bluuebunny/crossref_metadata_2025 huggingface dataset:
Hippocampal theta coordinates memory processing during visual exploration
Authors: Kragel James E. , VanHaerents Stephen , Templer Jessica W. , Schuele Stephan , Rosenow Joshua M. , Nilakantan Aneesha S. , Bridge Donna J.
Published: May 2019

The hippocampus supports memory encoding and retrieval, with distinct phases of theta oscillations modulating the amplitude of gamma-band activity during each process. Encoding and retrieval operations dynamically interact over rapid timescales, especially when sensory information conflicts with memory. The ability to link hippocampal dynamics to specific memory-guided behaviors has been limited by experiments that lack the temporal resolution to segregate when encoding and retrieval occur. To resolve this issue, we simultaneously tracked eye movements and hippocampal field potentials while neurosurgical patients performed a spatial memory task. Novelty-driven fixations increased phase-locking to the theta rhythm, which predicted successful memory performance. Theta to gamma phase amplitude coupling increased during these viewing behaviors and predicted forgetting of conflicting memories. In contrast, theta phase-locking preceded fixations initiated by memory retrieval, indicating that the hippocampus coordinates memory-guided eye movements. These findings suggest that theta oscillations in the hippocampus support learning through two interleaved processes: strengthening the encoding of novel information and guiding exploration based on prior experience.
Synthetic peptide-induced internalization of biomolecules into various plant and algal cells via micropinocytosis
Authors: Chuah Jo-Ann , Odahara Masaki , Kodama Yutaka , Miyamoto Takaaki , Tsuchiya Kousuke , Motoda Yoko , Kigawa Takanori , Numata Keiji
Published: May 2019

Efficient intracellular delivery of biomolecules is important for many different biological and biotechnological applications in living organisms, and is a prerequisite for certain types of fundamental and applied research. One major challenge is the delivery of unmodified, functional cargoes in a simple, time-efficient, and high-throughput manner. Herein, we present an efficient strategy that uses fusion peptides containing cell penetrating peptide, endosomal escape domain, and a sarcosine linker to introduce biomolecules, namely fluorescent protein and dextran, via macropinocytosis into the cells of various land plants and microalgae. Our peptide-mediated delivery system allows for high-throughput delivery of functional biomolecules within a few minutes to a few hours as well as open new possibilities for biology and biotechnology using difficult-to-transfect cell types.
Transcranial alternating current stimulation attenuates BOLD adaptation and increases functional connectivity
Authors: Kar Kohitij , Ito Takuya , Cole Michael , Krekelberg Bart
Published: May 2019

Transcranial alternating current stimulation (tACS) is used as a non-invasive tool for cognitive enhancement and clinical applications. The physiological effects of tACS, however, are complex and poorly understood (Liu et al. 2018). Most studies of tACS focus on its ability to entrain brain oscillations (Herrmann et al. 2013), but our behavioral results in humans (Kar and Krekelberg 2014a) and extracellular recordings in nonhuman primates (Kar et al. 2017) support the view that tACS at 10 Hz additionally affects brain function by reducing sensory adaptation. Our primary goal here was to test this hypothesis using BOLD imaging in human subjects. Using a motion adaptation paradigm developed to quantify BOLD adaptation (Huk et al. 2001) and concurrent fMRI and tACS, we found that tACS significantly attenuated adaptation in the human motion area (hMT+). In addition, an exploratory analysis showed that tACS increased functional connectivity between the stimulated hMT+ and the rest of the brain, in particular the dorsal attention network. We conclude that weak 10 Hz currents applied to the scalp affect both local and global measures of brain activity.

New and Noteworthy

Concurrent transcranial alternating current stimulation (tACS) and fMRI show that tACS affects the human brain by attenuating adaptation and increasing functional connectivity. This work is important for our basic understanding of what tACS does, but also for therapeutic applications, which need insight into the full range of ways in which tACS affects the brain.
The plastidial exporter Enhanced Disease Susceptibility 5 is required for the biosynthesis ofN-hydroxy pipecolic acid
Authors: Rekhter Dmitrij , Mohnike Lennart , Feussner Kirstin , Zienkiewicz Krzysztof , Zhang Yuelin , Feussner Ivo
Published: May 2019

Pipecolic acid is essential for the establishment of systemic acquired resistance in plants. It is synthesized in the plastid and further processed in the cytosol to its active form N-hydroxy pipecolic acid. Here we provide strong evidence that the exporter Enhanced Disease Susceptibility 5 is required for the biosynthesis of not only salicylic acid, but also N-hydroxy pipecolic acid, suggesting that it represents a convergent point of plant immunity.
Computational staining of pathology images to study tumor microenvironment in lung cancer
Authors: Wang Shidan , Rong Ruichen , Yang Donghan M. , Cai Ling , Yang Lin , Luo Danni , Yao Bo , Xu Lin , Wang Tao , Zhan Xiaowei , Xie Yang , Gazdar Adi , Minna John , Xiao Guanghua
Published: May 2019

The spatial organization of different types of cells in tumor tissues reveals important information about the tumor microenvironment (TME). In order to facilitate the study of cellular spatial organization and interactions, we developed a comprehensive nuclei segmentation and classification tool to characterize the TME from standard Hematoxylin and Eosin (H&E)-stained pathology images. This tool can computationally “stain” different types of cell nuclei in H&E pathology images to facilitate pathologists in analyzing the TME.

A Mask Regional-Convolutional Neural Network (Mask-RCNN) model was developed to segment the nuclei of tumor, stromal, lymphocyte, macrophage, karyorrhexis and red blood cells in lung adenocarcinoma (ADC). Using this tool, we identified and classified cell nuclei and extracted 48 cell spatial organization-related features that characterize the TME. Using these features, we developed a prognostic model from the National Lung Screening Trial dataset, and independently validated the model in The Cancer Genome Atlas (TCGA) lung ADC dataset, in which the predicted high-risk group showed significantly worse survival than the low-risk group (pv= 0.001), with a hazard ratio of 2.23 [1.37-3.65] after adjusting for clinical variables. Furthermore, the image-derived TME features were significantly correlated with the gene expression of biological pathways. For example, transcription activation of both the T-cell receptor (TCR) and Programmed cell death protein 1 (PD1) pathways was positively correlated with the density of detected lymphocytes in tumor tissues, while expression of the extracellular matrix organization pathway was positively correlated with the density of stromal cells.

This study developed a deep learning-based analysis tool to dissect the TME from tumor tissue images. Using this tool, we demonstrated that the spatial organization of different cell types is predictive of patient survival and associated with the gene expression of biological pathways. Although developed from the pathology images of lung ADC, this model can be adapted into other types of cancers.
A domain-resolution map ofin vivoDNA binding reveals the regulatory consequences of somatic mutations in zinc finger transcription factors
Authors: Dogan Berat , Kailasam Senthilkumar , Corchado Aldo Hernández , Nikpoor Naghmeh , Najafabadi Hamed S.
Published: May 2019

Multi-zinc finger proteins constitute the largest class of human transcription factors. Their DNA-binding specificity is usually encoded by a subset of their tandem Cys2His2 zinc finger (ZF) domains – the subset that binds to DNA, however, is often unknown. Here, by combining a context-aware machine-learning-based model of DNA recognition within vivobinding data, we characterize the sequence preferences and the ZF subset that is responsible for DNA binding in 209 human multi-ZF proteins. We show thatin vivoDNA binding is primarily driven by ∼50% of the ZFs – these DNA-binding ZFs are under strong selective pressure within and across species, and their mutations affect the expression of hundreds of genes as revealed by pan-cancer trans-eQTL analysis across 18 tissues. Among the genes affected by mutations in multi-ZF proteins, we identify several oncogenic factors regulated by SP1, and show that SP1 up-regulation in cancer promotes the expression of these genes while mutations in SP1 ZFs lead to their repression. Together, these analyses suggest that mutations in DNA-binding ZFs have distinct and widespread regulatory consequences that contribute to transcriptome remodelling in cancer.
Ablation catheter motion detection during contact force and VISITAG™ Module-guided pulmonary vein isolation
Authors: Tomlinson David R , Biscombe Katie , True John , Hosking Joanne , Streeter Adam J
Published: May 2019

Background: During contact force (CF) and VISITAG™ Module (Biosense Webster) guided pulmonary vein isolation (PVI), ACCURESP™ respiratory motion adjustment is recommended, although without in vivo validation.
Objective: Since accurate LAPW radiofrequency (RF) annotation is crucial to avoid oesophageal thermal injury, we compared ACCURESP™ setting ("on" versus "off") on RF annotation at the left atrial posterior wall (LAPW).
Methods: From a twenty-five patient cohort undergoing CF PVI (continuous RF, 30W) using general anaesthesia and VISITAG™ Module annotation-guidance (force-over-time 100% minimum 1g, 2mm position stability, ACCURESP™ "off"), respiratory motion detection occurred in eight, permitting retrospective comparison of ACCURESP™ settings.
Results: There were significant differences in LAPW RF data annotation according to ACCURESP™ setting. Comparing ACCURESP™ "on" versus "off", respectively: Total annotated sites 82 versus 98; Median RF duration per-site 13.3s versus 10.6s (p<0.0001); Median force time integral 177g.s versus 130g.s (p=0.0002); Mean inter-lesion distance (ILD) 6.0mm versus 4.8mm (p=0.002). Considering only annotated site 1-to-2 transitions, three occurred with 0g CF; ACCURESP™ "on" minus "off" difference in RF duration was <0.6s. However, thirteen site 1-to-2 transitions during constant catheter-tissue contact (ILD range 2.1 - 7.0mm) demonstrated a mean difference in annotated RF duration at site 1, of 3.7s (Range: -1.3 - 11.3s). Reconstituted curves displaying catheter position data, CF, impedance and site 1-to-2 transition according to ACCURESP™ setting, demonstrated multiple markers of catheter movement coinciding with ACCURESP™ "off".
Conclusions: ACCURESP™ "off" setting demonstrated excellent catheter movement detection properties and represents an optimal method towards the annotation of stable sites of RF delivery at the LAPW.
Accelerated phosphatidylcholine turnover in macrophages promotes adipose tissue inflammation in obesity
Authors: Petkevicius Kasparas , Virtue Samuel , Bidault Guillaume , Jenkins Benjamin , Çubuk Cankut , Morgantini Cecilia , Aouadi Myriam , Dopazo Joaquin , Serlie Mireille , Koulman Albert , Vidal-Puig Antonio
Published: May 2019

White adipose tissue (WAT) inflammation contributes to the development of insulin resistance in obesity. While the role of adipose tissue macrophage (ATM) pro-inflammatory signalling in the development of insulin resistance has been established, it is less clear how WAT inflammation is initiated. Here, we show that ATMs from obese mice and humans exhibit markers of increased de novo phosphatidylcholine (PC) biosynthesis rate. Macrophage-specific knockout of phosphocholine-cytidylyltransferase A (CCTα), the rate-limiting enzyme of de novo PC biosynthesis pathway, alleviated obesity-induced WAT inflammation and insulin resistance. Mechanistically, CCTα-deficient macrophages showed reduced ER stress and inflammation in response to palmitate. Surprisingly, this was not due to lower exogenous palmitate incorporation into cellular PCs. Instead, CCTα-null macrophages had lower PC turnover, leading to elevated membrane polyunsaturated fatty acids that negated the pro-inflammatory effects of palmitate. Our results reveal a link between obesity-associated increase in PC synthesis, accelerated PC turnover and pro-inflammatory activation of ATMs.
Expanding the Zebrafish Genetic Code through Site-Specific Introduction of Azido-lysine, Bicyclononyne-lysine, and Diazirine-lysine
Authors: Syed Junetha , Palani Saravanan , Clarke Scott T. , Asad Zainab , Bottrill Andrew R. , Jones Alexandra M.E. , Sampath Karuna , Balasubramanian Mohan K
Published: May 2019

Site-specific incorporation of un-natural amino acids (UNAA) is a powerful approach to engineer and understand protein function [1-4]. Site-specific incorporation of UNAAs is achieved through repurposing the amber codon (UAG) as a sense codon for the UNAA, a tRNACUA that base pairs with an UAG codon in the mRNA and an orthogonal amino-acyl tRNA synthetase (aaRS) that charges the tRNACUA with the UNAA [5, 6]. Here, we report expansion of the zebrafish genetic code to incorporate the UNAAs, Azido-lysine (AzK), bicyclononyne-lysine (BCNK), and Diazirine-lysine (AbK) into green fluorescent protein (GFP) and Glutathione-S-transferase (GST). We also present proteomic evidence for UNAA incorporation into GFP. Our work sets the stage for the use of UNAA mutagenesis to investigate and engineer protein function in zebrafish.
The atypical Rho GTPase RhoU interacts with Intersectin-2 to regulate endosomal recycling pathways
Authors: Gubar Olga , Croisé Pauline , Kropyvko Sergii , Gryaznova Tetyana , Toth Petra , Blangy Anne , Vitale Nicolas , Rynditch Alla , Gasman Stéphane , Ory Stéphane
Published: May 2019

Rho GTPases play a key role in various membrane trafficking processes. RhoU is an atypical small Rho GTPase related to Rac/Cdc42 which possesses unique N- and C-terminal domains that regulate its function and its subcellular localization. RhoU localized at the plasma membrane, on endosomes and in cell adhesion structures where it governs cell signalling, differentiation and migration. However, despite its endomembrane localization, RhoU function in vesicular trafficking has been unexplored. Here, we identified intersectins (ITSNs) as new binding partners for RhoU and showed that the second PxxP motif at the N-terminus of RhoU mediated interactions with SH3 domains of ITSNs. To evaluate the function of RhoU and ITSNs in vesicular trafficking, we used fluorescent transferrin as a cargo for uptake experiments. We showed that silencing of either RhoU or ITSN2, but not ITSN1 increased transferrin accumulation in early endosomes resulting from defect in fast vesicle recycling. Concomitantly, RhoU and ITSN2 colocalized to a subset of Rab4-positive vesicles suggesting that RhoU-ITSN2 interaction may occur on fast recycling endosomes to regulate the fate of vesicular cargos.
Cerebro: Interactive visualization of scRNA-seq data
Authors: Hillje Roman , Pelicci Pier Giuseppe , Luzi Lucilla
Published: May 2019

Despite the growing availability of sophisticated bioinformatic methods for the analysis of single-cell RNA-seq data, few tools exist that allow biologists without bioinformatic expertise to directly visualize and interact with their own data and results. Here, we present Cerebro (cell report browser), a Shiny- and Electron-based standalone desktop application for macOS and Windows, which allows investigation and inspection of pre-processed single-cell transcriptomics data without requiring bioinformatic experience of the user.

Through an interactive and intuitive graphical interface, users can i) explore similarities and heterogeneity between samples and cells clusters in 2D or 3D projections such as t-SNE or UMAP, ii) display the expression level of single genes or genes sets of interest, iii) browse tables of most expressed genes and marker genes for each sample and cluster.

We provide a simple example to show how Cerebro can be used and which are its capabilities. Through a focus on flexibility and direct access to data and results, we think Cerebro offers a collaborative framework for bioinformaticians and experimental biologists which facilitates effective interaction to shorten the gap between analysis and interpretation of the data.

Availability

Cerebro and example data sets are available at https://github.com/romanhaa/Cerebro. Similarly, the R packages cerebroApp and cerebroPrepare R packages are available at https://github.com/romanhaa/cerebroApp and https://github.com/romanhaa/cerebroPrepare, respectively. All components are released under the MIT License.
Structural equation modeling for hypertension and type 2 diabetes based on multiple SNPs and multiple phenotypes
Authors: Jeon Saebom , Shin Ji-yeon , Yee Jaeyong , Park Taesung , Park Mira
Published: May 2019

Genome-wide association studies (GWAS) have been successful in identifying genetic variants associated with complex diseases. However, association analyses between genotypes and phenotypes are not straightforward due to the complex relationships between genetic and environmental factors. Moreover, multiple correlated phenotypes further complicate such analyses.

To resolve this complexity, we present an analysis using structural equation modeling (SEM). Unlike current methods that focus only on identifying direct associations between diseases and genetic variants such as single-nucleotide polymorphisms (SNPs), our method introduces the effects of intermediate phenotypes, which are related phenotypes distinct from the target, into the systematic genetic study of diseases. Moreover, we consider multiple diseases simultaneously in a single model. The procedure can be summarized in four steps: 1) selection of informative SNPs, 2) extraction of latent variables from the selected SNPs, 3) investigation of the relationships among intermediate phenotypes and diseases, and 4) construction of an SEM. As a result, a quantitative map can be drawn that simultaneously shows the relationship among multiple SNPs, phenotypes, and diseases.

In this study, we considered two correlated diseases, hypertension and type 2 diabetes (T2D), which are known to have a substantial overlap in their disease mechanism and have significant public health implications. As intermediate phenotypes for these diseases, we considered three obesity-related phenotypes—subscapular skin fold thickness, body mass index, and waist circumference—as traits representing subcutaneous adiposity, overall adiposity, and abdominal adiposity, respectively. Using GWAS data collected from the Korea Association Resource (KARE) project, we applied the proposed SEM process. Among 327,872 SNPs, 24 informative SNPs were selected in the first step (p<1.0E-05). Ten latent variables were generated in step 2. After an exploratory analysis, we established a path diagram among phenotypes and diseases in step 3. Finally, in step 4, we produced a quantitative map with paths moving from specific SNPs to hypertension through intermediate phenotypes and T2D. The resulting model had high goodness-of fit measures (χ2= 536.52, NFI=0.997, CFI=0.998).
Paternal kin discrimination by sons in male chimpanzees transitioning to adulthood
Authors: Sandel Aaron A. , Mitani John C. , Langergraber Kevin E.
Published: May 2019

Although paternal investment explains the evolution of fatherhood from a functional perspective, its evolutionary origins are unclear. Here we investigate whether a building block for paternal investment, father-offspring discrimination, is present in our closest living relatives, chimpanzees. Adolescent and young adult males (12 - 21 years old) maintained proximity and groomed with their fathers more frequently than with other males given how often they associated. This discrimination did not likely increase the short-term inclusive fitness of fathers or sons because the absolute time they spent in proximity or grooming did not exceed the time spent in these activities by other dyads. Almost all grooming was done by sons rather than fathers, suggesting that sons are responsible for observed biases in father-son behavior. Father-offspring discrimination could partly be explained by young males socializing with males who were more likely to be their father based on their age at the time of the young male’s conception. Two other cues of paternity, the other male’s rank at the time of the young male’s infancy and the other male’s association frequency with the young male’s mother during the young male’s infancy/juvenility, failed to predict association-controlled proximity or grooming. Father-son biases persisted even after controlling for characteristics of males that predicted paternity probability, implicating other cues that we did not examine. These results suggest that an important factor for the evolution of highly investing fathers in humans, father-offspring discrimination, may have been present in simpler form in the last common ancestor they shared with chimpanzees.
Assessing the social impact of an online course on the clinical management of Cutaneous Leishmaniasis: A qualitative study
Authors: Carrion Carme , Aymerich Marta , Arroyo Liliana , Ruiz-Postigo José A
Published: May 2019

Background

In conjunction with the World Health Organization (WHO), Universitat Oberta de Catalunya (UOC) has implemented training in the treatment of cutaneous leishmaniasis (CL) for health professionals in countries where the condition is highly endemic through an interactive on-line course. With three editions of the course successfully completed, we consider assessment of the course’s social impact through analysis of the outcomes beyond knowledge acquisition to be of paramount importance.

Methodology/Principal findings

To this end, we have conducted a study using the Theory of Change theoretical approach, combined with an exploration of students’ experiences through in-depth interviews before, during and after taking the course. These testimonies have been analyzed and classified according to their type of result – outputs, outcomes and longer-term impacts – and distributed along three different levels: individual, collective (meso), and systemic change. Insights about intercultural communication in qualitative research are discussed in relation to the characteristics of UOC researchers and the class composition of faculty and students in the Middle East and North Africa countries (MENA) region.

Conclusions/Significance

This analysis fills a gap in the knowledge of social impact assessment through the establishment of a new methodological approach. The course has proven to be a valuable source of social capital and provided a space to build a network of professionals with a shared focus on how to treat CL in particular – a community of practice – and increase knowledge of other skin NTDs.

Author summary

Neglected tropical diseases (NTDs) affecting the skin (Buruli ulcer, cutaneous leishmaniasis, post-kala-azar dermal leishmaniasis, leprosy, lymphatic filariasis, mycetoma, onchocerciasis, scabies and yaws) cause considerable disability, increase stigma and exacerbate poverty. Cutaneous leishmaniasis (CL) is one of the most neglected NTDs. It has an estimated incidence of between 900,000 and 1.3 million new cases worldwide each year. A co-venture between the World Health Organization (WHO) and Universitat Oberta de Catalunya (UOC) has developed an on-line interactive course entitled “Clinical management of CL” to provide health personnel with thorough and up-to-date information on the various aspects of CL. Using a new methodological approach, we have conducted a social impact assessment of this training program in order to identify the different type and level of results. The most significant impact has been the mobilizing of students and professors from the different editions of the course in a community of practice, thereby enhancing learning, knowledge sharing and effectivity.
Determinants of FtsZ C-terminal linker-dependent regulation of cell wall metabolism in Caulobacter crescentus
Authors: Sundararajan Kousik , Barrows Jordan M. , Goley Erin D.
Published: May 2019

Bacterial cell division requires assembly of a multi-protein machinery or “divisome” that remodels the cell envelope to cause constriction. The cytoskeletal protein FtsZ forms a ring-like scaffold for the divisome at the incipient division site. FtsZ has three major regions – a conserved, polymerizing GTPase domain; a C-terminal conserved (CTC) peptide required for binding membrane-anchoring proteins; and a C-terminal linker (CTL) of poor length and sequence conservation. We previously demonstrated that, in Caulobacter crescentus, the CTL regulates FtsZ polymerization in vitro and cell wall metabolism in vivo. To understand the mechanism of CTL-dependent regulation of cell wall metabolism, here we investigated the impact of the CTL on Z-ring structure in cells and employed genetics to identify molecular determinants of the dominant lethal effects of ΔCTL. Deleting the CTL specifically resulted in formation of dense, asymmetric, non-ring FtsZ assemblies in vivo. Moreover, we observed that production of an FtsZ variant with the GTPase domain of Escherichia coli FtsZ fused to the CTC of C. crescentus FtsZ phenocopied the effects of C. crescentus ΔCTL, suggesting the CTC mediates signaling to cell wall metabolism. Finally, whereas overproduction of ZapA, FzlC, or FtsEX had slight protective effects against ΔCTL, depletion of FtsA partially suppressed the effects of ΔCTL. From these results, we propose that the cell wall misregulation downstream of ΔCTL results from its aberrant assembly properties and is propagated through the interaction between the CTC of FtsZ and FtsA. Our study provides mechanistic insights into CTL-dependent regulation of cell wall enzymes downstream of FtsZ.

Importance

Bacterial cell division is essential and requires the recruitment and regulation of a complex network of proteins needed to initiate and guide constriction and cytokinesis. FtsZ serves as a master regulator for this process, and its function is highly dependent on both its self-assembly into a canonical “Z-ring” and interaction with protein binding partners, which results in the activation of enzymes that remodel the cell wall to drive constriction. Using mutants of FtsZ and its binding partners, we have established the role of its C-terminal linker domain in regulating Z-ring organization, as well as the requirement for its C-terminal conserved peptide and interaction with the membrane-anchoring protein FtsA for regulating cell wall remodeling for constriction.
Differentiated Cournot duopoly game with fractional-order and its discretization
Authors: Al-khedhairi A.
Published: May 2019

Purpose

Fractional calculus provides powerful tool to build more realistic and accurate mathematical models in economic field. This paper aims to explore a proposed fractional-order differentiated Cournot duopoly game and its discretized game.

Design/methodology/approach

Conditions for existence and uniqueness of the proposed game’s solution are derived. The existence of Nash equilibrium point and its local and global stability are obtained. Furthermore, local stability analysis of the discretized game is investigated. The effects of fractional-order on game’s dynamics are examined, along with other parameters of the game, via the 2D bifurcation diagrams in planes of system’s parameters are acquired.

Findings

Theoretical and numerical simulation results demonstrate rich variety of interesting dynamical behaviors such as period-doubling and Neimark–Sacker bifurcations, attractors’ crises in addition to chaotic attractors. The results demonstrated that the stability Nash equilibrium point of the game can be lost by period doubling or Neimark–Sacker bifurcations.

Practical implications

Oligopoly games are pivotal in the mathematical modeling of some substantial economic areas such as industrial organization, airline, banking, telecommunication companies, international trade and also macroeconomic analysis of business cycles, innovation and growth.

Originality/value

Although the Cournot game and its variants have attracted great interest among mathematicians and economists since the time of its proposition till present, memory effects in continuous-time and discrete-time Cournot duopoly game have not been addressed yet. To the best of author’s knowledge, this can be considered as the first attempt to investigate this problem of fractional-order differentiated Cournot duopoly game. In addition, studying more realistic models of Cournot oligopoly games plays a pivotal role in the mathematical investigation and better understanding of some substantial economic areas such as industrial organization, airline, banking, telecommunication companies, international trade and also in macroeconomic analysis of business cycles, innovation and growth.
Crime and social media
Authors: Asongu Simplice , Nwachukwu Jacinta , Orim Stella-Maris , Pyke Chris
Published: May 2019

Purpose

The purpose of this paper is to complement the scant macroeconomic literature on the development outcomes of social media by examining the relationship between Facebook penetration and violent crime levels in a cross-section of 148 countries for the year 2012.

Design/methodology/approach

The empirical evidence is based on ordinary least squares (OLS), Tobit and quantile regressions. In order to respond to policy concerns on the limited evidence on the consequences of social media in developing countries, the data set is disaggregated into regions and income levels. The decomposition by income levels included: low income, lower middle income, upper middle income and high income. The corresponding regions include: Europe and Central Asia, East Asia and the Pacific, Middle East and North Africa (MENA), Sub-Saharan Africa and Latin America.

Findings

From OLS and Tobit regressions, there is a negative relationship between Facebook penetration and crime. However, quantile regressions reveal that the established negative relationship is noticeable exclusively in the 90th crime quantile. Further, when the data set is decomposed into regions and income levels, the negative relationship is evident in the MENA while a positive relationship is confirmed for Sub-Saharan Africa. Policy implications are discussed.

Originality/value

Studies on the development outcomes of social media are sparse because of a lack of reliable macroeconomic data on social media. This study primarily complemented three existing studies that have leveraged on a newly available data set on Facebook.
How does business-IT strategic alignment dimension impact on organizational performance measures
Authors: Ilmudeen Aboobucker , Bao Yukun , Alharbi Ibraheem Mubarak
Published: May 2019

Purpose

Despite the conceptual, empirical and theoretical advances in alignment–performance relationship, there is a limited research on the alignment dimensions and organizational performance measures. Though strategic alignment is believed to improve organizational performance, the purpose of this paper is to develop conjectures for understanding how different alignment dimensions influence organizational performance measures.

Design/methodology/approach

The data were acquired from 161 senior IT and business managers paired responses in China and were analyzed by using a structural equation modeling technique.

Findings

The hypothesized relationships are largely supported. Thus, quality-oriented strategic alignment dimension has a significant relationship with all performance measures. Contrary to expectations, both product and marketing-oriented strategic alignment dimensions do not show a significant impact on financial return. The marketing-oriented strategic alignment dimension also has an insignificant relationship with operational excellence.

Practical implications

This study suggests that the business–IT alignment can be dimensioned to better combine business strategy and IT strategy. Hence, managers can focus specific alignment dimension instead of entire strategies of a firm for a better decision making.

Originality/value

Findings suggest guidance for formulating combined business and IT strategic alignment into dimensions and proposing insightful and practical implications.
Factors influencing consumers’ adoption of Islamic mobile banking services in Malaysia
Authors: Mohd Thas Thaker Mohamed Asmy Bin , Allah Pitchay Anwar Bin , Mohd Thas Thaker Hassanudin Bin , Amin Md Fouad Bin
Published: May 2019

Purpose

This paper aims to test the factors that can influence the adoption of Islamic mobile banking services among the current users in Malaysia.

Design/methodology/approach

A sample of 250 current users of Islamic mobile banking services provided opinions about their intention to adopt Islamic mobile banking services. Later, the data are analysed using partial least squares approach.

Findings

Perceived usefulness and risk are the factors that influence the intention to adopt Islamic mobile banking services among the existing users.

Research limitations/implications

There are some limitations of the current study. The sample size and area of study becomes the obvious limitations. Thus, there is a need for caution in the interpretation of the results and the conclusion cannot be as generalised. Besides, the use of current factors might limit the ability to explore other potentially important determinants of the users. Thus, future research can be conducted by incorporating new factors and provide new insights for Islamic mobile banking services. In addition, the sample is biased towards people who are currently using mobile banking services.

Practical implications

By understanding these factors among the customers, it would help the industry player, particularly Islamic financial institutions to plan and strategise appropriate policies and support necessary programme on diversifying and promoting financial transaction using mobile banking services among their existing and potential customers.

Originality/value

This paper offers an additional literature on Islamic mobile banking, especially from the Malaysian context. There is a lack of study that focusses on Islamic mobile banking services. The paper is considered to be the first attempt to examine factors that influence Malaysian Islamic banking customers to adopt Islamic mobile banking services, which is not often considered in previous studies.
Contingent use of rational, intuitive and political decision-making in R&D
Authors: Kolbe Linn Marie , Bossink Bart , de Man Ard-Pieter
Published: May 2019

Purpose

The purpose of this paper is to gain insight into the contingent use of rational, intuitive and political decision-making in R&D.

Design/methodology/approach

This research is based on a study in an R&D department of a multinational high-tech firm in the Netherlands. The study consists of a case study design, focusing on four embedded cases, longitudinally studying each case.

Findings

The literature distinguishes three dimensions of innovation decision-making processes: rational, intuitive and political. By studying these interwoven dimensions over time, this study finds that the dominant use of each of these dimensions differs across the innovation process. There is an emphasis on intuitive decision-making in an early phase, followed by more emphasis on political decision-making, and moving to more emphasis on rational decision-making in a later phase of the R&D process. Furthermore, the predominant choice in a specific innovation phase for one of the three decision-making dimensions is influenced by the decision-making dimension that is dominantly employed in the preceding phase.

Research limitations/implications

This study contributes to the innovation decision-making literature by developing and applying a model that distinguishes rational, intuitive and political decision-making dimensions, the interactions among these dimensions in innovation decision-making in R&D, and the contingency of these dimensions upon the innovation phase. It calls for further research into the contingent nature of innovation decision-making processes.

Practical implications

For practitioners this study has two relevant insights. First it highlights the importance and usefulness of intuitive and political decision-making in addition to the prevailing emphasis on rational decision-making. Second, practitioners may be more alert to consciously changing their dominant decision-making approach across the phases of the innovation process. Third, companies may adjust their human resource policies to this study’s findings.

Originality/value

The literature on rational, intuitive and political decision-making is quite extensive. However, research has hardly studied how these decision-making dimensions develop in conjunction, and over time. This paper reports on a first study to do so and finds that the dominant use of these dimensions is contingent upon the phase of the R&D process and on the decision-making dimensions used in earlier phases. The study suggests that using a contingency approach can help to further integrate the debate in research and practice.
Lean Six Sigma in healthcare
Authors: Improta Giovanni , Balato Giovanni , Ricciardi Carlo , Russo Mario Alessandro , Santalucia Ida , Triassi Maria , Cesarelli Mario
Published: May 2019

Purpose

Since healthcare spending accounts for approximately 6.6 per cent of the gross domestic product, reducing waste in health facilities is necessary to generate significant cost savings. After previous work concerning the application of Lean Six Sigma (LSS) to hip surgery, the purpose of this paper is to use LSS as the correct methodology to analyse a clinical pathway. Fast track surgery was introduced to the Complex Operative Unit of Orthopaedic and Traumatology of the University Hospital “Federico II” to improve quality and further reduce costs associated with prosthetic hip replacement surgery.

Design/methodology/approach

The DMAIC (Define, measure, analyse, improve, control) roadmap was used as the typical problem-solving approach of the LSS methodology. A rigorous process of defining, measuring, analysing, improving and controlling business problems can be used to reach fixed goals. The paper was written following the Standards for Quality Improvement Reporting Excellence (SQUIRES Guidelines).

Findings

In this work, the authors found that multiple variables could influence the length of hospital stay (LOS) for inpatient treatment, thereby increasing patient management costs due to longer periods of hospitalisation. Therefore, LSS analysis of the implemented corrective actions demonstrated the efficacy and efficiency of the novel protocol. The average LOS was reduced from 10.66 to 7.8 days (−26.8 per cent).

Originality/value

The introduction of fast track surgery was validated through a rigorous LSS analysis, which demonstrated that the new protocol benefitted both patients and the hospital.
Modeling Price Volatility Based on a Genetic Programming Approach
Authors: Ding Shusheng , Zhang Yongmin , Duygun Meryem
Published: May 2019

Business profitability is highly dependent on risk management strategies to hedge future cash flow uncertainty. Commodity price shocks and fluctuations are key risks for companies with global supply chains. The purpose of this paper is to show how artificial intelligence (AI) techniques can be used to model the volatility of commodity prices. More specifically, the authors introduce a new model – LIQ‐GARCH – that uses genetic programming to forecast volatility. The newly generated model is then used to forecast the volatility of the following three indexes: the Commodity Research Bureau (CRB) index, the West Texas Intermediate (WTI) oil futures prices and the Baltic Dry Index (BDI). The empirical model performance tests show that the newly generated model in this paper is considerably more accurate than the traditional GARCH model. As a result, this model can help businesses to design optimal risk management strategies and to hedge themselves against price uncertainty.
The effects of populism as a social identity frame on persuasion and mobilisation: Evidence from a 15‐country experiment
Authors: BOS LINDA , SCHEMER CHRISTIAN , CORBU NICOLETA , HAMELEERS MICHAEL , ANDREADIS IOANNIS , SCHULZ ANNE , SCHMUCK DESIRÉE , REINEMANN CARSTEN , FAWZI NAYLA
Published: May 2019

This article investigates the impact of populist messages on issue agreement and readiness for action in 15 countries (N = 7,286). Specifically, populist communicators rely on persuasive strategies by which social group cues become more salient and affect people's judgment of and political engagement with political issues. This strategy is called ‘populist identity framing’ because the ordinary people as the in‐group is portrayed as being threatened by various out‐groups. By blaming political elites for societal or economic problems harming ordinary people, populist communicators engage in anti‐elitist identity framing. Another strategy is to blame immigrants for social problems – that is, exclusionist identity framing. Finally, right‐wing political actors combine both cues and depict an even more threatening situation of the ordinary people as the in‐group. Based on social identity theory, an experimental study in 15 European countries shows that most notably the anti‐elitist identity frame has the potential to persuade voters. Additionally, relative deprivation makes recipients more susceptible to the mobilising impact of the populist identity frames.
Complex Coacervation Between Gelatin and Chia Mucilage as an Alternative of Encapsulating Agents
Authors: Hernández‐Nava Ruth , López‐Malo Aurelio , Palou Enrique , Ramírez‐Corona Nelly , Jiménez‐Munguía María Teresa
Published: May 2019

Complex coacervation between gelatin type B (GE) and chia mucilage (ChM) was studied. GE‐ChM were mixed at mass ratios of 1:1, 2:1, 3:1, 4:1, and 1:2 in a pH range of 1.50 to 5.00, maintaining a total solid concentration of 0.2% (w/w), using turbidity and viscosity tests to obtain the highest yield of complex coacervates. To characterize the complex coacervates, morphology and Fourier‐transform infrared spectroscopy (FTIR) were determined. The optimum yield for complex coacervation was achieved with a GE‐ChM mass ratio of 2:1 and pH value of 3.6. The critical pH values associated with the formation of soluble (pHc) and insoluble (pHɸ1) complexes, and complete dissociation (pHɸ2) at the optimum GE‐ChM ratio were found to be 4.50, 4.10, and 2.00, respectively. It was observed that increasing the mass ratio of GE or ChM, the yield of complex coacervates decreased; the higher yields were obtained with the proportions of 2:1 and 1:1 with values of 68.25 ± 0.05% and 61.04 ± 0.05%, respectively. Capsules formed at mass ratios of 1:1, 2:1, and 3:1, had the characteristic grape agglomerate shape for complex coacervates. Further characterization with scanning electron microscopy (SEM) showed a spherical shape for capsules. FTIR spectrum of complex coacervates at optimum conditions had a combination of bands corresponding to GE and ChM, suggesting an interaction between GE‐ChM during the formation of complex coacervates. Therefore, complex coacervates between GE‐ChM can be formed, and could be used as an alternative as encapsulating agents to be applied in the food industry.

Practical Application

Complex coacervation is a technique that is being studied in several applications in the food industry. However, studies are still being made to explore different possibilities of natural sources to be used in complex coacervation. This study showed that the combination of gelatin and chia mucilage may be an alternative as encapsulating agents for complex coacervation to be applied in the food industry.
Price of Four Loko in Large U.S. Cities, 2018
Authors: Rossheim Matthew E. , Thombs Dennis L. , Treffers Ryan D. , Trangenstein Pamela J. , McDonald Kayla K. , Ahmad Reema , Siklo Sieka S. , Gonzalez‐Pons Kwynn M. , Suzuki Sumihiro , Jernigan David H.
Published: May 2019

Background

Supersized alcopops are flavored alcoholic beverages that contain up to 5.5 standard alcoholic drinks in a single can. Limited research suggests Four Loko—the most commonly consumed supersized alcopop by underage drinkers—is among the least expensive ready‐to‐drink alcohol products on the U.S. market. This is a public health concern because alcohol prices are inversely associated with consumption and related harms, particularly among youth. This study investigated Four Loko's retail price per volume of alcohol in large U.S. cities.

Methods

This study used multistage random sampling to collect data in the largest city of each state and Washington, DC. A simple random sample of 5 ZIP codes from each city was selected and entered into Four Loko's website product locator. Within ZIP codes, up to 4 stores were randomly selected and contacted by telephone. Retailers were interviewed about Four Loko in regard to: availability, volume, alcohol by volume (abv), price for 1 can, and discounts for purchasing more than 1 can.

Results

The sample included 344 retail stores with Four Loko in stock. Average price per standard alcoholic drink (i.e., 14 g of absolute alcohol) was $0.54 for Four Loko products. Taking into account volume, price, and discounts, an average of 17 standard alcoholic drinks could be purchased via Four Loko with $10. Adjusted analysis using linear regression showed that availability of bulk price discounts and higher abv (14% vs. 12%) were associated with lower price per drink.

Conclusion

This study verifies that Four Loko is among the least expensive ready‐to‐drink alcohol available for purchase in the United States. Given that consuming a single supersized alcopop constitutes binge drinking and is therefore unsafe, regulatory agencies should consider a variety of steps to reduce the availability and abv of these products and increase their retail price in order to reduce and prevent unsafe alcohol consumption.
The effects of sodium hypochlorite and ethylenediaminetetraacetic acid on the microhardness of Mineral Trioxide Aggregate and TotalFill Bioceramic Putty
Authors: Chu Jacklyn H.R. , Chia Kalie Y. , Qui Alexander L. , Moule Alex , Ha William N.
Published: May 2019

This study aimed to evaluate the effects of 5% NaOCl and 17% EDTA on the Vickers microhardness of Mineral Trioxide Aggregate, MTA Angelus (MTAA), and TotalFill Bioceramic Putty (BCP) after 24 h and 8 days. Twenty‐four samples of MTAA and BCP were tested for baseline microhardness at 24 h. They were divided into four subgroups (5% NaOCl or 17% EDTA, 24 h, 5% NaOCl or 17% EDTA at 8 days) and microhardness was evaluated at different time‐points. Results were recorded and analysed statistically via one‐way anova Kruskal–Wallis test and post hoc uncorrected Dunn's multiple comparison test. MTAA had a higher baseline microhardness than BCP. NaOCl reduced the microhardness of MTAA but increased that of BCP. EDTA reduced the microhardness for both materials at 24 h. At 8 days, EDTA reduced the microhardness of MTAA, while BCP exhibited an increase in microhardness. Enabling these materials to set for a week prior to exposure to irrigants improves their microhardness.
A Lady’s Bicycle
Authors: Bundgaard Helle
Published: May 2019

This story concerns ethical dilemmas related to unintended consequences of fieldwork. The setting in a small Indian village works as a prism that offers an opportunity to reflect upon our practice as anthropologists. One of the challenges of fieldwork in a setting with relatively little material wealth is that objects that to the anthropologist are simply a matter of convenience represent resources otherwise out of reach and might lead to competition among interlocutors and power struggles. The bicycle thus articulates the unequal relation between anthropologist and interlocutors.
Why This Killer Should Live
Authors: Cheng Jesse
Published: May 2019

This piece is a reproduction of a legal memorandum that I wrote as an engaged ethnographer working on the legal team of a capitally charged criminal defendant in the United States. I present it as an example of my attempts during fieldwork to bring some anthropologically inflected inspiration to the humanizing endeavors of capital defense advocacy.