bluuebunny/crossref_metadata_2025 huggingface dataset:
Romulus: robust multi-state identification
of transcription factor binding sites from
DNase-seq data
Authors: Jankowski Aleksander , Tiuryn Jerzy , Prabhakar Shyam
Published: April 2016

Motivation: Computational prediction of transcription factor (TF) binding sites in the genome remains a challenging task. Here, we present Romulus, a novel computational method for identifying individual TF binding sites from genome sequence information and cell-type–specific experimental data, such as DNase-seq. It combines the strengths of previous approaches, and improves robustness by reducing the number of free parameters in the model by an order of magnitude.

Results: We show that Romulus significantly outperforms existing methods across three sources of DNase-seq data, by assessing the performance of these tools against ChIP-seq profiles. The difference was particularly significant when applied to binding site prediction for low-information-content motifs. Our method is capable of inferring multiple binding modes for a single TF, which differ in their DNase I cut profile. Finally, using the model learned by Romulus and ChIP-seq data, we introduce Binding in Closed Chromatin (BCC) as a quantitative measure of TF pioneer factor activity. Uniquely, our measure quantifies a defining feature of pioneer factors, namely their ability to bind closed chromatin.

Availability and Implementation: Romulus is freely available as an R package at http://github.com/ajank/Romulus .

Contact:  ajank@mimuw.edu.pl

Supplementary information:  Supplementary data are available at Bioinformatics online.
Development of polymer–fullerene solar cells
Authors: Zhang Fengling , Inganäs Olle , Zhou Yinhua , Vandewal Koen
Published: April 2016

Global efforts and synergetic interdisciplinary collaborations on solution-processed bulk-heterojunction polymer solar cells (PSCs or OPVs) made power conversion efficiencies over 10% possible. The rapid progress of the field is credited to the synthesis of a large number of novel polymers with specially tunable optoelectronic properties, a better control over the nano-morphology of photoactive blend layers, the introduction of various effective interfacial layers, new device architectures and a deeper understanding of device physics. We will review the pioneering materials for polymer–fullerene solar cells and trace the progress of concepts driving their development. We discuss the evolution of morphology control, interfacial layers and device structures fully exploring the potential of photoactive materials. In order to guide a further increase in power conversion efficiency of OPV, the current understanding of the process of free charge carrier generation and the origin of the photovoltage is summarized followed by a perspective on how to overcome the limitations for industrializing PSCs.
First-principles design of spintronics materials
Authors: Li Xingxing , Yang Jinlong
Published: April 2016

Spintronics is one of the most promising next generation information technology, which uses the spins of electrons as information carriers and possesses potential advantages of speeding up data processing, high circuit integration density, and low energy consumption. However, spintronics faces a number of challenges, including spin generation and injection, long distance spin transport, and manipulation and detection of spin orientation. In solving these issues, new concepts and spintronics materials were proposed one after another, such as half metals, spin gapless semiconductors, and bipolar magnetic semiconductors. Topological insulators can also be viewed as a special class of spintronics materials, with their surface states used for pure spin generation and transportation. In designing these spintronics materials, first-principles calculations play a very important role. This article attempts to give a brief review of the basic principles and theoretical design of these materials. Meanwhile, we also give some attentions to the antiferromagnetic spintronics, which is mainly based on antiferromagnets and has aroused much interest in recent years.
An effective selection method for low-mass active black holes and first spectroscopic identification
Authors: Morokuma Tomoki , Tominaga Nozomu , Tanaka Masaomi , Yasuda Naoki , Furusawa Hisanori , Taniguchi Yuki , Kato Takahiro , Jiang Ji-an , Nagao Tohru , Kuncarayakti Hanindyo , Morokuma-Matsui Kana , Ikeda Hiroyuki , Blinnikov Sergei , Nomoto Ken'ichi , Kokubo Mitsuru , Doi Mamoru
Published: April 2016

We present a new method for effectively selecting objects which may be low-mass active black holes (BHs) at galaxy centers using high-cadence optical imaging data, and our first spectroscopic identification of an active 2.7 × 106 M⊙ BH at z = 0.164. This active BH was originally selected due to its rapid optical variability, from a few hours to a day, based on Subaru Hyper Suprime-Cam g-band imaging data taken with a 1 hr cadence. Broad and narrow Hα lines and many other emission ones are detected in our optical spectra taken with Subaru FOCAS, and the BH mass is measured via the broad Hα emission line width (1880 km s−1) and luminosity (4.2 × 1040 erg s−1) after careful correction to the atmospheric absorption around 7580–7720 Å. We measure the Eddington ratio and find it to be as low as 0.05, considerably smaller than those in a previous SDSS sample with similar BH mass and redshift, which indicates one of the special potentials of our Subaru survey. The g − r color and morphology of the extended component indicate that the host galaxy is a star-forming galaxy. We also show the effectiveness of our variability selection for low-mass active BHs.
PRECL: A new method for interferometry imaging from closure phase
Authors: Ikeda Shiro , Tazaki Fumie , Akiyama Kazunori , Hada Kazuhiro , Honma Mareki
Published: April 2016

For short-wavelength VLBI observations, it is difficult to measure the phase of the visibility function accurately. The closure phases are reliable measurements under this situation, though it is not sufficient to retrieve all of the phase information. We propose a new method, phase retrieval from closure phase (PRECL). PRECL estimates all the visibility phases only from the closure phases. Combining PRECL with a sparse modeling method we have already proposed, the imaging process of VLBI does not rely on a dirty image or self-calibration. The proposed method is tested numerically and the results are promising.
A modified Bernese periacetabular osteotomy suitable for less experienced surgeons and underequipped hospitals
Authors: Emara Khaled M. , Ghafar KhaledAbd E.L. , Diab Ramy Ahmed , Tawfik Noha
Published: April 2016

Background:

The classic Bernese periacetabular osteotomy is technically demanding, requires special surgical instruments, and requires increased radiation exposure during the procedure. We describe a modified technique for this osteotomy that is easier and requires no special surgical instruments and only minimal intraoperative radiation exposure.

Methods:

Twenty patients with acetabular dysplasia underwent our modified technique through a posterior hip approach that included a trochanteric osteotomy and superior pubic ramus osteotomy through a limited anterior approach. The osteotomy cuts were performed under direct vision.

Results:

The change in the acetabular inclination ranged from 5 to 19 degrees; the change in anterior and lateral center edge angles ranged from 14 to 42 degrees and 20 to 38 degrees, respectively. The procedure provided medial translation of the hip center with an average change of 6 mm. Clinical outcome analysis showed pain relief and improved hip function in 17 patients with improvement in the Harris Hip Score ranging from 15-25 points. Three patients did not show improvement of hip function, with sciatic nerve injury occurring in one patient, which recovered spontaneously after 6 wk, and delayed union of the trochanteric osteotomy in two patients.

Conclusions:

Our technique of performing periacetabular osteotomy through a posterior hip approach and limited anterior approach carries some disadvantages to the patient (risks of injury to the blood supply of the femoral head, heterotopic ossification, and complications of trochanteric osteotomy), but it is an easier technique that does not require special surgical instruments, and minimizes the need for intraoperative fluoroscopy, making it suitable for under-equipped centers and for the less experienced surgeons.
Complications in diabetic patients undergoing revision total joint arthroplasty
Authors: Mazoch Mathew , Barnes C. Lowry , Cooper Kasa
Published: April 2016

Background:

The risks of complications in individuals with diabetes undergoing primary total joint arthroplasty are well discussed in the literature; however, little is written about their risks with revision procedures. This study evaluates complications surrounding revision arthroplasty in diabetics compared with controls.

Methods:

Six hundred and thirty-five patients underwent revision total hip and knee surgery since 2004. Sixty-five diabetics who underwent revision arthroplasty were compared to 65 matched controls. Demographics, comorbidities, and hemoglobin A1c (HgbA1c) levels were analyzed in comparison to complications encountered.

Results:

Of the 635 revision arthroplasty patients sampled, 10.2% (65/635) of patients had both diabetes and HgbA1c levels drawn. Thirty (46%) diabetic patients experienced 58 complications and required 25 additional procedures. Twenty-three (35%) controls experienced 35 complications and had 22 additional procedures. HgbA1c levels were a median (quartiles) of 5.90 (5.60–6.40) among diabetics without a complication, compared to 6.55 (6.10–7.20) among diabetics with at least one complication (P=0.0006). The number of complications was also strongly correlated with patient’s HbA1c (Spearman’s rho=0.417; P=0.0009). Diabetic patients had a higher complication rate and number of complications than controls. Diabetic patients were at higher risk of developing infections (18.4% vs. 4.6%; P=0.025), periprosthetic fractures (9.2% vs. 0%; P=0.028), and more severe rare complications (P=0.0029).

Conclusions:

The study suggests that diabetics with better glycemic control tend to have fewer complications. Diabetics undergoing revision arthroplasty appear to be at a higher risk of developing infections, periprosthetic fractures, and rare events than nondiabetics.
Clinicopathologic Analysis of Stable and Unstable Vitiligo: A Study of 66 Cases
Authors: Yadav Amit Kumar , Singh Priyanka , Khunger Niti
Published: April 2016

Vitiligo is an acquired skin disorder characterized by milky-white macules and absence of functioning melanocytes. The cornerstone of its management is the correct categorization of a case into its 2 broad types—stable and unstable vitiligo. This distinction is at present based mainly on clinical criteria because the histopathological features are not fully established. This study was thus undertaken to examine histopathological features of vitiligo and to come up with a reliable and systematic approach toward this diagnostic challenge. All patients presenting with clinical features of vitiligo at our institution were included in the study. A 3-mm punch biopsy was taken from 3 sites—lesional, perilesional, and normal skin. Histopathological examination was primarily focused on evaluating 5 histopathological variables—spongiosis, epidermal lymphocytes, basal cell vacuolation, dermal lymphocytes, and melanophages. A total number of 66 patients were included in the study. There were 30 patients in stable and 36 in unstable vitiligo groups. It was observed that all 5 histopathological pattens were associated with unstable vitiligo. All the cases were then scored using a scoring system devised by the authors and the scores obtained were correlated with clinical categorization. It was observed that while there is a definite overlap in histological findings in the 2 groups, adoption of a systematic reporting system brings more consistency and objectivity in the diagnosis. The authors have recommended diagnoses that should be reported for the various scores. This in turn will help us to more reliably and confidently manage these patients.
Blue Nevus–Like Metastasis of a Cutaneous Melanoma Identified by Fluorescence In Situ Hybridization
Authors: Campa Molly , Patel Mahir , Aubert Pamela , Hosler Gregory , Witheiler Daniel
Published: April 2016

A blue nevus–like melanoma is a rare melanoma variant arising from or histologically similar to a blue nevus. It can be challenging to distinguish a cellular blue nevus from a blue nevus–like melanoma, particularly in cases of blue nevus–like melanoma lacking a transition from a clearly benign component. We present a case of a 78-year-old man who refused treatment for a previously existing melanoma and subsequently developed a gray nodule near the site of the previous melanoma. After fluorescence in situ hybridization revealed copy number gains in RREB1, this was diagnosed as a blue nevus–like metastatic melanoma. Blue nevus–like metastatic melanoma is most commonly seen near the site of the primary cutaneous melanoma. This entity should be considered in a patient with a history of melanoma and a new blue nevus–like lesion.
MALIGNANT TRANSFORMATION OF A CHOROIDAL NEVUS IN AN EYE TREATED FOR CHOROIDAL MELANOMA
Authors: Fabian Ido D. , Arora Amit K. , Cohen Victoria M. L.
Published: April 2016

Purpose:

To report a case of a choroidal melanoma and a discrete choroidal nevus that has transformed into a malignant melanoma 5 years after initial diagnosis.

Methods:

Retrospective case report.

Results:

A diffuse macular choroidal melanoma and a discrete choroidal nevus located superonasal to the optic disk were diagnosed in the right eye of a 63-year-old woman in 2009. The patient was treated by ruthenium plaque radiotherapy for the choroidal melanoma, which consequently flattened and scarred. On a routine eye check in 2014, the nevus was found to have been transformed into a choroidal melanoma. It was treated with ruthenium plaque radiotherapy.

Conclusion:

Although extremely rare, patients with a uveal melanoma can develop an additional discrete uveal melanoma. This case highlights the importance of monitoring benign choroidal nevi in patients with a history of choroidal melanoma.
Combining genetic and distributional approaches to sourcing introduced species: a case study on the Nile monitor (Varanus niloticus) in Florida
Authors: Dowell Stephanie A. , Wood Jared P. , Campbell Todd S. , Kolokotronis Sergios-Orestis , Hekkala Evon R.
Published: April 2016

Three separate breeding populations of the Nile monitor (Varanus niloticus) have been identified in Florida, USA, located in Cape Coral, West Palm Beach and Homestead Air Reserve Base. This large, predatory lizard could have negative effects on Florida's native wildlife. Here, we infer the source of the introduced populations using genetic and statistical approaches, as well as estimate the potential non-native distribution ofV. niloticusin North America. We collected genetic data from 25 Florida individuals as well as utilized genetic datasets from reference individuals spanning the full native distribution throughout sub-Saharan Africa. Using occurrence data from the inferred source population and the full species range, we built ecological niche models (ENMs) and projected them onto North America to determine regions with suitable climate. Our results indicated that the introduced populations resulted from three separate introduction events, and all originated from the southern coastal region of West Africa. The ENM built from the West African source population predicted only the southernmost portions of North America to be suitable. Conversely, the model derived from the full species’ range predicted suitable climates across a large portion of the United States. This information can be used to focus management and eradication efforts.
Microelastic mapping of the rat dentate gyrus
Authors: Luque Tomás , Kang Michael S. , Schaffer David V. , Kumar Sanjay
Published: April 2016

The lineage commitment of many cultured stem cells, including adult neural stem cells (NSCs), is strongly sensitive to the stiffness of the underlying extracellular matrix. However, it remains unclear how well the stiffness ranges explored in culture align with the microscale stiffness values stem cells actually encounter within their endogenous tissue niches. To address this question in the context of hippocampal NSCs, we used atomic force microscopy to spatially map the microscale elastic modulus (
E
) of specific anatomical substructures within living slices of rat dentate gyrus in which NSCs reside during lineage commitment
in vivo
. We measured depth-dependent apparent
E
-values at locations across the hilus (H), subgranular zone (SGZ) and granule cell layer (GCL) and found a two- to threefold increase in stiffness at 500 nm indentation from the H (49 ± 7 Pa) and SGZ (58 ± 8 Pa) to the GCL (115 ± 18 Pa), a fold change in stiffness we have previously found functionally relevant in culture. Additionally,
E
exhibits nonlinearity with depth, increasing significantly for indentations larger than 1 µm and most pronounced in the GCL. The methodological advances implemented for these measurements allow the quantification of the elastic properties of hippocampal NSC niche at unprecedented spatial resolution.
Do grandparents compete with or support their grandchildren? In Guatemala, paternal grandmothers may compete, and maternal grandmothers may cooperate
Authors: Sheppard Paula , Sear Rebecca
Published: April 2016

Previous research has found that the presence of grandparents, particularly grandmothers, is often positively associated with child survival. Little research has explored the potential mechanisms driving these associations. We use data from rural Guatemala to test whether contact with and direct investment (advice and financial) from grandparents is associated with child health, proxied by height. Our results demonstrate the complexity of family relationships and their influence on child health, suggesting that both cooperative and competitive relationships exist within the family. The clearest evidence we find for grandparental influence is that having a living paternal grandmother tends to be
negatively
associated with child height. By contrast, contact with maternal kin appears broadly to be beneficial for child height, although these relationships are weaker. These patterns are mirrored in maternal body mass index, suggesting grandparental influence acts partly through maternal health. These findings support the hypotheses that, under conditions of limited resources, family relationships may be competitive within the family lineage which shares the same resource base, but cooperative when there are few costs to cooperation. Finally, financial assistance from maternal grandfathers is positively correlated with infant length but negatively with the height of older children, perhaps because the receipt of financial support is an indication of need. The provision of advice shows no associations with child height.
Lattice continuum and diffusional creep
Authors: Mesarovic Sinisa Dj.
Published: April 2016

Diffusional creep is characterized by growth/disappearance of lattice planes at the crystal boundaries that serve as sources/sinks of vacancies, and by diffusion of vacancies. The lattice continuum theory developed here represents a natural and intuitive framework for the analysis of diffusion in crystals and lattice growth/loss at the boundaries. The formulation includes the definition of the Lagrangian reference configuration for the newly created lattice, the transport theorem and the definition of the creep rate tensor for a polycrystal as a piecewise uniform, discontinuous field. The values associated with each crystalline grain are related to the normal diffusional flux at grain boundaries. The governing equations for Nabarro–Herring creep are derived with coupled diffusion and elasticity with compositional eigenstrain. Both, bulk diffusional dissipation and boundary dissipation accompanying vacancy nucleation and absorption, are considered, but the latter is found to be negligible. For periodic arrangements of grains, diffusion formally decouples from elasticity but at the cost of a complicated boundary condition. The equilibrium of deviatorically stressed polycrystals is impossible without inclusion of interface energies. The secondary creep rate estimates correspond to the standard Nabarro–Herring model, and the volumetric creep is small. The initial (primary) creep rate is estimated to be much larger than the secondary creep rate.
Energetic differences between bacterioplankton trophic groups and coral reef resistance
Authors: McDole Somera Tracey , Bailey Barbara , Barott Katie , Grasis Juris , Hatay Mark , Hilton Brett J. , Hisakawa Nao , Nosrat Bahador , Nulton James , Silveira Cynthia B. , Sullivan Chris , Brainard Russell E. , Rohwer Forest
Published: April 2016

Coral reefs are among the most productive and diverse marine ecosystems on the Earth. They are also particularly sensitive to changing energetic requirements by different trophic levels. Microbialization specifically refers to the increase in the energetic metabolic demands of microbes relative to macrobes and is significantly correlated with increasing human influence on coral reefs. In this study, metabolic theory of ecology is used to quantify the relative contributions of two broad bacterioplankton groups, autotrophs and heterotrophs, to energy flux on 27 Pacific coral reef ecosystems experiencing human impact to varying degrees. The effective activation energy required for photosynthesis is lower than the average energy of activation for the biochemical reactions of the Krebs cycle, and changes in the proportional abundance of these two groups can greatly affect rates of energy and materials cycling. We show that reef-water communities with a higher proportional abundance of microbial autotrophs expend more metabolic energy per gram of microbial biomass. Increased energy and materials flux through fast energy channels (i.e. water-column associated microbial autotrophs) may dampen the detrimental effects of increased heterotrophic loads (e.g. coral disease) on coral reef systems experiencing anthropogenic disturbance.
Branded app implementation at the London Symphony Orchestra
Authors: Gosling Victoria , Crawford Garry , Bagnall Gaynor , Light Ben
Published: April 2016

Purpose

– The purpose of this paper is to consider the key findings of a yearlong collaborative research project focusing on the London Symphony Orchestra’s development, implementation and testing of a branded smartphone app. This app was designed to primarily sell discounted tickets, engage and inform a student audience.

Design/methodology/approach

– A mixed-method approach including an analysis of the technology, focus groups and interviews was used.

Findings

– Though the aims of app developers and marketers are often to provide customers with more choice and interactivity, this research suggests that though the app proved a useful mechanism for selling discounted tickets, it indicates that existing customers were mostly enroled and mobilised via a limited and focused functionality for the app.

Originality/value

– This paper is significant as mobile phone use remains comparatively under-researched, in particular there is still a relatively small literature on the growing phenomena of apps, and even less on their use in brand marketing. Also importantly, though this paper offers a consideration of one case, the app has since been expanded to include the ticketing for ten major orchestras in London, and moreover, many of the lessons learnt from this study will be of relevance to other arts organisations.
eWOM in the performing arts: exploratory insights for the marketing of theaters
Authors: Hausmann Andrea , Poellmann Lorenz
Published: April 2016

Purpose

– Word of mouth (WOM) plays an important role for the decision process of customers. This is especially interesting for service-dominant organizations like theaters where quality is more difficult to evaluate. In times of social media, third party recommendations can be given much more quickly, effectively and in greater detail. However, up to now not much has been researched on electronic word of mouth (eWOM) in a performing arts marketing context. The purpose of this paper is to provide some first exploratory insights into this research area.

Design/methodology/approach

– To do so, a literature review is conducted to clarify the concept of eWOM and the relevance of recommendations in the performing arts. Then, parts of the results of an online survey on Facebook with 16 German theaters and their fans will be presented. Finally, the implications of the study results for theater marketing are considered and ideas for future research are discussed.

Findings

– The study results confirm that recommendations have a high relevance for theatergoers and are very relevant in a social media context. They also show that the trustworthiness of eWOM on social media depends on the familiarity between the message sender and receiver. However, the results are limited with regard to the research design. Therefore, this paper concludes with ideas for further research.

Originality/value

– All in all, though the study’s focus is narrow, this paper fills a research gap in the performing arts. In doing so, the understanding of the phenomenon and its importance for arts marketing will be enhanced.
How are arts organizations responding to critique in the digital age?
Authors: Wiggins Johnson Jennifer , Preece Stephen B. , Song Chanho
Published: April 2016

Purpose

– Online communications have made critical reviews widely accessible, enabled a broader range of opinions to be heard, and led to increased critical dialogue among audiences. The purpose of this paper is to investigate how arts organisations’ strategies for engaging with critique have evolved in the digital age.

Design/methodology/approach

– This paper uses a content analysis of the online presence of 45 organisations. Based on the results, the organisations are classified into three different strategic approaches. The organisations’ publicly available financial data are analysed to explain differences in the choice of strategic approach, and specific cases are used to better understand their strategic execution.

Findings

– Organisations are engaging in three primary strategic responses: ignoring outside critique, presenting only positive reviews and ignoring or “spinning” negative reviews, and presenting all critique regardless of source or valence. The financial analysis suggests that the choice of strategic response varies across organisations of different sizes and approaches to advertising. Case analyses suggest that the strategy of presenting all critique has the potential to deepen audience engagement and value.

Originality/value

– Previous research on critical reviews has focused on traditional media and the importance of the professional critic. This paper is the first to examine strategies for coping with the complex, multiple-voiced nature of critique in the current online environment. The findings suggest questions for future research and provide initial guidelines for organisations in determining a strategic approach to responding to critique.
Routing algorithm with QoS constraints for real time multicast communications using particle swarm optimization and genetic meta-optimizer
Authors: CAMARGO YEISON JULIAN , Ramirez Leonardo Juan , Martinez Ana Karina
Published: April 2016

Purpose

The current work shows an approach to solve the QoS multicast routing problem by using Particle Swarm Optimization (PSO).

The problem of finding a route from a source node to multiple destination nodes (multicast) at a minimum cost is an NP-Complete problem (Steiner tree problem) and is even greater if Quality of Service -QoS- constraints are taken into account. Thus, approximation algorithms are necessary to
solve this problem. This work presents a routing algorithm with two QoS constraints (delay and delay variation) for solving the routing problem based on a modified version of particle swarm optimization.

Design/methodology/approach

This work involved the following methodology:
1. Literature Review
2. Routing algorithm design
3. Implementation of the designed routing algorithm by java programming.
4. Simulations and results.

Findings

In this work we compared our routing algorithm against the exhaustive search approach. The results showed that our algorithm improves the execution times in about 40% with different topologies.

Research limitations/implications

The algorithm was tested in three different topologies with 30, 40 and 50 nodes with and a dense graph topology.

Originality/value

Our algorithm implements a novel technique for fine tuning the parameters of the implemented bio-inspired model (Particles Swarm Optimization) by using a Genetic Meta-Optimizer. We also present a simple and multi implementation approach by using an encoding system that fits multiple bio-inspired models.
A computational and experimental study for the optimum reinforcement layout design of an RC frame
Authors: ÖZKAL Fatih Mehmet , UYSAL Habib
Published: April 2016

Purpose

Compared with conventional design methods, strut-and-tie modeling is a more suitable and even a superior method for the reinforcement layout design of structural members with uncommon geometrical shapes and/or regions essentially subject to shear effects. Because the determination of the optimum strut-and-tie model for each of the members is an important task, the implementation of a topology optimization method could be useful before the detailing stage.

Design/methodology/approach

Optimum reinforcement layout of a concrete frame was designed by an integrated approach, which consists of the topology optimization and strut-and-tie modeling methods. Subsequently, an experimental comparison of the new model with the conventional model was performed based on their structural behaviors.

Findings

Depending on the experimental results, it was concluded that the new integrated design method presents more successful results than does the conventional method for the design of reinforced concrete (RC) members.

Originality/value

The preference of the new method will facilitate the design process by eliminating the experience required of design engineers.
Design of energy efficient RAL system using evolutionary algorithms
Authors: Nilakantan Mukund J , Ponnambalam S G , N Jawahar
Published: April 2016

Purpose

Manufacturing industries these days gives importance to reduce the energy consumption due to the increase in energy prices and to create an environmental friendly industry. Robotic assembly lines (RALs) are used in an industry for assembling different types of products in an assembly line due to the flexibility it offers to the production system. Since different types of robots are available with different specialization and capabilities, there is a requirement of efficiently balancing the assembly line by allocating equal amount of tasks to the workstations and allocate the best fit robot to perform the allocated tasks. The goal of this paper is to maximize the line efficiency by minimizing the total energy consumption in a U-shaped robotic assembly line.

Design/methodology/approach

Particle swarm optimization (PSO) and Differential evolution (DE) are the two evolutionary algorithms used as the optimization tool to solve this problem. Performance of these proposed algorithm are tested on a set of randomly generated problems which are generated using the benchmark problems available in the open literature and the results are reported.

Findings

The proposed algorithm are found to be useful to reduce the total energy consumption on an assembly line which maximizes the line efficiency. It is found that DE algorithm could improve the line efficiency than PSO algorithm. Computational time taken by the two algorithm are also reported.

Originality/value

Till date, no research has been reported on optimizing the line efficiency by minimizing the total energy consumption in a U-shaped robotic assembly line systems. Particle swarm optimization (PSO) and Differential evolution (DE) are the two evolutionary algorithms used as the optimization tool to solve this problem.
Trust-region reflective optimisation to obtain soil visco-plastic properties
Authors: Le Thu Minh , Fatahi Behzad
Published: April 2016

Purpose

A non-linear creep function embedded in an elastic visco-plastic (EVP) model can simulate the decrease of creep compression rate with time. It overcomes the limitation of a linear logarithmic creep function, by which creep continuously increases to infinite value as time approaches infinity. However, the determination of the creep model parameters is a challenging task to apply the EVP model. Therefore, this paper presents a new numerical solution to determine the EVP model parameters applying trust-region reflective least square optimisation algorithm and the finite difference scheme to simulate stress-strain behaviour of soft soil.

Design/methodology/approach

In this paper, the developed method is verified against the field case study of Väsby test fill. A set of EVP model parameters is obtained by applying the developed method to the available laboratory consolidation results of Väsby clay. Then, the predictions of settlement and the excess pore water pressure at different depths are compared to the available field measurement.

Findings

The analysis results show the developed method is a reliable tool to evaluate the long-term performance of soft soils under embankments.

Practical implications

Practicing engineers can use the proposed optimisation algorithm to increase the accuracy of the soil visco-plastic model parameters by utilising all laboratory results of several loading stages during and after the dissipation of the excess pore water pressure.

Originality/value

A novel numerical solution to determine the viscoplastic model parameters applying trust-region reflective least square optimisation algorithm has been developed.
How women traverse an upward journey in Indian industry: multiple case studies
Authors: Chawla Sonam , Sharma Radha R.
Published: April 2016

Purpose

The purpose of this paper is to present multiple case studies of women in leadership roles in India with a view to identifying inhibitors, facilitators and the strategies adopted by them to mitigate the challenges in their odyssey to these positions. The paper contributes to the pivotal subject of under-representation of women in apex positions, which has garnered the attention of researchers in recent years grappling with the identification of the underlying causes. Thus, with a view to narrowing the gender gap in leadership positions, a greater understanding of this phenomenon is called for.

Design/methodology/approach

The paper adopts exploratory case study method using multiple case studies. Empirical data were gathered using in-depth semi-structured interviews and personality test (NEO FFI) from women in leadership positions. The qualitative data were analysed using thematic analysis.

Findings

The analysis of data has led to the identification of challenges faced by the women that were categorised as personal, professional, organisational and social issues. Further, six themes emerged as the strategies adopted by the women leaders to overcome the challenges. The paper also highlights the critical social, behavioural and organisational facilitators that played an important role in their leadership journey. The paper also includes context-specific findings of women leaders from Indian industry.

Practical implications

The paper would have relevance for researchers and practitioners in the field of gender diversity, leadership, organisational behaviour and human resource management. The findings of this paper can be leveraged by organisations to retain and manage female talent, which is a focal area in the present dynamic business environment, when a need for gender diversity is widely acknowledged by the top management in organisations. The exploratory case studies provide vistas for gender-based context-specific and cross-cultural research on the challenges faced by women executives in their leadership journey and the strategies adopted to mitigate these.

Originality/value

Though a great deal has been written about the barriers to women’s career advancement, less is known about the facilitators of women’s advancement. Also, women in the Asian context face unique challenges which present a major problem for multinational companies whose hopes for growth are pinned on emerging markets. The paper has identified new emergent themes, which have not been mentioned in the extant literature nationally or globally. The findings provide inputs to companies to adopt policies and practices to facilitate gender equality in leadership. The paper bridges the knowledge gap and makes conceptual contributions for future research.
Voter reaction to government incompetence and corruption related to the 1999 earthquakes in Turkey
Authors: Akarca Ali T. , Tansel Aysit
Published: April 2016

Purpose

– Two major earthquakes which struck Northwestern Turkey in 1999 exposed rampant corruption involving construction and zoning code violations. The government’s relief efforts were tainted by corruption as well, and exhibited a great deal of incompetence. How voters responded to these in the next election held in 2002 is investigated. The fact that different group of parties were responsible for the construction of the shoddy buildings, and for the corruption and mismanagement related to relief, provided us with a unique opportunity to determine whether and how the electorate punished the culprits for each of these. The purpose of this paper is to shed light also on the new party system which emerged in Turkey after 2002.

Design/methodology/approach

– Vote equations are estimated for the seven major political parties. These are fitted to cross-provincial data individually, using ordinary least squares and robust regression methods, and as a system, using seemingly unrelated regressions procedures. The same picture emerges from each of these methods.

Findings

– Not just those ruling at the time of the earthquakes, but also other parties which were in power when the substandard buildings, were built were held accountable by the electorate. Furthermore, the Turkish voters appear to have allocated the blame rationally, taking into consideration the division of labor in the central government, and the relative influences the parties had on local administrations. Reaction of the voters to government incompetence and corruption was one of the factors which resulted in the emergence of a new party system. In 2002, the AKP, established only a year before, captured almost all of the far-right Islamist, about half of the far-right nationalist, and more than half of the center-right votes in 2002.

Originality/value

– Corruption usually makes little difference in the fortunes of politicians. Some recent studies suggest that it takes more than just exposure of corruption to get the voters to react. Politicians pay a significant price only when the corruption touches all political parties across the board, is not accompanied by good governance, and competent non-corrupt alternatives are available. The results provide support for this assertion from the natural experiment that has taken place in Turkey.
Price differentiation and menu costs in credit card payments
Authors: Jorge Marcos Valli , Maldonado Wilfredo Leiva
Published: April 2016

Purpose

– The purpose of this paper is to model a credit card market where the retailers may charge differential prices depending on the instrument of payment used by the consumer. According to the research agenda proposed by Rochet and Wright (2010), the authors find conditions for the existence of differential prices equilibrium and analyze the effects of that price differentiation on the consumer’s welfare.

Design/methodology/approach

– This is done when the consumer has also the store credit as an alternative of payment. The equilibrium prices are computed assuming a Hotelling competition among retailers in both scenarios, when the cost of the store credit provided by the retailer is greater than that provided by the credit card and vice versa.

Findings

– From this, the authors prove that the average price under the price differentiation is lower than the single price under the no-surcharge rule; nevertheless, the retailer’s margins remain the same in both situations. Furthermore, some cross-subsidies are expunged when price differentiation is allowed. The authors also conclude that the consumers’ welfare is greater when the no-surcharge rule is abolished. Finally, if the retailers face menu costs whenever they differentiate prices, the authors provide sufficient conditions for differential prices remain as equilibrium.

Practical implications

– This is an important input for discussions among regulators and players of the credit card market.

Originality/value

– From the analysis the authors can conclude that price differentiation, according to the instrument of payment, is a welfare improving policy. The authors explicitly determine the average price in that setting and the differentiated prices even in presence of costs that arise from price differentiation. The obtained theoretical results can be used as an input for econometric modeling purposes.
How does education inequality respond to policy? A method and application to survey data from Albania and Nepal
Authors: Devkota Satis C. , Upadhyay Mukti P.
Published: April 2016

Purpose

– The purpose of this paper is to measure inequality in education and examine how socioeconomic factors affect education inequality in Albania and Nepal.

Design/methodology/approach

– Using large household survey data sets the authors calculate income-related inequality in education and decompose the inequality into factors that determine educational attainment. The decomposition procedure establishes the role played by two sets of factors: elasticities of education demand with respect to its determinants; and inequalities in those determinants. The paper then proposes a new mechanism to quantify the effects of policy simulations regarding income, urbanization, and distance to school on education inequality.

Findings

– Both the countries show significant inequality in education. Educational attainment in Albania and Nepal is determined by socioeconomic, demographic and geographic factors of which three are particularly significant in affecting inequality – income, urbanization and distance to school.

Research limitations/implications

– While schooling for most individuals is largely financed by public subsidy in the countries, attainment is also likely affected by the price of education services and cost of health care. Identification of those factors in the context of more comprehensive data will enable researchers in future to draw firmer conclusions.

Practical implications

– The proposed method can help to identify cost-effective and sustainable policies to reduce socioeconomic inequality in education in developing countries.

Social implications

– Reduction in education inequality can lead to higher income and better health which are instrumental in uplifting the poor in developing countries.

Originality/value

– This is the first paper to measure education inequality using a concentration index and to propose a new mechanism to show the effect of simulated policies on education inequality.
Mood and stock returns: evidence from Greece
Authors: Kourtidis Dimitrios , Šević Željko , Chatzoglou Prodromos
Published: April 2016

Purpose

– The purpose of this paper is to examine the effect of investors’ emotional state (mood) on their trading behaviour and performance.

Design/methodology/approach

– A sample from a representative survey of 328 Greek individual investors has been used to empirically test the validity of the proposed associations. An iterative data collection process was followed, where individual investors had to complete a questionnaire every time they were trading in the Athens Stock Exchange, for a period of ten months. Exploratory factor analysis was first used to analyse the data set, followed by cluster analysis (to identify investor profiles based on differences in their mood).

Findings

– Two clusters have been identified. The first cluster profile includes investors with high score of positive mood (thus, high energetic arousal and hedonic tone, low tense arousal and anger frustration), while the second profile consists of investors with negative mood (low energetic arousal and hedonic tone, high tense arousal and anger frustration). The comparison between the two profiles has shown that investors with positive mood achieve higher stock returns than investors with negative mood.

Originality/value

– To the best of the authors’ knowledge there is no other similar study.
How useful is the yield spread as a predictor of growth in Australia?
Authors: Chen George , Valadkhani Abbas , Grant Bligh
Published: April 2016

Purpose

– The purpose of this paper is to examine the usefulness of the yield spread for forecasting growth in the Australian economy since 1969.

Design/methodology/approach

– This paper applies time series analysis to evaluate the in-sample and out-of-sample forecasting power of the spread-growth nexus in Australia for the period spanning from 1969 to 2014.

Findings

– This paper concludes that the spread serves as a useful predictor of growth in output, private dwellings, private fixed capital formation, and inventories in Australia, both in-sample and out-of-sample. Its predictive content is not sensitive to the inclusion of monetary policy variables or the switch to the inflation-targeting regime by the Reserve Bank of Australia in the early 1990s.

Originality/value

– This paper provides significant evidence to policy makers and market participants on the usefulness of the spread in forecasting output growth for up to eight quarters ahead.
Strategic technology partnering capabilities
Authors: Kilubi Irene
Published: April 2016

Purpose

– Strategic technology partnering (STP) is considered to be significant for the access to novel technologies that are unknown to organisations. However, the performance heterogeneities within organisations can be explained by STP capabilities. Hence, the purpose of this paper is threefold: first, to provide a classificatory framework by categorising the various STP capabilities; second, to draw conclusions from the analysis of the empirical findings; and third, to guide further publications and identify future research needs.

Design/methodology/approach

– The present paper adopts a systematic literature review (SLR) methodology. In this research, the extant empirical research on STP capabilities will first be classified and integrated within a classificatory framework. Lastly, the review insights will provide methodological suggestions along with theoretical themes for future research that have not been yet explored.

Findings

– The study findings show that there is a strong need for a clear and unified terminology for the distinctive capabilities of STP and research has mainly highlighted certain common capabilities while other essential ones lack analysis. The SLR further reveals that most research has been quantitative in nature relying on secondary database research.

Originality/value

– This SLR provides a thorough overview of prior research on STP capabilities investigating 65 articles published in highly ranked peer-reviewed journals, spanning a 22-year period from 1992 to 2014. In sum, his review structures extant STP capabilities literature into a proposed classificatory framework referred to as “CLONT-framework” and highlights its critical importance in strategic management and innovation research from a theoretical, empirical, and practical point of view.