bluuebunny/crossref_metadata_2025 huggingface dataset:
FANCD2 tunes the UPR preventing mitochondrial stress-­induced common fragile site instability
Authors: Fernandes Philippe , Miotto Benoit , Saint-Ruf Claude , Nähse Viola , Ravera Silvia , Cappelli Enrico , Naim Valeria
Published: October 2019

Common fragile sites (CFSs) are genomic regions frequently involved in cancer-associated rearrangements. Most CFSs lie within large genes, and their instability relies on transcription- and replication-dependent mechanisms. Here, we uncover a role for the UBL5-dependent branch of the unfolded protein response pathway (UPR) in the maintenance of CFS stability. We show that genetic or pharmacological UPR activation induces CFS gene expression and concomitant relocalization of FANCD2, a master regulator of CFS stability, to CFSs. Furthermore, a genomic analysis of FANCD2 binding sites identified an enrichment for mitochondrial UPR transcriptional response elements in FANCD2 bound regions. We demonstrated that depletion of FANCD2 increases CFS gene transcription and their instability while also inducing mitochondrial dysfunction and triggering the activation of the UPR pathway. Depletion of UBL5, a mediator of the UPR, but not ATF4, reduces CFS gene expression and breakage in FANCD2-depleted cells. We thus demonstrate that FANCD2 recruitment and function at CFSs depends on transcription and UPR signaling, and in absence of transcription or UBL5, FANCD2 is dispensable for CFS stability. We propose that FANCD2 coordinates nuclear and mitochondrial activities by tuning the UPR to prevent genome instability.
Characterization of Arabidopsis thaliana promoter bidirectionality and antisense RNAs by depletion of nuclear RNA decay enzymes
Authors: Thieffry Axel , Bornholdt Jette , Ivanov Maxim , Brodersen Peter , Sandelin Albin
Published: October 2019

In animals, transcription by RNA polymerase II initiates bidirectionally from gene promoters to produce pre-mRNAs on the forward strand and promoter upstream transcripts (PROMPTs) on the reverse strand. PROMPTs are rapidly degraded by the nuclear exosome. Similarly, active enhancer regions in animals initiate transcription of exosome-sensitive enhancer RNAs (eRNAs). Previous studies based on nascent RNA approaches concluded that Arabidopsis thaliana does not produce PROMPTs. Here, we used steady-state RNA sequencing methods in mutants defective in nuclear RNA decay, including by the exosome, to reassess the existence of PROMPTs and eRNAs in A. thaliana. While PROMPTs are overall rare in A. thaliana, about 100 clear cases of exosome-sensitive PROMPTs and 113 loci producing eRNA-like transcripts were identified. In addition, we found ∼200 transcription start sites within 3’-UTR-encoding regions that produce unspliced exosome-sensitive antisense RNAs covering much of the cognate pre-mRNA. A typical representative of this class of RNAs is the previously characterized non-coding RNA controlling the expression of the key seed dormancy regulator, DELAY OF GERMINATION1. Exosome-sensitive antisense RNAs are overrepresented in transcription factor genes, suggesting a potential for widespread control of gene expression. Lastly, we assess the use of alternative promoters in A. thaliana and compare the accuracy of existing TSS annotations.
Deep brain stimulation modulates directional frontolimbic connectivity in obsessive‐compulsive disorder
Authors: Fridgeirsson Egill Axfjord , Figee Martijn , Luigjes Judy , van den Munckhof Pepijn , Schuurman P.Richard , Wingen Guido van , Denys Damiaan
Published: October 2019

Deep brain stimulation (DBS) is effective for patients with treatment‐refractory obsessive‐compulsive disorder. DBS of the ventral anterior limb of the internal capsule (vALIC) rapidly improves mood and anxiety with optimal stimulation parameters. To understand these rapid effects of vALIC‐DBS, we studied functional interactions within the affective amygdala circuit. We compared resting state functional magnetic resonance imaging data during chronic stimulation versus one week of stimulation discontinuation in patients, and obtained two resting state scans from matched healthy volunteers to account for test‐retest effects. Imaging data were analyzed using functional connectivity analysis and dynamic causal modelling. Improvement in mood and anxiety following DBS was associated with reduced amygdala‐insula functional connectivity. Directional connectivity analysis revealed that DBS increased the impact of the ventromedial prefrontal cortex on the amygdala, and decreased the impact of the amygdala on the insula. These results highlight the importance of the amygdala circuit in the pathophysiology of OCD, and suggest a neural systems model through which negative mood and anxiety are modulated by vALIC‐DBS for OCD and possibly other psychiatric disorders.

One Sentence Summary

Deep brain stimulation improves mood and anxiety in obsessive‐compulsive disorder by altering connectivity between the amygdala, insula and prefrontal cortex.
Protein Interactome of the Cancerous Inhibitor of Protein Phosphatase 2A (CIP2A) in Th17 Cells
Authors: Khan Mohd Moin , Välikangas Tommi , Khan Meraj Hasan , Moulder Robert , Ullah Ubaid , Bhosale Santosh Dilip , Komsi Elina , Butt Umar , Qiao Xi , Westermarck Jukka , Elo Laura L , Lahesmaa Riitta
Published: October 2019

Cancerous inhibitor of protein phosphatase 2A (CIP2A) is involved in immune response, cancer progression, and in Alzheimer’s disease. However, an understanding of the mechanistic basis of its function in this wide spectrum of physiological and pathological processes is limited due to its poorly characterized interaction networks. Here we present the first systematic characterization of the CIP2A interactome by affinity-purification mass spectrometry combined with validation by selected reaction monitoring targeted mass spectrometry (SRM-MS) analysis in Th17 cells. In addition to the known regulatory subunit of protein phosphatase PP2A, the catalytic subunit of protein PP2A was found to be interacting with CIP2A. Furthermore, the regulatory (PPP1R18, and PPP1R12A) and catalytic (PPP1CA) subunits of phosphatase PP1 were identified among the top novel CIP2A interactors. Evaluation of the ontologies associated with the proteins in this interactome revealed that they were linked with RNA metabolic processing and splicing, protein traffic, cytoskeleton regulation and ubiquitin-mediated protein degradation processes. Taken together, this network of protein-protein interactions will be important for understanding and further exploring the biological processes and mechanisms regulated by CIP2A both in physiological and pathological conditions.

Highlights

▪ The first characterisation of the CIP2A interactome in Th17 cells.

▪ Key interactions were validated by targeted SRM-MS proteomics, western blot and confocal microscopy.

▪ Pathway analysis of the interactome revealed interrelationships with proteins across a broad range of processes, in particular associated with mRNA processing.
ILF3 contributes to the establishment of the antiviral type I interferon program
Authors: Watson Samir F. , Bellora Nicolas , Macias Sara
Published: October 2019

Upon detection of viral infections, cells activate the expression of type I interferons (IFNs) and pro-inflammatory cytokines to control viral dissemination. As part of their antiviral response, cells also trigger the translational shutoff response which prevents translation of viral mRNAs and cellular mRNAs in a non-selective manner. Intriguingly, mRNAs encoding for antiviral factors bypass this translational shutoff, suggesting the presence of additional regulatory mechanisms enabling expression of the self-defence genes. Here, we identified the dsRNA binding protein ILF3 as an essential host factor required for efficient translation of the central antiviral cytokine,IFNB1, and a subset of interferon-stimulated genes. By combining polysome profiling and next-generation sequencing, ILF3 was also found to be necessary to establish the dsRNA-induced transcriptional and translational programs. We propose a central role for the host factor ILF3 in enhancing expression of the antiviral defence mRNAs in cellular conditions where cap-dependent translation is compromised.
Precise coupling of the thalamic head-direction system to hippocampal ripples
Authors: Viejo Guillaume , Peyrache Adrien
Published: October 2019

The anterior thalamus is a key relay of neuronal signals within the limbic system. During sleep, the occurrence of hippocampal sharp wave-ripples (SWRs), believed to mediate consolidation of explicit memories, is modulated by thalamocortical network activity, yet how information is routed around SWRs and how this communication depends on neuronal dynamics remains unclear. Here, by simultaneously recording ensembles of neurons in the anterior thalamus and local field potentials in the CA1 area of the hippocampus, we show that the head-direction (HD) cells of the anterodorsal nucleus are set in stable directions immediately before SWRs. This response contrasts with other thalamic cells that exhibit diverse couplings to the hippocampus related to their intrinsic dynamics but independent of their anatomical location. Thus, our data suggest a specific and homogeneous contribution of the HD signal to hippocampal activity and a diverse and cell-specific coupling of non-HD neurons.
Evolution of the acoustic startle response of Mexican cavefish
Authors: Paz Alexandra , McDole Brittnee , Kowalko Johanna E. , Duboue Erik R. , Keene Alex C.
Published: October 2019

The ability to detect threatening sensory stimuli and initiate an escape response is essential for survival and under stringent evolutionary pressure. In diverse fish species, acoustic stimuli activate Mauthner neurons, which initiate a stereotypical C-start escape response. This reflexive behavior is highly conserved across aquatic species and provides a model for investigating the neural mechanism underlying the evolution of escape behavior. Here, we define evolved differences in the C-start response between populations of the Mexican cavefish,Astyanax mexicanus. Cave populations ofA. mexicanusinhabit in an environment devoid of light and macroscopic predation, resulting in evolved differences in diverse morphological and behavioral traits. We find that the C-start is present in multiple populations of cavefish and river-dwelling surface fish, but response kinematics and probability differ between populations. The Pachón population of cavefish have an increased response probability, a slower response and reduction of the maximum bend angle, revealing evolved differences between surface and cave populations. In two other independently evolved populations of cavefish, the response probability and the kinematics of the response differ from one another, as well as from surface fish, suggesting the independent evolution of differences in the C-start response. Investigation of surface-cave hybrids reveals a relationship between angular speed and peak angle, suggesting these two kinematic characteristics are related at the genetic or functional levels. Together, these findings provide support for the use ofA. mexicanusas a model to investigate the evolution of escape behavior.
Flexible recruitment of memory-based choice representations by human medial-frontal cortex
Authors: Minxha Juri , Adolphs Ralph , Fusi Stefano , Mamelak Adam N. , Rutishauser Ueli
Published: October 2019

Decisions in complex environments rely on flexibly utilizing past experience as required by context and instructions1. This process depends on the medial frontal cortex (MFC) and the medial temporal lobe (MTL)2-5, but it remains unknown how these structures jointly implement flexible memory retrieval6,7. We recorded single neurons in MFC and MTL while human subjects switched8 between making memory- and categorization-based decisions9,10. Here we show that MFC rapidly implements changing task demands by utilizing different subspaces of neural activity during different types of decisions. In contrast, no effect of task demands was seen in the MTL. Choices requiring memory retrieval selectively engaged phase-locking of MFC neurons to field potentials in the theta-frequency band in the MTL. Choice-selective neurons in MFC signaled abstract yes-no decisions independent of behavioral response modality (button press or saccade). These findings reveal a novel mechanism for flexibly and selectively engaging memory retrieval11-14 and show that unlike perceptual decision-making15, memory-related information is only represented in frontal cortex when choices require it.
Correlated activity favors synergistic processing in local cortical networksin vitroat synaptically-relevant timescales
Authors: Sherrill Samantha P. , Timme Nicholas M. , Beggs John M. , Newman Ehren L.
Published: October 2019

Neural information processing is widely understood to depend on correlations in neuronal activity. However, whether correlation is favorable or not is contentious. Here, we sought to determine how correlated activity and information processing are related in cortical circuits. Using recordings of hundreds of spiking neurons in organotypic cultures of mouse neocortex, we asked whether mutual information between neurons that feed into a common third neuron increased synergistic information processing by the receiving neuron. We found that mutual information and synergistic processing were positively related at synaptic timescales (0.05-14 ms), where mutual information values were low. This effect was mediated by the increase in information transmission—of which synergistic processing is a component—that resulted as mutual information grew. However, at extrasynaptic windows (up to 3000 ms), where mutual information values were high, the relationship between mutual information and synergistic processing became negative. In this regime, greater mutual information resulted in a disproportionate increase in redundancy relative to information transmission. These results indicate that the emergence of synergistic processing from correlated activity differs according to timescale and correlation regime. In a low-correlation regime, synergistic processing increases with greater correlation, and in a high correlation regime, synergistic processing decreases with greater correlation.

AUTHOR SUMMARY

In the present work, we address the question of whether correlated activity in functional networks of cortical circuits supports neural computation. To do so, we combined network analysis with information theoretic tools to analyze the spiking activity of hundreds of neurons recorded from organotypic cultures of mouse somatosensory cortex. We found that, at timescales most relevant to direct neuronal communication, neurons with more correlated activity predicted greater computation, suggesting that correlated activity does support computation in cortical circuits. Importantly, this result reversed at timescales less relevant to direct neuronal communication, where even greater correlated activity predicted decreased computation. Thus, the relationship between correlated activity and computation depends on the timescale and the degree of correlation in neuronal interactions.
State anxiety biases estimates of uncertainty during reward learning in volatile environments
Authors: Hein Thomas P , Weber Lilian A , de Fockert Jan , Ruiz Maria Herrojo
Published: October 2019

Previous research established that clinical anxiety impairs decision making and that high trait anxiety interferes with learning rates. Less understood are the effects of temporary anxious states on learning and decision making in healthy populations. Here we follow proposals that anxious states in healthy individuals elicit a pattern of aberrant behavioural, neural, and physiological responses comparable with those found in anxiety disorders, particularly when processing uncertainty in unstable environments. In our study, both a state anxious and a control group learned probabilistic stimulus-outcome mappings in a volatile task environment while we recorded their electrophysiological (EEG) signals. By using a hierarchical Bayesian model, we assessed the effect of state anxiety on Bayesian belief updating with a focus on uncertainty estimates. State anxiety was associated with an underestimation of environmental and informational uncertainty, and an increase in uncertainty about volatility estimates. Anxious individuals deemed their beliefs about reward contingencies to be more precise and to require less updating, ultimately leading to impaired reward-based learning. We interpret this pattern as evidence that state anxious individuals are less tolerant to informational uncertainty about the contingencies governing their environment and more uncertain about the level of stability of the world itself. Further, we tracked the neural representation of belief update signals in the trial-by-trial EEG amplitudes. In control participants, both lower-level precision-weighted prediction errors (pwPEs) about the reward outcomes and higher-level volatility-pwPEs were represented in the ERP signals with an anterior distribution. A different pattern emerged under state anxiety, where a neural representation of pwPEs was only found for updates about volatility. Expanding previous computational work on trait anxiety, our findings establish that temporary anxious states in healthy individuals impair reward-based learning in volatile environments, primarily through changes in uncertainty estimates and potentially a degradation of the neuronal representation of hierarchically-related pwPEs, considered to play a central role in current Bayesian accounts of perceptual inference and learning.
The paternally imprinted geneSnord116regulates cortical neuronal activity
Authors: Marta Pace , Ilaria Colombi , Matteo Falappa , Freschi Andrea , Bandarabadi Mojtaba , Andrea Armirotti , Encarnación Blanco María , Adamantidis Antoine R. , Roberto Amici , Matteo Cerri , Michela Chiappalone , Valter Tucci
Published: October 2019

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder that is characterized by rapid eye movement (REM) sleep abnormalities. The disease is caused by genomic imprinting defects that are inherited through the paternal line. Among the genes located in the PWS region on chromosome 15 (15q11-q13), small nucleolar RNA 116 (Snord116) has been previously associated with intrusions of REM sleep into wakefulness in both humans and mice.

Here, we further explore the processes of sleep regulation by studying the PWScrm+/p-mouse line, which carries a paternal deletion ofSnord116.We focused on microstructural electrophysiological components of sleep, such as REM sleep features and sleep spindles within NREM sleep. While the former are thought to contribute to neuronal network formation early in brain development, the latter are markers of thalamocortical processes. Both signals are often compromised in neurodevelopmental disorders and influence functional properties of cortical neurons. Thus, we isolated and characterized the intrinsic activity of cortical neurons usingin vitromicroelectrode array (MEA) studies.

Our results indicate that theSnord116gene in mice selectively influences REM sleep properties, such as theta rhythms and the organization of REM episodes throughout sleep-wake cycles. Moreover, sleep spindles present specific abnormalities in PWS model systems, indicating that these features of sleep may translate as potential biomarkers in human PWS. We observed abnormalities in the synchronization of cortical neuronal activity that are accounted for by high levels of norepinephrine.

In conclusion, our results provide support for an important role ofSnord116in regulating brain activity during sleep and, in particular, cortical neuronal properties, thereby opening new avenues for developing interventions in PWS.

Significance Statement

We found that theSnord116gene, a major player in Prader-Willi syndrome (PWS), significantly impacts REM sleep and its regulation. Additionally, we found that sleep spindles, a subtle electroencephalography (EEG) marker that occurs during NREM sleep, are dysregulated in PWS mice that carry a paternal deletion of theSnord116gene. Using a combination ofin vivoandin vitroexperiments, we identified sleep features at the network and molecular level that suggest thatSnord116is fundamental in the synchronization of neuronal networks. Our study also provides a new pre-clinical tool to investigate the pathophysiology of sleep in PWS.
Interactions between calmodulin and neurogranin govern the dynamics of CaMKII as a leaky integrator
Authors: Ordyan Mariam , Bartol Tom , Kennedy Mary , Rangamani Padmini , Sejnowski Terrence
Published: October 2019

Calmodulin-dependent kinase II (CaMKII) has long been known to play an important role in learning and memory as well as long term potentiation (LTP). More recently it has been suggested that it might be involved in the time averaging of synaptic signals, which can then lead to the high precision of information stored at a single synapse. However, the role of the scaffolding molecule, neurogranin (Ng), in governing the dynamics of CaMKII is not yet fully understood. In this work, we adopt a rule-based modeling approach through the Monte Carlo method to study the effect ofCa2+signals on the dynamics of CaMKII phosphorylation in the postsynaptic density (PSD). Calcium surges are observed in synaptic spines during an EPSP and back-propagating action potential due to the opening of NMDA receptors and voltage dependent calcium channels. We study the differences between the dynamics of phosphorylation of CaMKII monomers and dodecameric holoenzymes. The scaffolding molecule Ng, when present in significant concentration, limits the availability of free calmodulin (CaM), the protein which activates CaMKII in the presence of calcium. We show that it plays an important modulatory role in CaMKII phosphorylation following a surge of high calcium concentration. We find a non-intuitive dependence of this effect on CaM concentration that results from the different affinities of CaM for CaMKII depending on the number of calcium ions bound to the former. It has been shown previously that in the absence of phosphatase CaMKII monomers integrate overCa2+signals of certain frequencies through autophosphorylation (Pepke et al, Plos Comp. Bio., 2010). We also study the effect of multiple calcium spikes on CaMKII holoenzyme autophosphorylation, and show that in the presence of phosphatase CaMKII behaves as a leaky integrator of calcium signals, a result that has been recently observedin vivo. Our models predict that the parameters of this leaky integrator are finely tuned through the interactions of Ng, CaM, CaMKII, and PP1. This is a possible mechanism to precisely control the sensitivity of synapses to calcium signals.
Computational correction of off-targeting for CRISPR-Cas9 essentiality screens
Authors: Perez Alexendar R. , Sala Laura , Perez Richard K. , Vidigal Joana A.
Published: October 2019

Off-target cleavage by Cas9 can confound measurements of cell proliferation/viability in CRISPR assays by eliciting a DNA-damage response that includes cell cycle arrest1-3. This gene-independent toxicity has been documented in large scale assays2-4 and shown to be a source of false-positives when libraries are populated by promiscuous guide RNAs (gRNAs)7. To address this, we developed CSC, a computational method to correct for the effect of specificity on gRNA depletion. We applied CSC to screening data from the Cancer Dependency Map and show that it significantly improves the specificity of CRISPR-Cas9 essentiality screens while preserving known gene essentialities even for genes targeted by highly pro-miscuous guides. We packaged CSC in a Python software to allow its seamless integration into current CRISPR analysis pipelines and improve the sensitivity of essentiality screens for repetitive genomic loci.
The impact of corporate reporting readability on informational efficiency
Authors: Hesarzadeh Reza , Rajabalizadeh Javad
Published: October 2019

Purpose

Informational efficiency is a fundamental aspect of capital market quality, and therefore, regulators, managers and practitioners attempt to find ways to improve the informational efficiency. Since prior studies primarily focus on the numerical attributes of corporate reporting, it is not yet adequately known whether or not the linguistic attributes of corporate reporting affect informational efficiency. Thus, the purpose of this paper is to examine whether corporate reporting readability (readability), as an important linguistic attribute of corporate reporting, affects informational efficiency.

Design/methodology/approach

To measure readability, this paper uses Fog index. Moreover, to measure informational efficiency, the paper uses stock return variance ratios.

Findings

The findings reveal a positive and significant association between readability and informational efficiency. Moreover, the findings show that the association of readability and informational efficiency is stronger for firms facing higher information asymmetry. The findings further document the spillover effect of readability, in the sense that the readability of economically related public firms affects a firm’s informational efficiency. Overall, the results support the arguments that readability enhances informational efficiency.

Originality/value

This study contributes to the literature by providing evidence on the internalities and externalities of readability in the context of informational efficiency. Thus, the study will be of interest to regulators, managers and practitioners, especially in emerging capital markets, who tend to find practical and easy ways to improve informational efficiency.
An alternative method for refined process structure trees (RPST)
Authors: Choi Yongsun , Ha N. Long , Kongsuwan Pauline , Han Kwan Hee
Published: October 2019

Purpose

The refined process structure tree (RPST), the hierarchy of non-overlapping single-entry single-exit (SESE) regions of a process model, has been utilized for better comprehension and more efficient analysis of business process models. Existing RPST methods, based on the triconnected components of edges, fail to identify a certain type of SESE region. The purpose of this paper is to introduce an alternative method for generating a complete RPST utilizing rather simple techniques.

Design/methodology/approach

The proposed method first focuses on the SESE regions of bonds and rigids, from the innermost ones to the outermost ones, utilizing dominance and post-dominance relations. Then, any SESE region of a series nested in a bond or a rigid is identified with a depth-first search variation. Two-phase algorithms and their completeness proofs, a software tool incorporating visualization of stepwise outcomes, and the experimental results of the proposed method are provided.

Findings

The proposed method utilizes simple techniques that allow their straightforward implementation. Visualization of stepwise outcomes helps process analysts to understand the proposed method and the SESE regions. Experiments with 604 SAP reference models demonstrated the limitation of the existing RPST methods. The proposed method, however, completely identified all types of SESE regions, defined with nodes, in less computation time than with the old methods.

Originality/value

Each triconnected component of the undirected version of a process model is associated with a pair of boundary nodes without discriminating between the entry and the exit. Here, each non-atomic SESE region is associated with two distinct entry and exit nodes from the original model in the form of a directed graph. By specifying the properties of SESE regions in more comprehensible ways, this paper facilitates a deeper understanding of SESE regions rather than relying on the resulting RPST.
A critical examination of the social impacts of large multinational corporations in the age of globalization
Authors: Yeganeh Hamid
Published: October 2019

Purpose

This paper aims to offer a critical examination of the social impacts of large multinational corporations (MNCs) in the age of globalization.

Design/methodology/approach

The study adopts a multidisciplinary approach and relies on various scholarly resources in several disciplines including international business, international economics, sociology and international relations. The analysis is organized around eight major areas and constituencies of MNCs including the global scene, workers, competitors, entrepreneurs, government and tax payers, social justice, nations/states and natural environment.

Findings

Giant MNCs have benefited from favorable conditions in the past three decades and currently dominate the global scene. In general, the rising corporate profits come not to the benefit, but to the detriment of workers. Large MNCs benefit from their immense resources to develop sophisticated competitive advantages against smaller rivals. They impede small entrepreneurs from scaling up their operations and increasing their market shares. Furthermore, large MNCs often take advantage of their power to shape national and international policies in ways that enable them to enhance their profitability. Overall, large MNCs aggravate the rising economic inequality in different ways, thus contributing to social and financial instability. Furthermore, large MNCs erode state sovereignty and enormously contribute to environmental degradation.

Originality/value

While most international business studies focus on the concept of corporate social responsibility or sustainable development, the originality of this paper resides in adopting an alternative perspective and offering a multidisciplinary and critical examination of the social impacts of large MNCs.
Terrorism risk and optimal policy response: theory and empirics
Authors: Mohtadi Hamid , Weber Bryan
Published: October 2019

Purpose

The proliferation of terrorism worldwide raises the risk that terrorist strategies could evolve from conventional methods (e.g. suicide attacks) to biological, chemical and even radioactive and nuclear attacks (commonly abbreviated as CBRN) which are potentially much more dangerous. The authors make three contributions toward a better understanding of this risk and how it responds to counterterrorism measures.

Design/methodology/approach

The authors develop a game that captures the terrorists’ potential strategic substitution between conventional and CBRN-type attacks; the authors calibrate the parameters of the game to real data using a novel calibration method and a partially unique dataset; they estimate the heavy-tailed distribution of attack severity and thus the probability of a successful attack, the underlying effort to launch an attack and the intrinsic difficulty of launching different types of attacks.

Findings

The authors find that in equilibrium, CBRN attacks, though less likely and more difficult to execute, are more deadly. In the end, the trade-off between, on one hand, the greater difficulty of carrying out a CBRN attack, and on the other, the greater deadliness of such an attack, points to a level of optimal counterterrorism spending by governments that weighs toward defending against CBRN attacks. The authors discuss these results and compare them with the actual level of counterterrorism spending by the US Government.

Originality/value

The framework of the game allows for substitution between the conventional and CBRN weapon types. These aspects of this paper, together with the unique calibration methodology, and the use of some unique terrorism data for the first time, are what distinguish this work from similar game theoretic papers in this area.
Geographic distance and goodwill impairment
Authors: Harper Joel , Sun Li
Published: October 2019

Purpose

The purpose of this study is to examine the impact of asymmetric information, estimated as the geographic distance between the acquiring firm and the target firm, on goodwill impairment following a merger or acquisition.

Design/methodology/approach

This study uses regression analysis to investigate the research questions of this study.

Findings

This study finds that geographic distance is positively related to the magnitude of current and cumulative goodwill impairment. The results of this study still hold even after robustness checks for other factors that affect mergers and acquisitions and sources of asymmetric information.

Originality/value

This study extends and links two distinct research streams: asymmetric information related to geographic distance studies in finance and goodwill literature in accounting. Specifically, this study extends literature on the impact of geographic distance on various firm characteristics and contributes to research regarding the determinants of goodwill impairment, a major research stream in goodwill accounting (Li and Sloan, 2016). To the best of the authors’ knowledge, this is the first study that performs a direct empirical test on the relation between geographic distance (between the acquiring firm and the target firm) and goodwill impairment.
Ownership and dynamic efficiency of petroleum firms: a new perspective
Authors: Asuah Evelyn Lamisi , Ohene-Asare Kwaku
Published: October 2019

Purpose

The purpose of this study is to examine efficiency differences among petroleum firms based on their ownership status, with the aim of helping these firms understand how specific levels of state-ownership affects efficiency and to bring new perspective to the ownership-performance literature.

Design/methodology/approach

The study uses ten-year data (2001-2010) of 32 global petroleum firms categorized into four groups based on ownership types. The metafrontier analysis is used with the dynamic slack-based measure to estimate dynamic efficiency differences among the groups while respectively, accounting for carryover variables such as oil and gas reserves.

Findings

Fully state-owned firms outperformed private, majority and minority state-owned firms, indicating that not all types of state-owned petroleum firms are outperformed by private firms. Additionally, firms with shared ownership between state and private are seen to have a lesser comparative advantage in the industry than those with full private or state ownership.

Practical implications

Jointly owned petroleum firms should consider converting ownership to either full private or full state control. Conflict management measures should be used to handle possible conflicts between different shareholding groups.

Originality/value

This is among the first studies to sub-group state ownership into various levels to comprehensively examine specific levels of state ownership that is detrimental to the performance of petroleum firms. It is also the premier oil efficiency study to use the metafrontier framework to cater for group heterogeneity. The study treats oil and gas reserves as interconnecting variables that are not consumed only in the period for which they are discovered to ensure fair assessment.
Data replication techniques in the mobile ad hoc networks
Authors: Abdollahi Nami A. , Rajabion L.
Published: October 2019

Purpose

A mobile ad hoc network (MANET) enables providers and customers to communicate without a fixed infrastructure. Databases are extended on MANETs to have easy data access and update. As the energy and mobility limitations of both servers and clients affect the availability of data in MANETs, these data are replicated. The purpose of this paper is to provide a literature review of data replication issues and classify the available strategies based on the issues they addressed.

Design/methodology/approach

The selected articles are reviewed based on the defined criteria. Also, the differences, the advantages and disadvantages of these techniques are described. The methods in the literature can be categorized into three groups, including cluster-based, location-based and group-based mechanisms.

Findings

High flexibility and data consistency are the features of cluster-based mechanisms. The location-based mechanisms are also appropriate for replica allocation, and they mostly have low network traffic and delay. Also, the group-based mechanism has high data accessibility compared to other mechanisms. Data accessibility and time have got more attention to data replication techniques. Scalability as an important parameter must be considered more in the future. The reduction of storage cost in MANETs is the main goal of data replication. Researchers have to consider the cost parameter when another parameter will be influenced.

Research limitations/implications

Data replication in MANETs has been covered in different available sources such as Web pages, technical reports, academic publications and editorial notes. The articles published in national journals and conferences are ignored in this study. This study includes articles from academic main international journals to get the best capability.

Originality/value

The paper reviews the past and the state-of-the-art mechanisms in data replication in MANET. Exclusively, data replication’s main goal, existing challenges, research terminologies and mechanisms in MANET are summarized using the answers to the research questions. This method will help researchers in the future to develop more effective data replication method in MANET.
Financial capabilities development: essential discourse in social work
Authors: Engelbrecht Lambert K. , Ornellas Abigail
Published: October 2019

Purpose

Within a neoliberal environment, financial vulnerability of households has become an increasing challenge and there is a requirement of financial literacy education, a necessary activity to facilitate sustainable development and well-being. However, this is seldom a mainstream discourse in social work deliberations. The paper aims to discuss these issues.

Design/methodology/approach

First, introducing the neoliberal impact on financial well-being and capability for vulnerable households, the authors’ postulation is substantiated on a seven-point argument. The contexts of financially vulnerable households are sketched. Second, a conceptualisation of financial literacy is offered, and third, perspectives on and approaches to financial literacy as a fundamental capability are presented. This is followed by a theoretical foundation of community education as a practice model in social work to develop financial capabilities. In the fifth place, prevailing practices of Financial Capabilities Development (FCD) programmes are offered. Subsequently, the implications of a neoliberal environment for social work practice are examined.

Findings

The revised global definition of social work encourages the profession to understand and address the structural causes of social problems through collective interventions. As a response, it is argued that community education towards FCD of vulnerable households within a neoliberal environment should be an essential discourse in social development.

Originality/value

The authors reflect on the significance of FCD, highlighting its contribution towards human security and sustainable development. Although this paper draws on Southern African contexts, the discourse finds resonance in other contexts across the world.
Sliding energy of textured surfaces via pendular tests
Authors: Ferri Gabriel , Dias Leonardo , de Carvalho Ruan , Costa Henara
Published: October 2019

Purpose

Surface texturing can improve the tribological performance of contacting sliding surfaces under different contact and lubrication conditions, which has been proved both numerically and experimentally. This study aims to suggest a new methodology to evaluate the tribological behavior of textured surfaces using an adapted pendular scratch tester.

Design/methodology/approach

A Charpy-type tester was adapted to meet conditions that are relevant for sliding surfaces. The test rig was used to evaluate low carbon steel textured surfaces produced via maskless electrochemical texturing. The textures were composed of 100 pockets with an average diameter of 200 µm of and variable average depths (1.5, 3.5 and 7 µm). The tests were performed under dry and lubricated conditions for smooth and textured surfaces. The lubricated tests simulated a starved condition by applying a drop of lubricant.

Findings

For starved lubrication, surface texturing reduced the sliding energy when compared with smooth surfaces. This was attributed to the pocket’s ability to provide an additional supply of lubricant, as well as a reduced amount of plastic deformation around the pockets during sliding of the indenter. However, under dry sliding conditions, no significant effect of surface texturing was detected.

Originality/value

A new evaluation methodology was proposed, using single-pass pendular sliding of a spherical indenter to measures the energy absorbed during sliding, which was referred to as sliding energy. The measurements are repeatable and can detect sliding energy differences between smooth and textured surfaces.
When face meets globalization
Authors: Huang Haiyang , He Jiaxun
Published: October 2019

Purpose

Synthesizing the unique Confucian cultural values and the common characteristics of emerging markets, the purpose of this paper is to examine how face drives consumers’ attitudes toward global consumer culture positioning (GCCP) as well as the moderating roles of social aggrandizement and susceptibility to normative influence (SNI).

Design/methodology/approach

The authors adopt the total effect moderation model to test the hypotheses using data collected from China.

Findings

The results show that face positively affects consumers’ attitudes toward GCCP through enhancing their pursuit for global myth. In addition, social aggrandizement positively moderates the influence of face on pursuit for global myth. SNI positively moderates the influence of pursuit for global myth on attitudes toward GCCP.

Practical implications

The findings of this study highlight the need to utilize local powers to promote brands globally and provide guidelines for “Think Globally, Act Locally” in Confucian societies.

Originality/value

This study represents an important step in the global branding literature regarding the advancement of culturally driven attitudes toward GCCP by taking root in the Confucian culture.
The business model of Chinese movies
Authors: Chen Man , Han Xiaomin , Zhang Xinguo , Wang Feng
Published: October 2019

Purpose

The motion picture industry is a cultural and creative industry. Unlike its US counterpart, the Chinese motion picture industry is still developing. Therefore, learning from the US market, the purpose of this paper is to analyze the business model of Chinese movies from the perspective of new product diffusion.

Design/methodology/approach

Based on 66 movies released in the US and 21 movies released in China, this paper first compares the diffusion curves of Chinese and US movies through the movie life cycle and box office trends. Next, it analyzes the moviegoing behaviors of Chinese and US audiences based on the innovation and imitation coefficients in the Bass model. Finally, it compares the attention to information of Chinese and US audiences from the perspective of interpersonal word-of-mouth (WOM).

Findings

In the USA, a movie’s highest weekly box office is usually in its opening week, followed by a weekly decline in revenue; in China, there is no difference in box office performance between the first two weeks, but a weekly decline in revenue similarly follows. US audiences pay more attention to advertisements for movies than WOM recommendations, while Chinese people pay more attention to WOM recommendations. Neither the Chinese nor the US market differs in the volume of WOM between the first week before release and the opening week, and these two weeks are the most active period of WOM in both markets.

Practical implications

During the production phase for Chinese movies, we should satisfy opinion leaders’ needs. During the distribution phase, we should not only focus on market spending before the movie’s release, but also increase market spending in the opening week. During the theater release phase, we should stimulate WOM communication between moviegoers and thereby attract many more opinion seekers.

Originality/value

Few studies have investigated the Chinese motion picture industry from the perspective of new products. This paper compares and analyzes the diffusion of Chinese and US movies using the Bass model of new product diffusion, providing systematic theoretical guidelines for the commercial operation of the Chinese motion picture industry.
The effect of outside blockholders on earnings management around seasoned equity offerings in French listed companies on the SBF120
Authors: Jerbi Maatougui Abir , Halioui Khamoussi
Published: October 2019

Purpose

The purpose of this study is to test the effect of the presence of outside blockholders on earnings management around seasoned equity offerings (SEOs).

Design/methodology/approach

Given that SEO can be one of motivations for earnings management, the authors examined the role of outside blockholders in monitoring the opportunistic behavior of managers around 50 SEOs realized by 45 French companies during the 2005-2009 period based on panel data model.

Findings

The authors found that issuing firms are used for upward earnings management during the pre-offering period. Indeed, the discretionary accruals know a continuous evolution during the three years preceding SEO and peaked in the year prior to the SEO. This result led us to examine the role played by the outside blockholders on earnings management. The results provided empirical evidence that the presence of outside blockholders in SEO firms is able to restrain earnings management practices.

Research limitations/implications

This study allows to inform investors that French issuing firms are less overvalued in the presence of outside blockholders than in their absence. As a result, investors have an interest in participating in the SEO of firms that hold outside blockholders in their capital structure. Again, based on this study, users of financial statements can trust the reliability of the financial statements published by companies with outside blockholders because of the careful control exercised by these shareholders in the process of producing financial information. However, similar to how any research may suffer from some limitations, this work has two major limitations. Firstly, the authors examined the impact of outside blockholders on earnings management without distinguishing between the different types of blockholders (such as individual investors, pension funds, mutual funds, banks and trusts). Secondly, they have estimated the discretionary accruals by referring to a single model (Kothariet al., 2007). However, the use of two or more models for estimating accruals will lead to more robust results.

Originality/value

The empirical literature emphasizes the monitoring role played by these shareholders on earnings management. However, it does not distinguish between the circumstances when the monitors either lose or win from exaggerations. This research completes this lack by studying the impact of outside blockholders on earnings management around SEOs.
Firm characteristics and compliance with IAS/IFRS
Authors: Alnaas Ali , Rashid Afzalur
Published: October 2019

Purpose

This paper aims to examine the influence of firm characteristics on harmonisation of companies listed on the Egypt, Morocco and Tunisia Stock Exchanges.

Design/methodology/approach

This study uses a checklist based mainly on the International Financial Reporting Standards (IFRS).

Findings

The findings of the study are 6that the level of compliance with IFRS was higher in 2010 than in 2005. Multiple regression analysis indicates that the level of compliance with IFRS increases with company size, institutional ownership, industry and language of disclosure.

Research limitations/implications

The findings of this study suggest that both institutional- and firm-level forces influence the harmonisation process.

Originality/value

This study contributes to the literature on accounting harmonisation in the context of North Africa.