bluuebunny/crossref_metadata_2025 huggingface dataset:
SPONTANEOUS CLOSURE OF A LARGE STAGE III MACULAR HOLE AFTER PANRETINAL PHOTOCOAGULATION IN A PATIENT WITH SEVERE PROLIFERATIVE DIABETIC RETINOPATHY
Authors: Kolomeyer Anton M. , Anetakis Alexander J.
Published: March 2016

Purpose:

To report spontaneous closure of a tractional Stage III macular hole (MH) in a patient with proliferative diabetic retinopathy (PDR) after panretinal photocoagulation (PRP).

Methods:

Case report of a 43-year-old man with poorly controlled Type I diabetes and bilateral severe proliferative diabetic retinopathy.

Results:

On presentation, visual acuity was 20/400 and fundus examination was significant for a Stage III tractional MH in the left eye. Vision in the right eye was light perception from neovascular glaucoma. Fluorescein angiography showed extremely severe macular and peripheral ischemia, disk neovascularization, and macular traction from fibroglial tissue. After 5 panretinal photocoagulation sessions over 3 months, the MH spontaneously closed; however, vision remained 20/400. Fluorescein angiography showed regressed disk neovascularization and mild diffuse macular leakage. After a 13-month loss to follow-up, he presented with 20/300 vision, and, despite extensive macular traction from fibroglial tissue, the MH remained closed. Owing to progressive traction from the fibroglial tissue, macular retinal detachment occurred and vision decreased to hand motions. The patient underwent pars plana vitrectomy, scar tissue removal, silicone oil tamponade, and laser. Postoperatively, visual acuity decreased to no light perception because of neovascular glaucoma complications and lack of proper follow-up.

Conclusion:

Spontaneous closure of a Stage III MH may occur in patients with PDR after PRP; however, it may not result in long-term visual improvement.
Highly accessible AU-rich regions in 3’ untranslated regions are hotspots for binding of proteins and miRNAs
Authors: Plass Mireya , Rasmussen Simon H. , Krogh Anders
Published: March 2016

Background

MicroRNAs (miRNAs) are endogenous short non-coding RNAs involved in the regulation of gene expression at the post-transcriptional level typically by promoting destabilization or translational repression of target RNAs. Sometimes this regulation is absent or different, which likely is the result of interactions with other post-transcriptional factors, particularly RNA-binding proteins (RBPs). Despite the importance of the interactions between RBPs and miRNAs, little is known about how they affect post-transcriptional regulation in a global scale.

Results

In this study, we have analyzed CLIP datasets of 49 RBPs in HEK293 cells with the aim of understanding the interplay between RBPs and miRNAs in post-transcriptional regulation. Our results show that RBPs bind preferentially in conserved regulatory hotspots that frequently contain miRNA target sites. This organization facilitates the competition and cooperation among RBPs and the regulation of miRNA target site accessibility. In some cases RBP enrichment on target sites correlates with miRNA expression, suggesting coordination between the regulatory factors. However, in most cases, competition among factors is the most plausible interpretation of our data. Upon AGO2 knockdown, transcripts that contain such hotspots that overlap target sites of expressed miRNAs in 3’UTRs are significantly less up-regulated than transcripts without them, suggesting that RBP binding limits miRNA accessibility.

Conclusions

We show that RBP binding is concentrated in regulatory hotspots in 3’UTRs. The presence of these hotspots facilitates the interaction among post-transcriptional regulators, that interact or compete with each other under different conditions. These hotspots are enriched in genes with regulatory functions such as DNA binding and RNA binding. Taken together, our results suggest that hotspots are important regulatory regions that define an extra layer of auto-regulatory control of post-transcriptional regulation.
Genetics of cortico-cerebellar expansion in anthropoid primates: a comparative approach
Authors: Harrison Peter W. , Montgomery Stephen H.
Published: March 2016

What adaptive changes in brain structure and function underpin the evolution of increased cognitive performance in humans and our close relatives? Identifying the genetic basis of brain evolution has become a major tool in answering this question. Numerous cases of positive selection, altered gene expression or gene duplication have been identified that may contribute to the evolution of the neocortex, which is widely assumed to play a predominant role in cognitive evolution. However, the neocortex co-evolves with other, functionally inter-dependent, regions of the brain, most notably the cerebellum. The cerebellum is linked to a range of cognitive tasks and expanded rapidly during hominoid evolution, independently of neocortex size. Here we demonstrate that, across primates, genes with known roles in cerebellum development are just as likely to be targeted by selection as genes linked to cortical development. In fact, cerebellum genes are more likely to have evolved adaptively during hominoid evolution, consistent with phenotypic data suggesting an accelerated rate of cerebellar expansion in apes. Finally, we present evidence that selection targeted genes with specific effects on either the neocortex or cerebellum, not both. This suggests cortico-cerebellar co-evolution is maintained by selection acting on independent developmental programs.
Adaptive divergence in brain composition between ecologically distinct incipient species
Authors: Montgomery Stephen H. , Merrill Richard M.
Published: March 2016

During ecological speciation diverging populations are exposed to contrasting sensory and spatial information that present new behavioral and perceptive challenges. Here, we investigate how brain composition evolves during the early stages of speciation. The incipient species pair,Heliconius erato cyrbiaandH. himera, have parapatric ranges across an environmental and altitudinal gradient. Despite continuing gene-flow, these species have divergent ecological, behavioral and physiological traits. We demonstrate that these incipient species also differ significantly in brain composition, especially in the size of sensory structures.H. eratohas larger visual components whilstH. himerainvests more heavily in olfaction. These differences are not explained by environmentally-induced plasticity, but reflect non-allometric shifts in brain structure. Our results suggest the adaptive evolution of brain structure and function play an important role in facilitating the emergence of ecologically distinct species, and imply that plasticity alone may be insufficient to meet the demands of novel environments.
Differential regulation of the anti-crossover and replication fork regression activities of Mph1 by Mte1
Authors: Xue Xiaoyu , Papusha Alma , Choi Koyi , Bonner Jacob N. , Kumar Sandeep , Niu Hengyao , Kaur Hardeep , Zheng Xiao-Feng , Donnianni Roberto A. , Lu Lucy , Lichten Michael , Zhao Xiaolan , Ira Grzegorz , Sung Patrick
Published: March 2016

We identified Mte1 (Mph1-associated telomere maintenance protein 1) as a multifunctional regulator of Saccharomyces cerevisiae Mph1, a member of the FANCM family of DNA motor proteins important for DNA replication fork repair and crossover suppression during homologous recombination. We show that Mte1 interacts with Mph1 and DNA species that resemble a DNA replication fork and the D loop formed during recombination. Biochemically, Mte1 stimulates Mph1-mediated DNA replication fork regression and branch migration in a model substrate. Consistent with this activity, genetic analysis reveals that Mte1 functions with Mph1 and the associated MHF complex in replication fork repair. Surprisingly, Mte1 antagonizes the D-loop-dissociative activity of Mph1–MHF and exerts a procrossover role in mitotic recombination. We further show that the influence of Mte1 on Mph1 activities requires its binding to Mph1 and DNA. Thus, Mte1 differentially regulates Mph1 activities to achieve distinct outcomes in recombination and replication fork repair.
Mte1 interacts with Mph1 and promotes crossover recombination and telomere maintenance
Authors: Silva Sonia , Altmannova Veronika , Luke-Glaser Sarah , Henriksen Peter , Gallina Irene , Yang Xuejiao , Choudhary Chunaram , Luke Brian , Krejci Lumir , Lisby Michael
Published: March 2016

Mph1 is a member of the conserved FANCM family of DNA motor proteins that play key roles in genome maintenance processes underlying Fanconi anemia, a cancer predisposition syndrome in humans. Here, we identify Mte1 as a novel interactor of the Mph1 helicase in Saccharomyces cerevisiae. In vitro, Mte1 (Mph1-associated telomere maintenance protein 1) binds directly to DNA with a preference for branched molecules such as D loops and fork structures. In addition, Mte1 stimulates the helicase and fork regression activities of Mph1 while inhibiting the ability of Mph1 to dissociate recombination intermediates. Deletion of MTE1 reduces crossover recombination and suppresses the sensitivity of mph1Δ mutant cells to replication stress. Mph1 and Mte1 interdependently colocalize at DNA damage-induced foci and dysfunctional telomeres, and MTE1 deletion results in elongated telomeres. Taken together, our data indicate that Mte1 plays a role in regulation of crossover recombination, response to replication stress, and telomere maintenance.
Marketing, economic growth, and competitive strategies of firms in Africa
Authors: Kuada John
Published: March 2016

Purpose

– The purpose of this paper is to examine the role of marketing in the economic growth and competitive strategies of Sub-Sahara African firms. It also seeks to offer a backdrop for the papers in the present volume of AJEMS.

Design/methodology/approach

– It is based on a review of a selection of literature that highlights past and current perspectives of marketing’s contribution to economic growth and firm performance in developing economies.

Findings

– The review suggests that trade liberalization in African countries since the 1980s has changed the competitive landscape of firms located in these countries and has compelled them to develop market-oriented strategies in order to enhance their performance. But the strategies adopted tend to target the growing middle income segments of the population in the urban areas and to ignore the poor.

Originality/value

– It provides directions for future research into issues of inclusive marketing policies and strategies – i.e. strategies that embrace the bottom of the pyramid and transforms the production base of African economies.
Correlates of the determinants of relationship marketing in the retail sector: the Nigerian case
Authors: Izogo Ernest Emeka , Ogba Ike-Elechi , Nwekpa Kenneth Chukwuma
Published: March 2016

Purpose

– The purpose of this paper is to explore the linkages between the determinants of relationship marketing and the behavioural component of these determinants within a non-Western retail stores setting.

Design/methodology/approach

– A quantitative approach was employed, using 19-item, seven-point Likert scaled questionnaire administered to 350 participants with 67 per cent usable response rate. Data was analysed using exploratory factor analysis, Cronbach’s α internal consistency; correlation analysis and One-Way Analysis of Variance test.

Findings

– Trust-Quality services emerged as the most outstanding determinant of relationship marketing within the retail stores context followed by relational orientation, commitment and proximity. Quality services were found to have the most significant positive impact on trust whereas trust was found to have a strong positive impact on commitment. Relational orientation was found to have a strong positive impact on trust, commitment and quality services but proximity was found to be a docile factor determining commitment and relational orientation. Finally, consumers were identified as being more relationally oriented than retailers and all categories of consumers can be served with same blend of relationship marketing strategies.

Research limitations/implications

– Since findings could not be generalized across other sectors and regions, guides for testing the proposed research model are put forward.

Practical implications

– Relationship marketing implementation within the context of retail stores will be more successful if based on delivery of quality services. Consumers are also more likely to patronize closer than distant retail stores. As such, even if retail firms build strong trust, commitment and relational orientation with customers through quality services, consumers will still patronize stores that are closer to them more than stores in distant locations. Siting retail stores in locations with the largest pool of customers’ is therefore central to enhancing retail stores performance. All categories of customers could be served with same stream of relationship marketing strategies because designing different schemes of relationship marketing programmes for different customer categories were found to be counter-productive.

Originality/value

– This paper identified 16 attributes that are important to consumers under four dimensions: Trust-Quality services, relational orientation, commitment and proximity within the retail stores context. The findings are acknowledged to be unique because they emerged from a largely under-researched collectivistic emerging market where relationship marketing formation is key.
Service fairness and customer behavioural intention
Authors: Narteh Bedman
Published: March 2016

Purpose

– The purpose of this paper is to examine the relationship between service fairness and behavioural intention and the moderating role of demographic variables among retail banking customers.

Design/methodology/approach

– A four-factor structure consisting of price, procedural, interaction and outcome fairness gleaned from the literature was adopted for the current study. This was used to survey 381 customers of 15 retail banks in Ghana. Exploratory factor analysis and hierarchical regression were used to analyse the hypothesized relationships among the factors.

Findings

– The paper found support for the existence of the four-factor structure of service fairness in the retail banking industry. The study also found that price, interaction, procedure and outcome fairness in order of importance significantly predict customer’s behavioural intention. In addition, age, education and income of customers were found to moderate the relationship between the dependent and independent variables.

Practical implications

– The focus of the study on Ghana and in the banking industry limits the generalizability of the findings. However, the four-factor structure identified could be replicated in other countries, thereby setting the stage for cross-country studies on service fairness in the retail banking industry.

Originality/value

– The paper extends the domain of the application of the four-factor structure of service fairness from restaurants to the retail banking industry. As such, it provides bank managers with a plausible framework on service fairness for managing relationship with customers in retail banks.
The determinants of service recovery in the retail industry
Authors: Crabbe Margaret J. , Acquaah Moses
Published: March 2016

Purpose

– Service recovery strategies are efforts used by organizations to bring back dissatisfied customers to a state of satisfaction with the organization. It has been argued that successful service recovery by organizations is dependent on the effectiveness of front line employees. The purpose of this paper is to examine a model of service recovery performance (SRP) of front line employees in the retail industry in Ghana.

Design/methodology/approach

– The study uses personally administered survey data collected from 136 employees in 20 micro and small retail enterprises in Ghana. Hierarchical multiple regression analysis is used to test the direct and interactive effects of organizational variables such as perceived managerial attitudes and work environment factors on the SRP of front line employees.

Findings

– The findings indicate that the SRP is influenced by employee empowerment, interaction between customer service orientation and empowerment, interaction between customer service orientation and training for customer service excellence, and the interaction between empowerment and training for customer service excellence.

Research limitations/implications

– Focussing only on the antecedents of SRP, and using cross-sectional data based on the self-assessments of the front line employees from one country.

Practical implications

– Empowering front line employees to deal with service failures should be combined with training them in job related and behavioral skills to attend to the needs of customers. Moreover, it is critical to combine perceived customer service orientation with training front line employees in job related and behavioral skills.

Originality/value

– First study to examine the antecedents of SRP of front line employees in a sub-Saharan African environment. Moreover, study examines the interactive effects of organizational and work environment variables on SRP.
Design of synchronous reluctance and permanent magnet synchronous reluctance machines for electric vehicle application
Authors: Guan Y. , Zhu Z.Q. , Afinowi I.A.A. , Mipo J.C. , Farah P.
Published: March 2016

Purpose

– The purpose of this paper is to minimize the optimization parameter number of synchronous reluctance machine (SynRM) and permanent magnet (PM) assisted SynRM, and compare their relative merits with interior permanent magnet (IPM) machine for electric vehicle applications, in terms of electromagnetic performance and material cost.

Design/methodology/approach

– The analysis of electromagnetic performance is based on finite element analysis, by using software MAXWELL. The genetic algorithm is utilized for optimization.

Findings

– The rotor design of SynRM can be significantly simplified by imposing some reasonable conditions. The number of rotor design parameters can be reduced to three. The electromagnetic performance of SynRM is much poorer than that of IPM, although the material cost is much cheaper, approximately one-third of IPM. The ferrite-SynRM is competitive and even better than IPM especially for high electric loading, in terms of torque capability, torque-speed characteristic, power factor, threshold speed and efficiency. In addition, ferrite-assisted SynRM has great advantage over IPM in material cost, 55 percent cheaper. The performance of NdFeB-assisted SynRM is close to IPM in terms of torque capability, torque-speed characteristic, power factor, torque ripple and efficiency. The material cost of NdFeB-assisted SynRM is ∼25 percent lower than IPM.

Originality/value

– Some conditions, which can simplify the optimization of SynRM rotor, are discussed. The electromagnetic performances and material costs of SynRM, ferrite-assisted, NdFeB-assisted SynRMs and IPM are quantitatively compared and discussed.
Switched-flux machines with hybrid NdFeB and ferrite magnets
Authors: Afinowi I.A.A. , Zhu Z.Q. , Guan Y. , Mipo Jean-Claude , Farah P.
Published: March 2016

Purpose

– The purpose of this paper is to comparatively study the conventional, i.e. single magnet, and novel hybrid-magnet switched-flux permanent-magnet (HMSFPM) machines.

Design/methodology/approach

– The HMSFPM machines utilize two magnet types, i.e. low-cost ferrites and NdFeB. Thus, a set of magnet ratios (?), defined as the quotient of the NdFeB volume to the total PM volume, is introduced. This allows any desired performance and cost trade-off to be designed. Series- and parallel-excited magnet configurations are investigated using 2-dimensional finite element analysis.

Findings

– The torque of the HMSFPM machines is lower than the NdFeB SFPM machine but the flux-weakening performance is improved for similar machine efficiency. If the machine dimensions are unconstrained, the HMSFPM machines can have the same torque for reduced material costs and a moderate increase in machine dimensions. Ferrite SFPM machines have the lowest cost for the same torque but a significant increase in machine dimensions is required. Finally, the series-excited HMSFPM machine is the preferred over the parallel-excited HMSFPM machine because it has superior demagnetization withstand capability.

Research limitations/implications

– Mechanical and winding eddy current losses are not considered in the efficiency map calculations.

Originality/value

– The NdFeB SFPM, ferrite SFPM, series-excited HMSFPM, and the parallel-excited HMSFPM machines are compared for their electromagnetic performance, flux-weakening, PM demagnetization, efficiency, and material costs.
Research on yokeless double-sided multi-tooth flux-switching linear motor
Authors: Lu Qinfen , Li Huanwen , Huang Xiaoyan , Ye Yunyue
Published: March 2016

Purpose

– Due to the advantages of direct driven, high thrust density, and high efficiency, flux-switching linear motor (FSLM) is required for many applications, including aerospace and automotive. However, the vibration caused by detent force and difficulties in the assembly produced by the large normal force become the barriers that restrict its development. The paper aims to discuss these issues.

Design/methodology/approach

– In order to improve the electromagnetic performance of double-sided multi-tooth FSLM (DMTFSLM), a yokeless DMTFSLM with moving primary is proposed and compared with normal DMTFSLM. Moreover, with theoretical analysis, the selection principle of slot-pole number combination is obtained. DMTFSLMs with four slot/pole combinations, 6s/16p, 6s/17p, 6s/19p, 6s/20p, are analyzed based on finite element analysis model. Finally, several parameters of this yokeless DMTFSLM have been optimized to obtain the better performance.

Findings

– In yokeless DMTFSLM, it is found that the asymmetry of Back-EMF caused by the end-effect is eliminated, which leads to a better thrust force performance in comparison with the normal structure. The small attractive force between the secondary and the primary makes it easier for assembly and also can reduce the friction, which is more suitable for high-speed application. In addition, the best slot-pole combination rule is found through a simple theoretical analysis.

Originality/value

– The yokeless DMTFSLM has excellent electromagnetic performance, such as high thrust density, negligible normal force, and small force ripple. It is a strong candidate for high-precision device.
Partitioned stator flux reversal machines having Halbach array PMs
Authors: Zheng M. , Wu Z.Z. , Zhu Z.Q.
Published: March 2016

Purpose

– In this paper, the partitioned stator flux reversal permanent magnet (PM) (PS-FRPM) machines with Halbach array PMs are investigated to compare with the machine having the conventional parallel magnetized PMs, and conventional FRPM machine. This paper aims to discuss these issues.

Design/methodology/approach

– The Halbach array PM machines with 2-, 3-, and 4-segment and ideal Halbach array PMs have similar topology and designed based on the PS-FRPM with parallel magnetized PMs. The open circuit analysis and electromagnetic performance has been calculated and compares with the aid of finite element (FE) method, and validated by experiments.

Findings

– The PS-FRPMs with Halbach array PMs have higher back-EMF and torque performance, as well as lower cogging torque and torque ripple, all having significantly higher torque density than the FRPM machine with single stator. The experimental results and FE predicted results of the 2-segment Halbach PM prototype machine are compared and good agreement is achieved.

Originality/value

– This paper introduces the new concept and design of PS-FRPMs having Halbach array PMs with different PM segments and idea PM array. The comparison with conventional FRPM and PS-FRPM with parallel magnetized PMs shows the benefits with PS-FRPMs with Halbach array PMs.
Thermal modeling and analysis of double-sided water-cooled permanent magnet linear synchronous machines
Authors: Chen Yi , Yao Yihua , Lu Qinfen , Huang Xiaoyan , Ye Yunyue
Published: March 2016

Purpose

– With the popularization of permanent magnet linear synchronous machines (PMLSMs) in recent years, the temperature rise has attracted increasingly attention since excessive heat generated in the windings could deteriorate the electromagnetic performance. In order to solve this problem, adopting water-cooled system is an effective method. The purpose of this paper is to investigate a 12-slot/11-pole (12S/11P) water-cooled double-sided PMLSM, which adopts the all teeth wound concentrated winding and shifted armature ends.

Design/methodology/approach

– Based on 2D finite element analysis (FEA), the thermal performances, such as temperature distribution, the optimization of water flow rate and the influence of demagnetization, are investigated under the condition of continuous duty. Then the maximum current density and average thrust force are calculated for PMLSMs with or without water-cooled system. Finally, the detailed comparison is made between single-sided PMLSM and double-sided PMLSM.

Findings

– With water-cooled system, the thermal performance of PMLSM can be improved, such as an efficient decrease of temperature rise, restriction of permanent magnet demagnetization and a dramatic increase of the maximum thrust force. It is found that the water flow rate has a significant impact on temperature rise, which can be optimized according to demands.

Originality/value

– Electromagnetic and thermal coupled analysis is proposed in this paper. It can approximately predict thermal performance and save the manual iteration time at the same time. This method also can provide as a reference of thermal analysis for other PMLSMs.
Analysis of thrust ripple harmonics on different electric loadings in PM linear synchronous machines with skewed PMs
Authors: Yao Yihua , Chen Yi , Lu Qinfen , Huang Xiaoyan , Ye Yunyue
Published: March 2016

Purpose

– Permanent magnet linear synchronous machines (PMLSMs) have large thrust ripple due to the longitudinal end effect caused by the finite length of the armature compared with rotary machines. The purpose of this paper is to analyze the influence of electric loading on thrust ripple performances based on a 12 slots/14 poles (12S/14P) PMLSM. Furthermore, the method of skewed PMs to reduce thrust ripple is investigated based on multi slices 2D finite element (FE) models.

Design/methodology/approach

– The thrust ripple of PMLSM under open-circuit condition results from the slotting and the longitudinal end effects. Therefore, periodical model has been designed to clarify the effect of the longitudinal end effect. Under on-load condition, the thrust ripple increases and exhibits an effective component of thrust force. To analyze the thrust ripple under on-load condition, frozen permeability (FP) technique is employed. In addition, the method of skewed PMs is analyzed in this paper to obtain more smooth thrust force performance. The effectiveness of skewing accounting for skew angles, step skew numbers and slot/pole number combinations was highlighted.

Findings

– The longitudinal end effect dominates the thrust ripple of PMLSM in both cases, i.e., open-circuit and on-load conditions. Under on-load condition, the second harmonic component of thrust ripple related to flux linkage harmonics increases significantly. Moreover, the effectiveness of skewed PMs is largely reduced with the increase of magnetic saturation. At last, a proper skew angle and step skew number are obtained for the conventional PMLSM with fractional-slot winding.

Originality/value

– By 60 electrical degrees and two or three step skewed PMs, the thrust ripple can be decreased to a tolerable limite for conventional PMLSM. The thrust ripple harmonics contributed by longitudinal end effect and flux linkage harmonics are analyzed, respectively, which is beneficial to exploring other techniques such as adding end auxiliary teeth to obtain lower thrust force pulsation.
Comparative study on synchronous reluctance and PM machines
Authors: Cai Shun , Jin Meng-Jia , Hao He , Shen Jian-Xin
Published: March 2016

Purpose

– The purpose of this paper is to comparatively study a synchronous reluctance machine (SynRM) and a permanent magnet assisted synchronous reluctance machine (PMASynRM) as alternatives of the interior permanent magnet synchronous machine (IPMSM), and to investigate the performance and conclude both advantages and disadvantages.

Design/methodology/approach

– A unified mathematical model is established for the IPMSM, SynRM and PMASynRM. Then finite element method (FEM) is used to compare the electromagnetic performance. Permeability-frozen method is utilized to distinguish basic electromagnetic torque and reluctance torque.

Findings

– The PMASynRM can improve the power factor of the SynRM, overcome the drawback of the IPMSM in the high-speed flux-weakening region and is more proper to operate over a wide speed region. The SynRM is mechanically robust for lacking of the permanent magnets, and the PMASynRM can keep similar rotor stress as the SynRM by optimizing the magnets. Assembly of the SynRM is the simplest, and the economic performance of the SynRM and PMASynRM could be much better than the IPMSM which even uses ferrite magnets.

Practical/implications

– The SynRM can produce identical torque and efficiency compared with the IPMSM except the poor power factor. The poor power factor could be improved by adopting the PMASynRM, which is proved to be able to act as an alternative of the IPMSM for low-cost high-performance application.

Originality/value

– This paper provides the theoretical model of the IPMSM, SynRM and PMASynRM in a unified format. The electromagnetic, mechanical and economic performances of the three kinds of synchronous motors are compared comprehensively. Then, both the advantages and disadvantages are summarized.
DTC of reconfigured three level inverter fed IM drives following a leg failure
Authors: Gallah Tarek , Bouzidi Badii , Masmoudi Ahmed
Published: March 2016

Purpose

– The purpose of this paper is to deal the adaptation of a direct torque control (DTC) strategy, originally dedicated to three level three leg inverter fed induction motor (IM) drives, following a leg failure that required the reconfiguration of the inverter from three to two legs.

Design/methodology/approach

– In case of troubles with one leg of a three level inverter, it is interesting in some applications to keep operating using the two remaining legs. So, after the detection and isolation of the faulty leg, the drive connection should be rearranged with the connection of the motor phase, previously linked to the faulty leg, to the mid point of the DC-bus voltage, leading to a three level two leg inverter topology (also called bridge B8-inverter).

Findings

– It has been found that the IM drive exhibits better performances under the proposed DTC strategy dedicated to the reconfigured inverter than those yielded by the DTC of the IM drive under healthy operation of the inverter. It has been noticed that the only drawback affecting the reconfigured inverter fed IM drive is the speed range limitation.

Research limitations/implications

– This work should be extended by an experimental validation of the proposed DTC strategies.

Originality/value

– The power factor of the reconfigured three level inverter fed IM drive is higher than the one yielded by the three level three leg inverter fed one. This represents a crucial cost benefit.
The efficiency characteristics analysis and optimization of the magnetic resonance wireless power transmission to multiple receivers
Authors: Zhou Jing , Gao Yuqing , Huang Xiaoyan , Fang Youtong
Published: March 2016

Purpose

– Consider the mutual coupling between loads, the purpose of this paper is to study the total transmission efficiency based on different load coil positions relative to the charging platform, to provide the theoretical basis for the design and parameter optimization of one-to-multiple wireless charging platform.

Design/methodology/approach

– Based on the dual-load series-resonant wireless power transfer system, the expression of system efficiency and its calculation model is achieved using the equivalent circuit theory. Finally, a 96 kHz magnetic resonance wireless power transmission test platform is built up to verify the theoretical analysis given in this paper.

Findings

– For the completely resonant circuit, the transmission efficiency can be improved by increasing the transmitter-receiver coupling and reducing the coupling between receivers. The total transmission efficiency achieves its lowest value when two loads are with equal competitive capability.

Originality/value

– Through the simulation analysis of efficiency formula, the selection principle of impact factors can be applied to the optimization analysis of the transmission efficiency.
Perceptions of trust in the US construction industry
Authors: Zuppa Dino , Olbina Svetlana , Issa Raymond
Published: March 2016

Purpose

– The purpose of this paper is to obtain an understanding of the perception of trust between US construction contracting parties. The research objectives were to identify the factors on construction projects that impact such trust and to identify how trust affects factors on construction project.

Design/methodology/approach

– A survey of construction professionals working for the Engineering News Record’s Top 400 US contractors was conducted.

Findings

– The findings showed that paying on time, competency, reliability and effective collaboration were the most important factors that affected contextual conditions trustworthiness. Factors perceived to strengthen trust included face-to-face communication, electronic documents, and timely and adequate responses to requests for information. The presence of construction managers on construction projects, and corrective changes orders from neutral third parties were perceived to weaken trust. Trust was perceived to assist leadership, team building, communication and information sharing.

Originality/value

– The main contribution of this study is the discovery of additional factors that impact trust and factors that require trust and that were not identified by previous researchers.
Formal ties in financial networks: professional clusters in financial services marketing
Authors: Borg Erik , Vigerland Lars , Winroth Karin
Published: March 2016

Purpose

– The purpose of this paper is to investigate the role of formal ties in the marketing of financial services and thus provide evidence concerning the relationship between formal ties and the customer appeal of banks and investment banks.

Design/methodology/approach

– The paper uses correspondence analysis to study formal ties between financial market actors and relates them to customer rankings. The formal ties are described as intra-, inter- and extra-organizational ties.

Findings

– The authors find that there are several formal ties between financial market actors and provide compelling evidence illustrating how the attractions between financial service providers are related in several ways to the existence of formal ties between market actors.

Research limitations/implications

– The research is limited to formal, as opposed to informal, ties. The authors examine the essential implications of such ties.

Practical implications

– In practice, banks and investment banks should consider the implications of formal ties and market connections to improve their performance.

Social implications

– Networking is a tool for the marketing of financial services and should be understood as such.

Originality/value

– The originality of this study consists in showing the relevance of various attributes in studying networks in financial markets and in contributing to an understanding of social attributes and formal organization.
Exploring the relationship among servant leadership, intrinsic motivation and performance in an industrial sales setting
Authors: Bande Belén , Fernández-Ferrín Pilar , Varela-Neira Concepción , Otero-Neira Carmen
Published: March 2016

Purpose

– Although servant leadership (SL) improves the overall effectiveness of individuals and teams, it remains understudied. The aim of this paper is to provide insight into the mediating mechanisms through which perceived SL affects salespersons’ proactive and adaptive behaviors.

Design/methodology/approach

– Data were gathered from 145 industrial salespeople and their supervisors across a variety of businesses and sectors in Spain.

Findings

– SL enhances salespeople’s adaptivity and proactivity by positively affecting their self-efficacy and intrinsic motivation. Furthermore, SL directly shapes the development of adaptive behaviors among salespeople, although this direct influence is not significant when considering proactivity. Additionally, the use of outcome-based control mechanisms enhances the positive effects of SL on salespeople’s intrinsic motivation.

Practical implications

– The results demonstrate that sales managers can promote more proactive and adaptive behaviors among sales staff by recognizing the importance of service and their moral responsibilities to the success of their subordinates.

Originality/value

– Cognitive evaluation theory was used to examine the direct and indirect effects of perceived SL on two emergent change-oriented behaviors (adaptivity and proactivity) using a matched sample of industrial salespeople from a variety of industries, thus providing a basis for the generalization of results. Moreover, in analyzing the moderating effects of outcome control, the conditions under which SL is more or less effective were examined.
Types of embedded ties in buyer-supplier relationships and their combined effects on innovation performance
Authors: Charterina Jon , Basterretxea Imanol , Landeta Jon
Published: March 2016

Purpose

– This paper aims to analyze the impact of three types of embedded ties, namely, specialized complementary resources, idiosyncratic investments and knowledge sharing, on the innovation capacity of firms. It also examines the particularities of the machine-tool industry.

Design/methodology/approach

– The evaluation of the embedded buyer-supplier ties is based on the potential sources of relational rents proposed by Dyer and Singh (1998). It also draws on Uzzi and Lancaster (2003) and Noordhoffet al.(2011), among others, to discuss the positive and negative aspects of embedded ties. Using data from a survey of 202 European machine-tool firms acting as buyers and sellers, the study proposes and evaluates a structural equation model.

Findings

– Only knowledge-sharing routines exert a significant positive effect on product innovation performance. Neither an increase in idiosyncratic investments nor in complementary resources and capabilities enhances innovation performance. Moreover, knowledge-sharing routines mediate in the effect of idiosyncratic investments on innovation performance.

Research limitations/implications

– The machine-tool industry has unique characteristics that make generalization difficult. There is also considerable difficulty associated with testing the interrelations among these embedded ties in greater depth in the long run. It is plausible to consider that these interrelations operate within a gradual process.

Originality/value

– This research contributes to a better understanding of the role of embedded ties on innovativeness. To the best of the authors’ knowledge, no previous international empirical research has been published analyzing the mediation effects among specialized complementary resources, idiosyncratic investments and knowledge sharing, and their effects on the innovation capacity of firms.
Determinants of brand relevance in a B2B service purchasing context
Authors: Gomes Mariana , Fernandes Teresa , Brandão Amélia
Published: March 2016

Purpose

– Brands have traditionally been regarded as a key asset and a source of competitive advantage in purchasing decisions, as customers are expected to prefer stronger brands to minimize risks. However, the role of brands in business markets is unclear and underresearched. The purpose of this study is to analyze the relevance of brands in a business-to-business (B2B) purchase setting and their key determinants.

Design Methodology/approach

– A research model was developed to explain brand relevance when compared with other decision factors in a B2B context. Based on the frameworks developed by Zablah et al. (2010) and Mudambi (2002), the model considers the purchase situation, decision-maker characteristics and firm size as determinants of brand relevance in the decision-making process. One of the most prominent Portuguese construction groups, which comprised three companies, was chosen for the sample of this study. Data were collected through a self-administered, online, cross-sectional survey, resulting in a convenience sample of 87 decision-makers.

Findings

– Findings suggest that attributes related with brands matter even in B2B rational decision-making processes. However, brands are not important to all organizational buyers or in all situations. Different purchase situations and decision-maker characteristics proved to have an impact on brand relevance, namely, brand reputation, prior purchases and brand awareness. Only firm size was not confirmed as a determinant of brand relevance in the B2B purchasing process.

Originality/value

– B2B brand research is scarce, especially for industrial services. By investigating the determinants of brand relevance in a B2B purchasing context, namely, in a construction services setting, this study contributes to bridging this literature gap. Moreover, the few studies on the subject have been largely descriptive in nature and managerially oriented, while this investigation emphasizes hypothesis testing through a proposed research framework. Also, in managerial terms, identifying determinants of the importance given to brands by organizational buyers is critical in deciding when investment in brand development is more likely to payoff.
The effect of green purchasing on purchasing performance: the moderating role played by long-term relationships and strategic integration
Authors: González-Benito Javier , Lannelongue Gustavo , Ferreira Luis Miguel , Gonzalez-Zapatero Carmen
Published: March 2016

Purpose

– The purpose of this paper is to analyse the relationship between the environmental management of purchases and firm performance. The authors examine the moderating role played by two variables: the establishment of long-term relationships with suppliers and the strategic integration of the purchasing function.

Design/methodology/approach

– The authors conduct an empirical study on a sample of 100 Portuguese firms.

Findings

– Evidence reveals that green purchasing management improves the performance of the purchasing function, although the impact is greater when the organisation forges lasting alliances with its suppliers.

Originality/value

– This paper contributes to the study of the consequences of introducing environmental practices into the purchasing function, especially with regards to the formation of a panel of sustainable suppliers. Specifically, this research provides evidence to show that the implementation of those practices has positive impacts on the operating performance of the purchasing function and that the said effect is greater when a firm establishes long-term relationships with its suppliers.
Gendering of commercial justice – experience of self-employed women in urban Tanzania
Authors: Tillmar Malin
Published: March 2016

Purpose

– Women’s entrepreneurship is often seen as the solution of both economic growth and gender equality. This is despite academic knowledge of the gendered preconditions for entrepreneurship in many contexts. This paper aims to focus on the gendering of commercial justice, a precondition for entrepreneurship. Informed by gender perspectives on women’s entrepreneurship and previous studies on commercial justice in East Africa, this paper sets out to explore the experiences of urban women entrepreneurs.

Design/methodology/approach

– The paper is based on an interview study with women entrepreneurs and representatives of support organizations in Dar-es-Salaam, Tanzania. The interviews were conducted in Kiswahili, and access was enabled through dialogues with local partner organizations such as the Tanzanian Chamber of Commerce.

Findings

– Findings are that with formal legal rights, the informal institutions imply that the marital status of the women, and the attitude of their husbands, is the overarching determinants for the commercial justice perceived as available to them. This has implication for many policy areas, such as entrepreneurship support, women’s empowerment and labour market policy. Theoretically, the findings highlight the importance of studying the informal institutions affecting women’s entrepreneurship around the globe. Concerning commercial justice in particular, three dimensions of gendering are identified.

Research limitations/implications

– The paper is based on a qualitative interview study. Further studies with varying methods are needed to further explore the gendering of commercial justice in Tanzania, East Africa and beyond.

Practical implications

– A major practical implication of the study is the insight that business for development, will not automatically lead to business for equality, on a general level. The gender bias is also reproduced in everyday business life, for example, thorough access to commercial justice. Special measures to target the gender equality issue are, therefore, necessary. Another implication of the findings regard the importance of Alternative Dispute Resolution initiatives, affordable to women small and medium enterprise-owners.

Originality/value

– While other obstacles to women’s entrepreneurship in the developing contexts have been well explored, the gendering of perceived commercial justice has not received sufficient attention in previous studies. Studies applying a gender theoretical perspective on entrepreneurship in the explored context are still needed.