develop improved marketing communication strategies to remedy the sales predicament induced by virtual channels and to increase people’s acceptance of remote care service.

Originality/value

The value of this paper is to analyze the correlation and difference of MCMs and service interaction patterns between electronics home appliance stores and remote care, and propose a structural model of MCMs for two different industries.
From power to punishment: consumer empowerment and online complaining behaviors
Authors: Li Zongchao
Published: August 2019

Purpose

The purpose of this paper is to examine how psychological empowerment affects individuals’ likelihood of publicly punishing a company with whom they had unsatisfactory experiences through online complaining behaviors.

Design/methodology/approach

A 3 (intrapersonal empowerment: high/low/control) by 3 (interactional empowerment: high/low/control) online experiment was designed using the priming technique. Following the priming tasks, participants were given a scenario in which a restaurant failed their expectations followed by dependent and control measures.

Findings

Results revealed a significant main effect of interactional empowerment: participants in the low interactional empowerment condition reported being less likely to engage in the revenge-motivated online public complaining behaviors than participants in the control condition. The study also found a significant interaction effect between interactional and intrapersonal empowerment.

Practical implications

The study findings yield practical application for crisis management and relationship management. Understanding the linkage between power and online complaining behaviors should help corporate communication professionals to better perform risk assessment, environmental scanning and crisis communication and management.

Originality/value

Limited empirical studies have investigated the linkage between empowerment and online complaining behaviors in the consumer context. The present study fills this gap by conceptualizing online public complaining as a revenge-motivated behavior. The study yields both theoretical and practical implications.
B2B marketing renaissance in business schools
Authors: Mora Cortez Roberto
Published: August 2019

Purpose

The purpose of this paper is to contribute to the elevation of the business-to-business (B2B) marketing field at the business school level.

Design/methodology/approach

The study follows a Delphi method. The authors conducted two rounds of discovery to answer: why do you think universities do not highly appreciate publications in Industrial Marketing Management, Journal of Business and Industrial Marketing or Journal of Business-to-Business Marketing? What would you suggest for improving the impact of such journals not only in the USA but around the world?

Findings

Through the analysis of the coding transcript, four categories were found to elevate the B2B marketing field at the business school level: B2B as uncommon ground, B2B researcher practices, marketing science underpinnings and B2B marketing journals management.

Originality/value

The value of current research is based on its explorative nature and application of grounded theory to provide a framework to analyze how to elevate the B2B marketing field at the business school level.
Antecedents of demand-side search in servitization of manufacturing firms: the critical role of service-oriented HRM practices and market capability
Authors: Dang Beilei , Zhang Wenhong , Chen Silei , Feng Taiwen , Zhao Yapu
Published: August 2019

Purpose

The purpose of this paper is to explore the antecedents of demand-side search in service strategy of manufacturing firms. In particular, this study examines whether service-oriented human resource management (HRM) practices promote demand-side search by enhancing firms’ market capability as well as how top management service commitment and service organizing moderates this relationship in manufacturing firms.

Design/methodology/approach

To test this research model, this study obtains survey data from two distinct informants of 279 manufacturing firms in China. Data were collected applying a standard questionnaire in a five-point Likert scale. The hypotheses are tested using hierarchical regression analysis and partial least squares.

Findings

Results show that service-oriented HRM practices can promote demand-side search by enhancing firms’ market capability. Furthermore, it is found that top management service commitment negatively moderates the relationship between service-orientated HRM practices and demand-side search, while service organizing positively moderates this relationship.

Research limitations/implications

Depending on cross-sectional subjective data for the core variables and the choice of Chinese manufacturing firms limit the capacity to generalize the findings.

Practical implications

This research suggests that service-oriented HRM practices are important drivers of demand-side search activities and to take advantage of service-oriented HRM practices, firms should commit to market capability development. In addition, it is better to match service-oriented HRM practices with other service-oriented organizational parameters such as top management service commitment and service organizing.

Originality/value

The study highlights the crucial role of service-oriented HRM practices in demand-side search, the mediating role of market capability and the moderating role of other service-oriented organizational parameters such as top management service commitment and service organizing. This study advances research on knowledge search, servitization and strategic HRM.
Effectiveness of monetary discounts: comparing quantity scarcity and time restriction
Authors: Jha Subhash , Dutta Sujay , Koksal Ahmet
Published: August 2019

Purpose

This study aims to examine whether adding a quantity scarcity message to a monetary discount helps to improve consumers’ offer-related perceptions and intentions, and how the effectiveness of that message compares with adding time restriction to the offer.

Design/methodology/approach

Two experiments, where participants evaluated retail ads and responded to relevant measures, were conducted in two country markets.

Findings

Adding either a quantity scarcity message or time restriction to a monetary discount increases the potency of a retail offer. Further, when an offer ad emphasizes product and price-related cues in a balanced manner, time restriction results in more favorable consumer perceptions than scarcity. However, this difference in the messages’ efficacy disappears when the offer strongly emphasizes price-related cues.

Research limitations/implications

The US market sample is more homogeneous than the Indian one. Discounts were presented in terms of advertised reference prices; further research with other discount formats is desirable.

Practical implications

Understanding the relative efficacy of quantity scarcity message and time restriction in discounted retail offers can give managers flexibility in the use of these tools.

Originality/value

This paper addresses scholars’ call for theory-grounded research that provides guidance to retailers on the use of sales promotional tools.
Effect of surface roughness on ultrasonic inspection of electron beam melting ti‐6AL‐4V
Authors: Hanks Evan , Palazotto Anthony , Liu David
Published: August 2019

Purpose

Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of electron beam melted (EBM) additively manufactured Ti-6Al-4V. Additive manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include aircraft battle damage repair (ABDR), small batch manufacturing to fill supply gaps and replacement for obsolete parts. This paper aims to assess the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM-manufactured Ti-6Al-4V. Additively manufactured EBM products have a high surface roughness in “as-manufactured” condition which is an artifact of the manufacturing process. The surface roughness is known to affect the results of ultrasonic inspections. Experimental data from this research demonstrate the ability of ultrasonic inspections to identify imbedded flaws as small as 0.51 mm at frequencies of 2.25, 5 and 10 MHz through a machined surface. Detection of flaws in higher surface roughness samples was increased at a frequency of 10 MHz opposed to both lower frequencies tested.

Design/methodology/approach

The approach is to incorporate ultrasonic waves to identify flaws in an additive manufactured specimen

Findings

A wave frequency of 10 MHz gave good results in finding flaws even with surface roughness present.

Originality/value

To the best of the authors’ knowledge, this was the first attempt that was able to identify small flaws using ultrasonic sound waves in which surface roughness was present.
Research on decision-making behavior of crowdsourcing task based on loss aversion and incentive level
Authors: Wang Liang , Xu Tingjia , Chen Jie
Published: August 2019

Purpose

The purpose of this paper is to study the decision-making behavior of the initiator and the participant under innovative and project-based tasks, respectively. It further explores the impact of the participant’s loss aversion and the initiator’s incentive level on the participant’s optimal effort level to reveal the implicit managerial mechanism.

Design/methodology/approach

This paper uses the Principal-agent Theory, Prospect Theory and Game Theory to study the decision-making behavior in crowdsourcing tasks. First, according to the return at the reference point, it establishes the utility function models of the participant and the initiator. Second, based on diverse loss aversion coefficient and incentive coefficient, it constructs the decision-making models of two types of task respectively. Third, it verifies the validity of models through simulation analysis.

Findings

For innovative task, the participant’s optimal effort level increases with the increment of loss aversion and incentive level, but decreases with the increase of his effort cost. For project-based task, the participant’s optimal effort level rises with the decrease of loss aversion; if the initiator does not take appropriate incentives, information asymmetry will lead to the task becoming a low-level innovation approach. Moreover, under innovative task, when the participant has loss aversion (or loss aversion reversal), his optimal effort level is higher (or lower) than that with no loss aversion, while the result under project-based task is just the opposite.

Originality/value

This paper characterizes two types of crowdsourcing task. Based on the prospect theory, it develops the decision-making models of the participant and the initiator under innovative and project-based tasks, thus exploring the impact of loss aversion and incentive level on their decision-making behavior. According to the findings in this paper, the initiator may effectively speculate the participant’s effort level and adopt reasonable monetary incentive measures to optimize the crowdsourcing return. In addition, this study can provide some reference for the design of incentive mechanism in crowdsourcing tasks and improve the relevant research of crowdsourcing.
Let-down stability and screen printability of inks prepared using non-printing ink grades of carbon black pigment
Authors: Ali Muhammad , Lin Long , Faisal Saira , Ali Syed Rizwan , Ali Syed Imran
Published: August 2019

Purpose

This paper aims to analyse the let-down stability of the binder-free dispersion of non-printing ink grades of carbon black and to assess the screen-printability of the finished inks formulated thereof from these pigment dispersions.

Design/methodology/approach

Binder-free pigment dispersions that were prepared and optimised following a ladder series of experiments (reported in a separate study by the authors) were let-down with three different binders such that inks containing various amounts of a binder were prepared followed by a rheological characterisation immediately after formulation and after four weeks of storage. The screen printability of the inks that displayed considerable stability was assessed, so was the ink film integrity.

Findings

The pigment dispersions that were considered in the present study were generally found to be stable after let-down with different binders. This was indicated by the fact that the finished inks possessed a shear thinning viscosity profiles, after formulation and after storage, in most of the cases. Furthermore, the screen printability of the inks was also found to be good in terms of registration quality of a selected design. The structure of the ink film deposits on uncoated and binder-coated textile fabrics was also highly integrated and free from discontinuities.

Originality/value

Carbon blacks with very low volatile matter content and/or high surface area are generally not considered suitable for use in the formulation of printing inks. This is because of their generally poor dispersability and inability to form dispersions that remain stable over extended periods. This work, which is a part of a larger study by the authors, concerns with the stability of inks formulated from binder-free dispersions of such non-printing ink grades of carbon black. The major advantage of using such pigments in inks is that the required functionality is achieved at considerably low pigment loadings.
An investigation on the synthesis of nickel aluminate
Authors: Frolova Liliya
Published: August 2019

Purpose

The purpose of this paper is to study the process of coprecipitation of polyhydroxocomplexes of nickel and aluminum from solutions of nickel (Ni) (II) sulfate and aluminum (Al) (III) sulfate with caustic soda and to study the conversion process to nickel aluminate and to check its properties.

Design/methodology/approach

For the thermodynamic analysis of the precipitation process, the software package MEDUSA was used. The dependences of the electrical conductivity, pH and residual concentrations as functions of the OH/Me ratio were obtained. Using X-ray phase analysis, spectroscopic analysis and derivatographic analysis, the properties of the products obtained were studied. The effects of OH/Me ratio and molar ratio cation of reagents on the physicochemical properties of the products were analyzed.

Findings

The paper deals with the results of theoretical and experimental research on the synthesis pigments of blue and green colors based on Ni-Al spinel. The influence of the molar ratio cation content on optical and color characterise of pigments were studied.

Originality/value

The original complex method of studying the processes of co-precipitation of cations in the form of hydroxides is proposed. pH precipitation of aluminum hydroxide and nickel are different. It is interesting to study their co-precipitation. The resulting single-phase product is a precursor of nickel aluminate over a wide range of cation ratios. The dependences of the electrical conductivity, pH and residual concentrations as functions of the OH/Me ratio were obtained.
Nanoscale mechanical properties of 3D printed gypsum-powder-based rocks by nanoindentation and numerical modeling
Authors: Kong Lingyun , Ostadhassan Mehdi , Lin Ran , Li Chunxiao
Published: August 2019

Purpose

Evaluating mechanical properties of simply made samples by 3D printing technology at nanoscale provides a clear path to better understand larger-scale responses of complex natural rocks. Therefore, to realize the similarity between synthetically manufactured materials and natural geomaterials, this study focused on nanoscale mechanical characterization of a 3D printed object with only two constituent components (gypsum powder and infiltrant).

Design/methodology/approach

The study method includes nanoindentation technique combined with numerical simulation via discrete element method (DEM).

Findings

Four typical load-displacement curves were identified from nanoindentation of total test points indicating a typical elastic-plastic behavior of the 3D printed gypsum rock sample. Mechanical parameters such as Young’s modulus and hardness were calculated by energy-based methods and a positive correlation was observed. The infiltrant was found to considerably be responsible for the majority of the sample nano-mechanical behavior rather than the gypsum particles, thus expected to control macroscale properties. This was decided from deconvolution and clustering of elastic modulus data. Particle flow modeling in DEM was used to simulate the nanoindentation process in a porous media yielding rock-alike mechanical behavior.

Originality/value

The results show a matching load-displacement response between experimental and simulation results, which verified the credibility of simulation modeling for mechanical behavior of 3D printed gypsum rock at nanoscale. Finally, differential effective medium theory was used to upscale the nanoindentation results to the macroscale mechanical properties, which provided an insight into the geomechanical modeling at multiscale.
The mediating role of corporate social responsibility on the relationship between governance and tax avoidance: UK common law versus French civil law
Authors: Salhi Bassem , Riguen Rakia , Kachouri Maali , Jarboui Anis
Published: August 2019

Purpose

The purpose of this paper is to investigate the direct and indirect links between corporate governance and tax avoidance using corporate social responsibility (CSR).

Design/methodology/approach

This study is based on a sample consisting of 300 UK and 200 French firms over the period 2005-2017. This study is motivated by structural equations and system models that specify both a direct link and an indirect link between corporate governance and tax avoidance.

Findings

The results show that CSR fully mediates the relationship between corporate governance and tax avoidance in UK firms. In addition, in French firms, CSR partially mediates the relation between corporate governance and tax avoidance.

Practical implications

The findings may be of interest to the academic researchers, practitioners and regulators who are interested in discovering corporate governance score, tax avoidance and CSR. Regulators must evaluate their actual corporate governance mechanisms and their country’s legal system before mandating additional governance mechanisms for firms in their country.

Social implications

This study proved empirically that firms with a higher level of social responsibility are better positioned to obtain more transparency through reducing tax avoidance.

Originality/value

This paper extends the existing literature by examining the mediation effect of CSR on the relationship between tax avoidance and corporate governance.
Pursuing sustainable development with knowledge management in public sector
Authors: Al Yami Mohsenah , Ajmal Mian M.
Published: August 2019

Purpose

Knowledge management (KM) is increasingly becoming critical to public sector organizations as it is to private sector organizations. This is because public sector organizations are increasingly held accountable for their actions and are forced to move away from traditional bureaucratic approaches to more managerial ones. For instance, public sector is facing pressure to improve its operational efficiency such as productivity, lead time and expenditure. Similarly, it is also facing pressure to improve its transparency, trust, reliability and accountability, which are key elements of sustainable development (SD). The purpose of this study therefore is to understand the intricate relationship between KM processes, operational efficiency and SD in the public sector.

Design/methodology/approach

A framework consisting of eight constructs (knowledge acquisition, knowledge creation, knowledge capture, knowledge storage and retrieval, knowledge sharing, knowledge utilization, operational efficiency and SD) and their underlying items was developed through an extensive literature review. Using 383 usable responses collected through a structured questionnaire from the UAE public sector, the constructs and framework were first validated and then the current level of implementation/achievement of KM processes, operational efficiency and SD was assessed along with the hypothesized relationships between the constructs.

Findings

The findings show that KM processes had a positive and significant direct impact on operational efficiency and SD. Also, operational efficiency was found to strongly mediate the relationship between KM processes and SD.

Practical implications

The findings are expected to help UAE public sector organizations devise strategies and policy interventions to align and improve their KM processes for achieving operational efficiency and SD. Public sectors looking to focus on SD must focus on KM processes and strive to improve stakeholder engagement, which is a vital aspect of SD.

Originality/value

Integration of KM processes, operational efficiency and SD has not been attempted previously and hence constitutes the novelty of this work.
Selection and prioritization of knowledge management strategies as proportionate with organizations” level of maturity using fuzzy TOPSIS approach, case study
Authors: Akhavan Peyman , Philsoophian Maryam , Karimi Mohamad Hosein
Published: August 2019

Purpose

Due to importance of knowledge management (KM) strategies in successful implementation of KM processes and saving time and expense, selection of suitable KM strategies has been changed to be a major concern by many organizations. Therefore, this is necessary for organizations to move along KM processes in selection and establishment of their strategies at their first step. An influential factor in selection of KM strategies is measurement and identification of an organization’s condition of its knowledge maturity. Accordingly, this paper aims to select and prioritize KM strategies as proportionate with an organization’s level of maturity.

Design/methodology/approach

For that, the author-constructed questionnaire was designated based on the opinions made by experts acquainted with KM and KM strategies. According to experts’ opinions, the paradigm for suggestion of strategies was elucidated based on KM’s level of maturity. Afterwards, the standard questionnaire knowledge navigator model was used to evaluate the organization’s level of maturity, and KM strategies for the organization were proposed based on identified level of maturity. Finally, proposed KM strategies were ranked using the fuzzy TOPSIS technique.

Findings

In this study, a paradigm for selection of suitable KM strategies was proposed based on Hansen KM strategy as per maturity level of the organization’s KM. Then, knowledge conditions of a research organization were evaluated, and, after maturity level of that organization’s KM was assessed, different criteria of Hansen KM strategy were suggested for each level independently. Research results are indicative of the fact that the intended organization is placed at the second level of KM maturity. Therefore, personalization strategies are proposed for this organization based on the elucidated paradigm. Moreover, development of work communities and development of face-to-face interactions among staff through continuous meetings were chosen as the most significant KM strategies in this organization.

Originality/value

This paper is one of the leading studies carried out in the purview of codification of KM strategies according to different organizations’ level of maturity. Results of this study might be used as guidelines by different organizations, academic people and experts intending to codify KM strategies.