bluuebunny/crossref_metadata_2025 huggingface dataset:
Targeting Wnt Signaling To Overcome PARP Inhibitor Resistance
Authors: Yamamoto Tomomi M. , McMellen Alexandra , Watson Zachary L. , Aguilera Jennifer , Sikora Matthew J. , Ferguson Rebecca , Nurmemmedov Elmar , Thakar Tanay , Moldovan George-Lucian , Kim Hyunmin , Cittelly Diana M. , Wilson Heidi , Behbakht Kian , Bitler Benjamin G.
Published: July 2018

Epithelial ovarian cancer (EOC) has one of the highest deaths to incidence ratios. High grade serous ovarian carcinoma (HGSOC) is the most common and deadliest EOC histotype because of the lack of secondary therapeutic options following debulking surgery and platinum/taxane-based chemotherapies. For recurrent chemosensitive HGSOC, poly(ADP)-ribose polymerase inhibitors (PARPi; olaparib, rucaparib, or niraparib) represent an emerging treatment strategy. While PARPi are most effective in homologous recombination DNA repair-deficient (HRD) HGSOCs, more recent studies have observed a significant clinical benefit in non-HRD HGSOCs. However, all HGSOC patients are likely to acquire resistance to PARPi. Therefore, there is an urgent clinical need to better understand PARPi resistance, and to introduce novel combinatorial therapies to overcome PARPi resistance and extend HGSOC disease-free intervals. Utilizing a two BRCA2-mutated and one BRCA-wildtype HGSOC cell lines that are olaparib sensitive, we established resistant cells. Transcriptome analysis of the matched olaparib-sensitive versus resistant cells did not detect BRCA2 reversion mutations, but revealed activation of Wnt/TCF signaling pathway, as TCF transcriptional activity was significantly increased in PARPi-resistant cells. In parallel, forced activation of Wnt signaling in PARPi-sensitive cells via WNT3A stimulation reduced response to PARPi. In a recurrent-HGSOC PARPi insensitive patient-derived xenograft model there was an increase in a Wnt/TCF transcriptional target. PARPi resistant cells were sensitive to inhibition of Wnt signaling using the FDA-approved compound, pyrvinium pamoate, which has been shown to inhibit Wnt signaling. We observed that combining pyrvinium pamoate with olaparib resulted in a significant decrease in tumor burden and number of tumor nodules. This study demonstrates that Wnt signaling can mediate PARPi resistance in HGSOC and provides a clinical rationale for combining PARPi and Wnt inhibitors.
Proximal recolonization by self-renewing microglia reestablishes microglial homeostasis in the adult mouse brain
Authors: Zhan Lihong , Krabbe Grietje , Du Fei , Jones Ian , Reichert Meredith C. , Telpoukhovskaia Maria , Kodama Lay , Wang Chao , Cho Seo-hyun , Sayed Faten , Li Yaqiao , Le David , Zhou Yungui , Shen Yin , West Brian , Gan Li
Published: July 2018

Microglia are resident immune cells that play critical roles in maintaining normal physiology of the central nervous system. Remarkably, microglia have intrinsic capacity to replenish after being acutely ablated. However, the underlying mechanisms that drive such microglial restoration remain elusive. Here, we removed microglia via CSF1R inhibitor PLX5622 and characterized repopulation both spatially and temporally. We also investigated the cellular origin of repopulated microglia and report that microglia are replenished via self-renewal, with little contribution from non-microglial lineage progenitors, including nestin+ progenitors and the circulating myeloid population. Interestingly, spatial analyses with multi-color labeling reveal that newborn microglia recolonize the parenchyma by forming distinctive clusters that maintain stable territorial boundaries over time, indicating proximal expansion nature of adult microgliogenesis and stability of microglia tiling. Temporal transcriptome profiling from newborn microglia at different repopulation stages revealed that the adult newborn microglia gradually regain steady-state maturity from an immature state that is reminiscent of neonatal stage and follow a series of maturation programs that include NF-κB activation, interferon immune activation and apoptosis, etc. Importantly, we show that the restoration of microglial homeostatic density requires NF-κB signaling as well as apoptotic egress of excessive cells. In summary, our study reports key events that take place from microgliogenesis to homeostasis re-establishment.
Topological segregation of functional networks increases in developing brains
Authors: He Wei , Sowman Paul F. , Brock Jon , Etchell Andrew C. , Stam Cornelis J. , Hillebrand Arjan
Published: July 2018

A growing literature conceptualises human brain development from a network perspective, but it remains unknown how functional brain networks are refined during the preschool years. The extant literature diverges in its characterisation of functional network development, with little agreement between haemodynamic- and electrophysiology-based measures. In children aged from 4 to 12 years, as well as adults, age appropriate magnetoencephalography was used to estimate unbiased network topology, using minimum spanning tree (MST) constructed from phase synchrony between beamformer-reconstructed time-series. During childhood, network topology becomes increasingly segregated, while cortical regions decrease in centrality. We propose a heuristic MST model, in which a clear developmental trajectory for the emergence of complex brain networks is delineated. Our results resolve topological reorganisation of functional networks across temporal and special scales in youth and fill a gap in the literature regarding neurophysiological mechanisms of functional brain maturation during the preschool years.
Out of Africa by spontaneous migration waves
Authors: Bons Paul D. , Bauer Catherine C. , Bocherens Hervé , de Riese Tamara , Drucker Dorothée G. , Francken Michael , Menéndez Lumila , Uhl Alexandra , van Milligen Boudewijn P. , Wiβing Christoph
Published: July 2018

Hominin evolution is characterized by progressive regional differentiation, as well as migration waves, leading to anatomically modern humans that are assumed to have emerged in Africa and spread over the whole world. Why or whether Africa was the source region of modern humans and what caused their spread remains subject of ongoing debate. We present a spatially explicit, stochastic numerical model that includes ongoing mutations, demic diffusion, assortative mating and migration waves. Diffusion and assortative mating alone result in a structured population with relatively homogeneous regions bound by sharp clines. The addition of migration waves results in a power-law distribution of wave areas: for every large wave, many more small waves are expected to occur. This suggests that one or more out-of-Africa migrations would probably have been accompanied by numerous smaller migration waves across the world. The migration waves are considered “spontaneous”, as the current model excludes environmental or other factors. Large waves preferentially emanate from the central areas of large, compact inhabited areas. During the Pleistocene, Africa was the largest such area most of the time, making Africa the statistically most likely origin of anatomically modern humans, without a need to invoke additional environmental or ecological drivers.
The cap size and shape of Arabidopsis thaliana primary roots impact the root responses to an increase in medium strength
Authors: Roué J. , Chauvet H. , Brunel-Michac N. , Bizet F. , Moulia B. , Badel E. , Legué V.
Published: July 2018

During root progression in soil, root cap cells are the first to encounter obstacles. The root cap is known to sense environmental cues, making it a relevant candidate for a mechanosensing site. An original two-layer medium was developed in order to study root responses to growth medium strength and the importance of the root cap in the establishment of these responses. Root growth and trajectory of primary roots of Arabidopsis thaliana seedlings were investigated using in vivo image analysis. After contact with the harder layer, the root either penetrated it or underwent rapid curvature, enabling reorientation of the root primary growth. The role of the root cap in tip reorientation was investigated by analyzing the responses of Arabidopsis mutant roots with altered caps. The primary root of fez-2 mutant lines, which has fewer root cap cell layers than wild-type roots, showed impaired penetration ability. Conversely, smb-3 roots of mutant lines, which display a higher number of root cap cells, showed enhanced penetration abilities. This work highlights that alterations in root cap shape and size affect the root responses to medium strength.

Highlight

The analysis of the growth and orientation of Arabidopsis thaliana mutant roots affected in root cap size and shape showed that properly formed root cap is required to trigger the root responses to medium strength.

Abbreviations

COL

columella;

LRC

Lateral Root Cap;

SI

Sharpness Index;

SMB

SOMBRERO.
Step-wise evolution of temperature-mediated phenotypic plasticity in eyespot size across nymphalid butterflies
Authors: Bhardwaj Shivam , Jolander Lim Si-Hui , Wenk Markus R. , Oliver Jeffrey C. , Nijhout H. Frederik , Monteiro Antónia
Published: July 2018

There are two disparate views regarding phenotypic plasticity. One regards plasticity as a derived adaptation to help organisms survive in variable environments1, 2while the other views plasticity as the outcome of flexible, non-canalized, developmental processes, ancestrally present in most organisms, that helps them colonize or adapt to novel environments3–5e.g., a pre-adaptation. Both views of plasticity currently lack a rigorous, mechanistic examination of ancestral and derived states and direction of change2. Here we show that the origin of phenotypic plasticity in eyespot size in response to environmental temperature observed inBicyclus anynanabutterflies is a derived adaptation of this lineage. Eyespot size is regulated by temperature-mediated changes in levels of a steroid hormone, 20E, that affects proliferation of eyespot central cells expressing the 20E receptor (EcR)6, 7. By estimating the origin of the known physiological and molecular components of eyespot size plasticity in a comparative framework, we showed that 20E titer plasticity in response to temperature is a pre-adaptation shared by all butterfly species examined, whereas the origin of expression of EcR in eyespot centers, and the origin of eyespot sensitivity to the hormone-receptor complex are both derived traits found only in a subset of species with eyespots. The presence of all three molecular components required to produce a plastic response is only observed inB. anynana. This gradual, step-wise, physiological/molecular response to temperature is a likely adaptation to temperature variation experienced across wet and dry seasons in the habitat of this species. This work supports, thus, the first view of plasticity as a derived adaptation.
Comprehensive analysis of retinal development at single cell resolution identifies NFI factors as essential for mitotic exit and specification of late-born cells
Authors: Clark Brian S. , Stein-O’Brien Genevieve L. , Shiau Fion , Cannon Gabrielle H. , Davis Emily , Sherman Thomas , Rajaii Fatemeh , James-Esposito Rebecca E. , Gronostajski Richard M. , Fertig Elana J. , Goff Loyal A. , Blackshaw Seth
Published: July 2018

Precise temporal control of gene expression in neuronal progenitors is necessary for correct regulation of neurogenesis and cell fate specification. However, the extensive cellular heterogeneity of the developing CNS has posed a major obstacle to identifying the gene regulatory networks that control these processes. To address this, we used single cell RNA-sequencing to profile ten developmental stages encompassing the full course of retinal neurogenesis. This allowed us to comprehensively characterize changes in gene expression that occur during initiation of neurogenesis, changes in developmental competence, and specification and differentiation of each of the major retinal cell types. These data identify transitions in gene expression between early and late-stage retinal progenitors, as well as a classification of neurogenic progenitors. We identify here the NFI family of transcription factors (Nfia, Nfib, and Nfix) as genes with enriched expression within late RPCs, and show they are regulators of bipolar interneuron and Müller glia specification and the control of proliferative quiescence.
Memory sequencing reveals heritable single cell gene expression programs associated with distinct cellular behaviors
Authors: Shaffer Sydney M. , Emert Benjamin L. , Reyes-Hueros Raul , Coté Christopher , Harmange Guillaume , Sizemore Ann E. , Gupte Rohit , Torre Eduardo , Singh Abhyudai , Bassett Danielle S. , Raj Arjun
Published: July 2018

Non-genetic factors can cause individual cells to fluctuate substantially in gene expression levels over time. Yet it remains unclear whether these fluctuations can persist for much longer than the time of one cell division. Current methods for measuring gene expression in single cells mostly rely on single time point measurements, making the duration of gene expression fluctuations or cellular memory difficult to measure. Here, we report a method combining Luria and Delbrück’s fluctuation analysis with population-based RNA sequencing (MemorySeq) for identifying genes transcriptome-wide whose fluctuations persist for several cell divisions. MemorySeq revealed multiple gene modules that are expressed together in rare cells within otherwise homogeneous clonal populations. Further, we found that these rare cell subpopulations are associated with biologically distinct behaviors, such as the ability to proliferate in the face of anti-cancer therapeutics, in different cancer cell lines. The identification of non-genetic, multigenerational fluctuations has the potential to reveal new forms of biological memory at the level of single cells and suggests that non-genetic heritability of cellular state may be a quantitative property.
Migration and Differentiation of Osteoclast Precursors under Gradient Fluid Shear Stress
Authors: Gao Y , Li T. Y , Sun Q. , Ye C. Y , Guo M. M. , Chen Z. B. , Chen J. , Huo B.
Published: July 2018

The skeleton is able to adapt to mechanical loading through bone remodeling, i.e. bone resorption followed by bone formation. The osteoclasts close to microdamages are believed to initiate bone resorption, but whether local mechanical loading such as fluid flow regulates recruitment and differentiation of osteoclast precursors at the site of bone resorption has yet to be investigated. In the present study, finite element analysis first revealed that there exists low fluid shear stress (FSS) field inside microdamage. Basing on a custom-made device of cone-and-plate fluid chamber, finite element analysis and particle image velocimetry measurement were performed to verify the formation of gradient FSS flow field. Furthermore, the effects of gradient FSS on the migration, aggregation, and fusion of osteoclast precursors were observed. Results showed that osteoclast precursor RAW264.7 cells migrate along radial direction toward the region with lower FSS during exposure to gradient FSS stimulation for 40 min, obviously deviating from the direction of actual fluid flow indicated by fluorescent particles. When inhibiting calcium signaling pathway with gadolinium and thapsigargin, cell migration toward low-FSS region was significantly reduced. For other cell lines, MC3T3-E1, PDLF, rMSC and MDCK, gradient FSS stimulation did not lead to the low-FSS-inclined migration. After being cultured under gradient FSS stimulation for 6 days, the density of RAW264.7 cells and the ratio of TRAP-positive multinucleated osteoclasts in low-FSS region were significantly higher than those in high-FSS region. Therefore, osteoclast precursor cells may have special ability to sense FSS gradient and tend to actively migrate toward low-FSS region, which is regulated by calcium signaling pathway.
Prospects for enhancing leaf photosynthetic capacity by manipulating mesophyll cell morphology
Authors: Ren Tao , Weraduwage Sarathi M , Sharkey Thomas D.
Published: July 2018

Leaves are beautifully specialized organs designed to maximize the use of light and CO2 for photosynthesis. Engineering leaf anatomy therefore brings great potential to enhance photosynthetic capacity. Here we review the effect of the dominant leaf anatomical traits on leaf photosynthesis and confirm that a high chloroplast surface area exposed to intercellular airspace per unit leaf area (Sc) is critical for efficient photosynthesis. The possibility of improving Sc through appropriately increasing mesophyll cell density is further analyzed. The potential influences of modifying mesophyll cell morphology on CO2 diffusion, light distribution within the leaf, and other physiological processes are also discussed. Some potential target genes regulating leaf mesophyll cell proliferation and expansion are explored. Indeed, more comprehensive research is needed to understand how manipulating mesophyll cell morphology through editing the potential target genes impact leaf photosynthetic capacity and related physiological processes. This will pinpoint the targets for engineering leaf anatomy to maximize photosynthetic capacity.

Highlight

Cell morphology in leaves affects photosynthesis by controlling CO2 diffusion and light distribution. Recent work has uncovered genes that control cell size, shape, and number paving the way improved photosynthesis.
Dynamic recovery from depression enables rate encoding in inhibitory synapses
Authors: Huang Shiyong , Bridi Morgan S. , Kirkwood Alfredo
Published: July 2018

Fast-spiking parvalbumin positive interneurons (PV-INs) are essential for controlling network firing and the gain of the cortical response to sensory stimulation. Crucial for these functions, PV-INs can sustain high frequency firing with no accommodation. However, PV-INs also exhibit short-term depression (STD) during sustained activation, which is largely due to the depletion of synaptic resources (vesicles). In most synapses the rate of replenishment of depleted vesicles is constant, determining an inverse relationship between the STD level and the activation rate, which theoretically, severely limits rate coding capabilities. We examined STD of the PV-IN to pyramidal cell synapse in the mouse visual cortex, and found that in these synapses the recovery of depleted resources is not constant but increases linearly with the frequency of use. By combining modeling, dynamic clamp and optogenetics, we demonstrated that this dynamic regulation of recovery enables PV-INs to reduce pyramidal cell firing in a linear manner, which, theoretically, is crucial for controlling the gain of cortical visual responses.
Cryptic Promoter Activation Drives POU5F1 (OCT4) Expression in Renal Cell Carcinoma
Authors: Siebenthall Kyle T. , Miller Chris P. , Vierstra Jeff D. , Mathieu Julie , Tretiakova Maria , Reynolds Alex , Sandstrom Richard , Rynes Eric , Neph Shane J. , Haugen Eric , Johnson Audra , Nelson Jemma , Bates Daniel , Diegel Morgan , Dunn Douglass , Frerker Mark , Buckley Michael , Kaul Rajinder , Zheng Ying , Himmelfarb Jonathan , Ruohola-Baker Hannele , Akilesh Shreeram
Published: July 2018

Transcriptional dysregulation drives cancer formation but the underlying mechanisms are still poorly understood. As a model system, we used renal cell carcinoma (RCC), the most common malignant kidney tumor which canonically activates the hypoxia-inducible transcription factor (HIF) pathway. We performed genome-wide chromatin accessibility and transcriptome profiling on paired tumor/normal samples and found that numerous transcription factors with a RCC-selective expression pattern also demonstrated evidence of HIF binding in the vicinity of their gene body. Some of these transcription factors influenced the tumor’s regulatory landscape, notably the stem cell transcription factor POU5F1 (OCT4). Unexpectedly, we discovered a HIF-pathway-responsive cryptic promoter embedded within a human-specific retroviral repeat element that drives POU5F1 expression in RCC via a novel transcript. Elevat POU5F1 expression levels were correlated with advanced tumor stage and poorer overall survival in RCC patients. Thus, integrated transcriptomic and epigenomic analysis of even a small number of primary patient samples revealed remarkably convergent shared regulatory landscapes and a novel mechanism for dysregulated expression of POU5F1 in RCC.
Shortened lifespan and other age-related defects in bang sensitive mutants ofDrosophila melanogaster
Authors: Reynolds Elaine R.
Published: July 2018

Mitochondrial diseases are complex disorders that exhibit their primary effects in energetically active tissues. Damage generated by mitochondria is also thought to be a key component of aging and age-related disease. An important model for mitochondrial dysfunction is the bang sensitive (bs) mutants inDrosophila melanogaster. Although these mutants all show a striking seizure phenotype, several bs mutants have gene products that are involved with mitochondrial function, while others affect excitability another way. All of the bs mutants (parabss, eas, jus, ses B, tkoare examined here) paralyze and seize upon challenge with a sensory stimulus, most notably mechanical stimulation. These and other excitability mutants have been linked to neurodegeneration with age. In addition to these phenotypes, we have found age-related defects for several of the bs strains. The mutantseas, ses B, andtkodisplay shortened lifespan, an increased mean recovery time from seizure with age, and decreased climbing ability over lifespan as compared to isogenic CS orw1118lines.. Other mutants show a subset of these defects. The age-related phenotypes can be rescued by feeding melatonin, an antioxidant, in all the mutants exceptses B. The age-related defects do not appear to be correlated with the seizure phenotype. Inducing seizures on a daily basis did not exacerbate the phenotypes and treatment with antiepileptic drugs did not increase lifespan. The results suggest that the excitability phenotypes and the age-related phenotypes may be somewhat independent and that these phenotypes mutants may arise from impacts on different pathways.
Rapid sample delivery for megahertz serial crystallography at X-ray FELs
Authors: Wiedorn Max O. , Awel Salah , Morgan Andrew J. , Ayyer Kartik , Gevorkov Yaroslav , Fleckenstein Holger , Roth Nils , Adriano Luigi , Bean Richard , Beyerlein Kenneth R. , Chen Joe , Coe Jesse , Cruz-Mazo Francisco , Ekeberg Tomas , Graceffa Rita , Heymann Michael , Horke Daniel A. , Knoška Juraj , Mariani Valerio , Nazari Reza , Oberthür Dominik , Samanta Amit K. , Sierra Raymond G. , Stan Claudiu A. , Yefanov Oleksandr , Rompotis Dimitrios , Correa Jonathan , Erk Benjamin , Treusch Rolf , Schulz Joachim , Hogue Brenda G. , Gañán-Calvo Alfonso M. , Fromme Petra , Küpper Jochen , Rode Andrei V. , Bajt Saša , Kirian Richard A. , Chapman Henry N.
Published: July 2018

Liquid microjets are a common means of delivering protein crystals to the focus of X-ray free-electron lasers (FELs) for serial femtosecond crystallography measurements. The high X-ray intensity in the focus initiates an explosion of the microjet and sample. With the advent of X-ray FELs with megahertz rates, the typical velocities of these jets must be increased significantly in order to replenish the damaged material in time for the subsequent measurement with the next X-ray pulse. This work reports the results of a megahertz serial diffraction experiment at the FLASH FEL facility using 4.3 nm radiation. The operation of gas-dynamic nozzles that produce liquid microjets with velocities greater than 80 m s−1 was demonstrated. Furthermore, this article provides optical images of X-ray-induced explosions together with Bragg diffraction from protein microcrystals exposed to trains of X-ray pulses repeating at rates of up to 4.5 MHz. The results indicate the feasibility for megahertz serial crystallography measurements with hard X-rays and give guidance for the design of such experiments.
Synthesis, crystal structure and topological analysis of a three-dimensional polymeric network based on zinc(II), potassium and 5-sulfobenzene-1,3-dicarboxylate (SIP)
Authors: Silva Flávia H. , Franco Chris H. J. , Corrêa Charlane C. , Diniz Renata
Published: July 2018

Aromatic polycarboxylate linkers provide structural rigidity and strong interactions among the metal centre and the carboxylate O atoms. A new three-dimensional coordination polymer namely, catena-poly[potassium [tetraaqua(μ-5-sulfobenzene-1,3-dicarboxylato)zinc(II)]], {K[Zn(C8H3O7S)(H2O)4]}
n
or {K[Zn(SIP)(H2O)4]}
n
, where SIP is 5-sulfobenzene-1,3-dicarboxylate or 5-sulfoisophthalate, was obtained and characterized by elemental analysis and IR vibrational spectroscopy, and the single-crystal structure was determined by X-ray diffraction analysis. The compound crystallizes in the monoclinic space group P21/n with Z = 4. Topological analysis revealed that K—O interactions form a two-dimensional network, which is uninodal 4-connected and can be described with a point symbol (44.62), and this plane network is classified as sql/Shubnikov. The layers are connected by Zn2+ ions coordinated to the SIP linker, forming a three-dimensional network. This net is a trinodal (3,5,6)-connected system with point symbol (3.44.52.62.73.83).(3.44.52.62.7).(3.72).
The impact of board characteristics and ownership identity on agency costs and firm performance: UK evidence
Authors: Allam Bahaaeldin Samir
Published: July 2018

Purpose

This paper aims to provide a twofold empirical comparison: first, a comparison between the impact of corporate governance mechanisms on agency costs proxies and firm performance measures, and second, this comparison was used before and after the 2008 financial crisis, capturing two different economic states.

Design/methodology/approach

Panel regression methods were applied to two data sets of non-financial firms incorporated in the FTSE ALL-Share index over the period 2005-2011.

Findings

The results provide evidence that not all mechanisms lead to lower agency conflicts and/or higher firm performance. Ownership identity has a significant impact and the role of the governance mechanisms changes with the changes in the economic conditions surrounding the firm.

Research limitations/implications

The results lend support to the notion that forcing a certain code of practice on firms to follow could compel them to move away from conflict reduction governance structures.

Originality/value

To the best of the authors’ knowledge, this is the first paper to provide a comparison of empirical evidence for the impact of board characteristics and ownership identity on agency costs and firm performance by using a comprehensive set of corporate governance mechanisms. This comparison challenges the prior studies that use performance as an indirect proxy for lower agency costs. Additionally, it compares the impact of the governance mechanisms during two different economic conditions.
Influence of magnetic concentrator on Hall effect based current sensor
Authors: Yatchev Ivan , Sen Mehmet , Balabozov Iosko , Kostov Ivan
Published: July 2018

Purpose

The purpose of the paper is to clarify the influence of introducing magnetic concentrators on the performance of Hall effect based current sensors and to obtain dependencies of the sensor characteristics on the conductor position.

Design/methodology/approach

The finite element method and Comsol software are used for analysis of the three-dimensional magnetic field of the constructions of Hall effect based current sensor with different types of magnetic concentrators – closed-core (of rectangular and toroidal type) and open-core of toroidal type – with additional larger air gap. The Hall plate is also included in the model with its real dimensions and the magnetic flux density is obtained by integrating over its volume.

Findings

It has been found that there is dependence of the output signal (proportional to the magnetic flux density) of Hall effect based current sensor with both closed- and open-core magnetic concentrators on the position of the current carrying conductor. Distribution of the magnetic flux density and dependencies of its value in the Hall plate on the conductor position and on the additional air gap have been obtained. Optimization is carried out with respect to the additional air gap and cross-section dimensions of the concentrator.

Originality/value

Estimation of the influence of the introducing magnetic concentrators is made with respect to relationships between the output signal and conductor position for different constructions of the magnetic core of the concentrators.
Visual-aided ontology-based ranking on multidimensional data: a case study in academia
Authors: Triperina Evangelia , Bardis Georgios , Sgouropoulou Cleo , Xydas Ioannis , Terraz Olivier , Miaoulis Georgios
Published: July 2018

Purpose

The purpose of this paper is to introduce a novel framework for visual-aided ontology-based multidimensional ranking and to demonstrate a case study in the academic domain.

Design/methodology/approach

The paper presents a method for adapting semantic web technologies on multiple criteria decision-making algorithms to endow to them dynamic characteristics. It also showcases the enhancement of the decision-making process by visual analytics.

Findings

The semantic enhanced ranking method enables the reproducibility and transparency of ranking results, while the visual representation of this information further benefits decision makers into making well-informed and insightful deductions about the problem.

Research limitations/implications

This approach is suitable for application domains that are ranked on the basis of multiple criteria.

Originality/value

The discussed approach provides a dynamic ranking methodology, instead of focusing only on one application field, or one multiple criteria decision-making method. It proposes a framework that allows integration of multidimensional, domain-specific information and produces complex ranking results in both textual and visual form.
Sustainability in the professional accounting and finance curriculum: an exploration
Authors: Mburayi Langton , Wall Tony
Published: July 2018

Purpose

Whereas the integration of sustainability into business schools has received increasing attention in recent years, the debate continues to be generic rather than recognising the peculiarities of the more quantitative sub disciplines such as accounting and finance which may of course be intimately linked to professional standards. The purpose of this paper, therefore, is to examine the extent to which sustainability is integrated into accounting and finance curricula in business schools, how, and to understand some of the challenges of doing so.

Design/methodology/approach

This paper presents the findings from a systematic form of literature review which draws on the previous literature about how sustainability is embedded into business school curricula and the challenges in doing so. A particular focus is placed on how the ways in which sustainability is integrated into accounting and finance curricula in business schools.

Findings

The paper demonstrates that accounting and finance lags behind other management disciplines in embedding sustainability and that institutional commitment is oftentimes a strong imperative for effective integration of sustainability.

Practical implications

This paper is a call to practitioners and researchers alike to explore new ways of integrating sustainability in the accounting and finance curricula, including working across boundaries to provide learning opportunities for future accountants, financial managers and generalist managers.

Originality/value

The paper offers an original analysis and synthesis of the literature in the context of the accounting and finance curricula in business schools, and proposed a conceptual framework to further develop sustainability education in the context of business schools.
Teaching lean manufacturing at a postgraduate level
Authors: Tortorella Guilherme , Cauchick-Miguel Paulo A.
Published: July 2018

Purpose

This study aims at integrating two teaching approaches to enhance Lean manufacturing (LM) learning at a graduate course level and verify its effectiveness through comparing students’ performance and learning preferences.

Design/methodology/approach

The proposed methodology incorporates problem-based learning (PBL) approach based on real problems of companies undergoing a lean implementation into traditional teaching methods. The methodology was applied with graduate students from a Brazilian public university, whose learning preferences were subsequently identified. The verification of effectiveness is undertaken through a comparative analysis of students’ performance after each course.

Findings

The findings indicate that PBL may be an effective complementary method for LM learning, especially because it exposes students to actual problems when implementing LM. The proposal may improve problem-solving ability and provide a more fertile environment to promote better learning experience. The results are also positively related to the current body of the literature. Finally, because of different students’ learning preferences, PBL alone may not fulfill all students’ cognitive requirements, and hence, traditional teaching methods should not be eradicated from the LM learning process.

Originality/value

Because of an increasingly worldwide competition regarding business performance, LM has been an emerging and relevant subject among engineering and management postgraduate courses. Nevertheless, the practical character inherent to the understanding of LM may undermine learning and development of students. Therefore, studies that verify the effectiveness of the teaching approach may contribute to better prepare students for such demanding context.
Mentoring novice school principals in Chile: what do mentors learn?
Authors: Aravena Felipe
Published: July 2018

Purpose

The purpose of this paper is to explore the mentors’ knowledge gained of eight Chilean mentors during their first experience working within a formal mentoring program supporting novice school principals.

Design/methodology/approach

This study uses a qualitative approach. Research design, data collection and data analysis comprise an interpretative approach to aid the understanding of the learnings and personal processes involved in the mentoring experiences of mentors. For that the authors have coded 280 reflection sheets from the whole process of mentoring.

Findings

Mentors learn how the system works, how the school context offers opportunities and limitations for novice school principals, how they themselves perform their role and what professional strategies are effective for supporting new principals. In practical terms, mentors learn the relevance of being a good listener, critical friend, guide, supporter, respondent and source of knowledge.

Practical implications

Mentoring is an important professional activity that can promote the retention of principals and improve their organization and professional socialization within schools.

Originality/value

This is the first study presenting a formal experience in mentoring in Latin America.
An investigation of healthcare supply chain management and patient responsiveness
Authors: Polater Abdussamet , Demirdogen Osman
Published: July 2018

Purpose

This study aims to focus on the impact of supply chain (SC) integration, demand forecasting and supplier performance on patient responsiveness at public hospitals through the mediating role of SC flexibility.

Design/methodology/approach

To measure the above stated correlation, a Likert scale with five points and 23 items was used and structural equation modeling was applied. The scale was applied to public hospitals. Statistical software programs (SPSS 18 and LISREL 8.8) were used to analyze the data. The analysis of reported statistics is based on a sample of 129 logistics and SC specialists at public hospitals in the cities representing different regions of Turkey.

Findings

The research hypotheses are supported as a result of the analysis. The research reveals that SC flexibility has a mediation effect between SC integration, demand forecasting, supplier performance and patient responsiveness.

Practical implications

The increasing number of population, geopolitical position, migration waves, man-made and natural disasters lead Turkish health-care industry to have effective SC plans to satisfy the patients’ needs successfully and reduce the effects of these fatal events. In this sense, SC flexibility is an important factor for health-care industry in responding changing patient demands. At this juncture, the main point is to bring required resources together in the right place and at the right time. Otherwise, health-care institutions cannot serve the affected people because of the non-availability of supply. To achieve it, public health-care institutions should give more importance to the SC principles.

Originality/value

Success in SC flexibility in health care can directly affect patient welfare. Thus, focusing on the patient responsiveness is an important aim of the health-care industry. However, it was determined that less attention has been given to understanding patient satisfaction as a result of SC operations. The results indicate that patient responsiveness improvement should be included into strategic plans, and SC efforts should be used as a means of satisfying patient needs quickly. To the best of our knowledge, this is the first study investigating the mentioned relationships at public hospitals. Findings of this paper will have a significant contribution for researchers and health-care professionals in understanding the impact of SC to patient responsiveness.
Demographic characteristics of the board of directors’ structure and tax avoidance
Authors: Hoseini Mohammadreza , Safari Gerayli Mehdi , Valiyan Hasan
Published: July 2018

Purpose

The structure of corporate governance, as one of the important elements to be considered based on the different characteristics than other companies, such as women, expertise, tenure and management is different. But two measures for the presence of women in the board of directors and the size of director’s board are considered as corporate content characteristics that can affect corporate tax strategies in avoiding tax or taxes timely pay off. The purpose of this paper is to understand the demographic characteristics of the board of directors structure on the board and tax avoidance in Tehran Stock Exchange (TSE).

Design/methodology/approach

Sample includes the 505 firm-year observations from companies listed on the TSE during the years 2012–2016 and research hypothesis was tested using multivariate regression model based on panel data.

Findings

The results indicate that female presence on the board of directors reduces the corporate tax avoidance. Additionally, firms with a larger size of board of directors are associated with more tax avoidance.

Originality/value

The current study is almost the first study which has been conducted in Iran, so the findings of the study not only extend the extant theoretical literature concerning the tax avoidance in developing countries including emerging capital market of Iran, but also help investors, capital market regulators and accounting standard setters to make informed decisions.
An efficient robot payload identification method for industrial application
Authors: Dong Yunfei , Ren Tianyu , Chen Ken , Wu Dan
Published: July 2018

Purpose

This paper aims to improve the accuracy of robot payload identification and decrease the complexity in its industrial application by developing a new method based on the actuator current.

Design/methodology/approach

Instead of previous general robot dynamic modeling of the actuators, links, together with payload inertial parameters, the paper discovers that the difference of the actuator torque between the robot moving along the same trajectory with and without carrying payload can be described as a function of the payload inertial parameters directly. Then a direct dynamic identification model of payload is built, a set of specialized novel exciting trajectories are designed for accurate identification and the least square method is applied for the estimation of the load parameters.

Findings

The experiments confirm the effectiveness of the proposed method in robot payload identification. The identification accuracy is greatly improved compared with that of existing methods based on the actuator current and is close to the accuracy of the methods that direct use the wrist-mounted force-torque sensor.

Practical implications

As the provided experiments indicate, the proposed method expands the application range and greatly improves the accuracy, hence making payload identification fully operational in the industrial application.

Originality/value

The novelty of such an identification method is that it does not require the rotor inertias and inertial parameters of links as a prior knowledge, and the specially designed trajectories provide completed decoupling of the load parameters.
Is the accounting quality after the mandatory adoption of IFRS a random walk? Evidence from Europe
Authors: Morais Ana Isabel , Fialho Ana , Dionísio Andreia
Published: July 2018

Purpose

The purpose of this paper is to provide empirical evidence regarding the classification of European countries based on accounting quality metrics. The authors investigate whether the grouping of countries based on accounting quality levels differs from other classifications based on accounting practices or country-specific factors identified in previous studies.

Design/methodology/approach

The authors run panel data regressions for 2.078 European listed companies using value relevance and earnings smoothing metrics. The authors also apply cluster analysis to classify the countries.

Findings

The results suggest that the adoption of a common set of International Financial Reporting Standards (IFRS) did not lead to a similar level of accounting quality of financial information. The authors identified three clusters of countries that are not coincident with previous classifications.

Research limitations/implications

The results show that the adoption of different accounting practices allowed in IFRS does not necessarily influence accounting quality.

Practical implications

The results suggest that the way regulators decided to incorporate IFRS into national accounting systems is one issue that may be relevant in explaining the three clusters.

Originality/value

The paper provides empirical evidence that supports two theoretical assertions. The first is that a classification depends entirely on the characteristics used to represent the countries being classified. The second is that the adoption of a single set of accounting standards does not determine similar accounting practices and does not lead to similar levels of accounting quality.
Budget emphasis in small and medium-sized enterprises: evidence from Denmark
Authors: Sandalgaard Niels , Nielsen Christian
Published: July 2018

Purpose

The purpose of this paper is to investigate the use of budget targets for performance evaluation in small- and medium-sized enterprises (SMEs) from a contingency perspective.

Design/methodology/approach

This paper is based on a survey conducted among small- and medium-sized Danish production companies. It takes a contingency approach and applies structural equation modeling to analyze the data.

Findings

The authors find that budget emphasis is related to size, decentralization and interdependence. Furthermore, the authors hypothesize and find that the degree of budget emphasis is positively related to performance.

Research limitations/implications

The usual limitations associated with survey-based research should be considered before drawing conclusions from the findings. In that regard, replications of the study could be useful.

Practical implications

The practical implication of this paper is that emphasis on the budget target in performance evaluation is of relevance for small- and medium-sized production companies.

Originality/value

This paper contributes by providing insights into management accounting in SMEs. More specifically, this paper contributes to the debate in the SME literature regarding the value of planning and budgeting in SMEs as the paper focuses on the use of budgets for performance evaluation.
Investor reactions to restatements conditional on disclosure of internal control weaknesses
Authors: Li Yiwen , Park You-il , Wynn Jinyoung
Published: July 2018

Purpose

The purpose of this paper is to investigate investor reactions to financial restatements conditional on disclosures of internal control weaknesses under Section 404 of the Sarbanes-Oxley Act.

Design/methodology/approach

The research uses cumulative abnormal stock returns (CARs) as a proxy for investor reactions. Restatements and internal control reports are available on audit analytics. Multivariate regression analyses were used for testing.

Findings

Using a sample of restating firms whose original misstatements are linked to underlying internal control weaknesses, the research finds that cumulative abnormal returns for firms disclosing internal control weaknesses in a timely manner is negative in a three-day window around the restatement announcements. The finding indicates that restatements with early disclosure of internal control weaknesses provide more persuasive evidence of the ineffectiveness of a firm’s internal control over financial reporting, rather than early disclosure lowering the information asymmetry between a firm and investors.

Research limitations/implications

This study employs CARs to examine the market reaction to restatements conditional on disclosure of internal control weaknesses.

Practical implications

Further study on reactions by creditors who have access to private information on firms could extend the implications of the finding.

Originality/value

The study contributes to the existing research by documenting that early disclosure of material weaknesses in internal control affects investors’ reactions to financial restatements.
Customers becoming creators: how firms leverage technology and consumers for new value
Authors: Dal Zotto Pierre , Colombero Sylvain , Pigni Federico , Haggège Meyer
Published: July 2018

Purpose

The rapid development of information and communication technologies (ICTs) has facilitated consumers’ involvement in firms’ value creation processes through increasingly near real-time information exchanges. This strategic opportunity configures new forms of ICT-enabled collaboration between firms and consumers. Firms can now immediately react to consumers’ requests/complaints, having gained real-time visibility of consumers’ actions and behaviors. Despite the increasing deployment of ICT-enabled value co-creation projects, managers still poorly apprehend them as high-potential strategic initiatives.

Design/methodology/approach

This paper investigates this gap through a multiple qualitative case study based on 17 organizations that successfully implement ICT-based value co-creation initiatives, including Lego, Netflix and Blablacar.

Findings

This study identifies two dimensions of the ICTs’ value co-creation process, namely, the firms’ involvement and customers’ role, in this co-creation process. Through these dimensions, four ICT-based co-creation initiatives are observed and defined: community, customers’ contributions create the firms’ value proposition (FVP); customization, customers’ service consumption personalize FVP; reputation, customers’ contributions about the offered services completes the FVP; and sense, an algorithmic approach, designed to focus on learning from customers’ consumption tailors FVP.

Originality/value

This study advances a framework supporting managerial decision-making concerning the aptitude of co-creation initiatives to meet organizational goals. Managers may gain insight from its use especially in assessing emerging opportunities to engage consumers in the value creation process.