bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatiotemporal refinement of signal flow through association cortex during learning
Authors: Gilad Ariel , Helmchen Fritjof
Published: August 2019

Association areas in neocortex encode novel stimulus-outcome relationships but the principles of their engagement during task learning remain elusive. Using chronic wide-field calcium imaging we reveal two phases of spatiotemporal refinement of layer 2/3 cortical activity in mice learning whisker-based texture discrimination. Even before mice reach learning threshold, association cortex—including rostro-lateral (RL), posteromedial (PM), and retrosplenial dorsal (RD) areas—is generally suppressed early during trials (between auditory start cue and whisker-texture touch). As learning proceeds, a spatiotemporal activation sequence builds up, spreading from auditory areas to RL immediately before texture touch (whereas PM and RD remain suppressed) and continuing into barrel cortex, which eventually efficiently discriminates between textures. Additional correlation analysis substantiates this diverging learning-related refinement within association cortex. Our results indicate that a pre-learning phase of general suppression in association cortex precedes a learning-related phase of task-specific signal flow enhancement.
Structural basis of reiterative transcription from the pyrG and pyrBI promoters by bacterial RNA polymerase
Authors: Shin Yeonoh , Hedglin Mark , Murakami Katsuhiko S.
Published: August 2019

Reiterative transcription is a non-canonical form of RNA synthesis by RNA polymerase in which a ribonucleotide specified by a single base in the DNA template is repetitively added to the nascent RNA transcript. We previously determined the X-ray crystal structure of the bacterial RNA polymerase engaged in reiterative transcription from the pyrG promoter, which contains 8 poly-G RNA bases synthesized using 3 C bases in the DNA as a template and extends RNA without displacement of the promoter recognition σ factor from the core enzyme. In this study, we determined a series of transcript initiation complex structures from the pyrG promoter using soak trigger freeze X-ray crystallography. We also performed biochemical assays to monitor template DNA translocation during RNA synthesis from the pyrG promoter and in vitro transcription assays to determine the length of poly-G RNA from the pyrG promoter variants. Structures and biochemical assays revealed how the RNA transcript from the pyrG promoter is guided toward the Rifampin-binding pocket then the main channel of RNA polymerase and provided insight into RNA slippage during reiterative transcription of the pyrG promoter. Lastly, we determined a structure of a reiterative transcription complex at the pyrBI promoter and revealed an alternative mechanism of RNA slippage and extension requiring the σ dissociation from the core enzyme.

SIGNIFICANCE STATEMENT

RNA polymerase synthesizes multiple bases of RNA using a single base of the template DNA due to slippage between RNA transcript and template DNA. This noncanonical RNA synthesis is called “reiterative transcription,” playing several regulatory roles cellular organisms and viruses. In this study, we determined a series of X-ray crystal structures of a bacterial RNA polymerase engaged in reiterative transcription and characterized a role of template DNA during reiterative transcription by biochemical assays. Our study revealed how RNA slips on template DNA and how RNA polymerase and template DNA determine length of reiterative RNA product. We also provide insights into the regulation of gene expression using two alternative ways of reiterative transcription.
Developing T cells form an immunological synapse for passage through the β−selection checkpoint
Authors: Allam Amr H. , Charnley Mirren , Pham Kim , Russell Sarah M.
Published: August 2019

The β-selection checkpoint of T cell development tests whether the cell has recombined its genomic DNA to produce a functional T Cell Receptor β (TCRβ) receptor. Passage through the β-selection checkpoint requires the nascent TCRβ protein to mediate signaling through a pre-TCR complex. In this study, we show that developing T cells at the β-selection checkpoint establish an immunological synapse in in vitro & in situ, resembling that of the mature T cell. The immunological synapse is dependent on two key signaling pathways known to be critical for the transition beyond the β-selection checkpoint, Notch and CXCR4 signaling. In vitro and in situ analyses indicate that the immunological synapse promotes passage through the β-selection checkpoint. Collectively, these data indicate that developing T cells regulate pre-TCR signaling through the formation of an immunological synapse. This signaling platform integrates cues from Notch, CXCR4, and MHC on the thymic stromal cell, to allow transition beyond the β-selection checkpoint.

T cell development requires testing whether genomic rearrangement has produced a T cell receptor capable of transmitting signals. Most T cells fail this test. Here, we show that passage through the β-selection checkpoint requires assembly of a platform to support TCR signaling.
The role of dopaminergic nuclei in predicting and experiencing gains and losses: A 7T human fMRI study
Authors: Fontanesi Laura , Gluth Sebastian , Rieskamp Jörg , Forstmann Birte U.
Published: August 2019

The ability to predict the outcomes of actions based on experience is crucial for making successful decisions in new or dynamic environments. In animal studies using electrophysiology, it was found that dopamine neurons, located in the substantia nigra (SN) and the ventral tegmental area (VTA), have a crucial role in feedback-based learning. However, human neuroimaging studies have provided inconclusive results. The present work used ultrahigh field (7 Tesla) structural and functional MRI and optimized protocols to extract SN and VTA signals in human participants. In a number-guessing task, we found significant correlations with reward prediction error and risk in both the SN and the VTA and no correlation with expected value. We also found a surprise signal in the SN. These results are in line with a recent framework that proposed a differential role for the VTA and the SN in, respectively, learning of values and surprise.
Intersecting vulnerabilities: Climatic and demographic contributions to future population exposure to Aedes-borne viruses in the United States
Authors: Rohat Guillaume , Monaghan Andrew , Hayden Mary H. , Ryan Sadie J. , Wilhelmi Olga
Published: August 2019

Understanding how climate change and demographic factors may shape future population exposure to viruses such as Zika, dengue, or chikungunya, transmitted by Aedes mosquitoes is essential to improving public health preparedness. In this study, we combine projections of cumulative monthly Aedes-borne virus transmission risk with spatially explicit population projections for vulnerable demographic groups (age and economic factors) to explore future county-level population exposure across the conterminous United States. We employ a scenario matrix – combinations of climate and socioeconomic scenarios (Representative Concentration Pathways and Shared Socioeconomic Pathways) – to assess the full range of uncertainty in emissions, socioeconomic development, and demographic change. Human exposure is projected to increase under most scenarios, up to +177% at the national scale in 2080 relative to 2010. Projected exposure changes are predominantly driven by population changes in vulnerable demographic groups, although climate change is also important, particularly in the western region where future exposure may decrease by >30% under the strongest climate change mitigation scenario. The results emphasize the crucial role that socioeconomic and demographic change play in shaping future population vulnerability and exposure to Aedes-borne virus transmission risk in the United States, and underscore the importance of including socioeconomic scenarios in projections of climate-related vector-borne disease impacts.
Decoding sounds depicting hand-object interactions in primary somatosensory cortex
Authors: Bailey Kerri M , Giordano Bruno L , Kaas Amanda L , Smith Fraser W
Published: August 2019

Neurons, even in earliest sensory regions of cortex, are subject to a great deal of contextual influences from both within and across modality connections. Recent work has shown that primary sensory areas can respond to and in some cases discriminate stimuli not of their target modality: for example, primary somatosensory cortex (SI) discriminates visual images of graspable objects. In the present work, we investigated whether SI would discriminate sounds depicting hand-object interactions (e.g. bouncing a ball). In a rapid event-related functional magnetic resonance imaging (fMRI) experiment, participants listened attentively to sounds from three categories: hand-object interactions, and control categories of pure tones and animal vocalizations, while performing a one-back repetition detection task. Multi-voxel pattern analysis revealed significant decoding of different hand-object interactions within SI, but not for either control category. Crucially, in the hand-sensitive voxels defined from an independent tactile localizer, decoding accuracies were significantly higher for hand-object interactions compared to pure tones in left SI. Our findings indicate that simply hearing sounds depicting familiar hand-object interactions elicit different patterns of activity in SI, despite the complete absence of tactile stimulation. These results highlight the rich information that can be transmitted across sensory modalities even to primary sensory areas.
CHD8 regulates the balance between proliferation and differentiation of human iPSCs in neural development
Authors: Liu Wenzhong , Dong Weilai , Hoffman Ellen J. , Fernandez Thomas V. , Gupta Abha R.
Published: August 2019

Background

Chromodomain helicase DNA-binding protein 8 (CHD8), which encodes a chromatin remodeling protein that regulates Wnt/β-catenin mediated gene expression, is one of the most strongly associated genes with autism spectrum disorder (ASD). Characterization of ASD patients with CHD8 disrupting mutations and animal and stem cell models of CHD8 deficiency suggest that CHD8 plays a role in neurodevelopment.

Methods

We generated iPSCs from the T-lymphocytes of a healthy, typically-developing human male and iPSC lines from the same source which were subjected to CRISPR/Cas9-mediated knockdown (KD) of CHD8. We subsequently derived neural progenitor cells (NPCs) and neural cells and examined the effects of CHD8 deficiency on cell proliferation and neural differentiation.

Results

We observed that, compared to WT, CHD8 KD: (1) increased the number of iPSC colonies formed, (2) suppressed spontaneous differentiation along the edges of iPSC colonies, (3) increased the proliferation of NPCs, (4) delayed the formation of neural rosettes, (5) delayed neurite outgrowth, (6) decreased the percentage of cells in the G0/G1 phase of the cell cycle, (7) increased the percentage of cells in the G2/M phase of the cell cycle, (8) decreased presence of the neuronal marker MAP2 although not the glial marker GFAP, (9) decreased presence for the excitatory neuronal marker VGLUT1, and (10) decreased presence of the synaptic marker SYN1.

Conclusions

Our results suggest that CHD8 deficiency causes alterations in the cell cycle. More specifically, CHD8 KD appears to increase cell proliferation and delay neural differentiation. This may contribute to the pathophysiology of ASD.
Theta power and theta-gamma coupling support spatial memory retrieval
Authors: Vivekananda Umesh , Bush Daniel , Bisby James A , Baxendale Sallie , Rodionov Roman , Diehl Beate , Chowdhury Fahmida A , McEvoy Andrew W , Miserocchi Anna , Walker Matthew C , Burgess Neil
Published: August 2019

Hippocampal theta oscillations have been implicated in spatial memory function in both rodents and humans. What is less clear is how hippocampal theta interacts with higher frequency oscillations during spatial memory function, and how this relates to subsequent behaviour. Here we asked ten human epilepsy patients undergoing intracranial EEG recording to perform a desk-top virtual reality spatial memory task, and found that increased theta power in two discrete bands (‘low’ 2-5Hz and ‘high’ 6-9Hz) during cued retrieval was associated with improved task performance. Similarly, increased coupling between ‘low’ theta phase and gamma amplitude during the same period was associated with improved task performance. These results support a role of theta oscillations and theta-gamma phase-amplitude coupling in human spatial memory function.
Molecular signatures for inflammation vary across cancer types and correlate significantly with tumor stage, gender and vital status of patients
Authors: So Alexandra R. , Si Jeong Min , Lopez David , Pellegrini Matteo
Published: August 2019

Cancer affects millions of individuals worldwide. One shortcoming of traditional cancer classification systems is that, even for tumors affecting a single organ, there is significant molecular heterogeneity. Precise molecular classification of tumors could be beneficial in personalizing patients’ therapy and predicting prognosis. To this end, here we propose to use molecular signatures to further refine cancer classification. Molecular signatures are collections of genes characterizing particular cell types, tissues or disease. Signatures can be used to interpret expression profiles from heterogeneous samples. Large collections of gene signatures have previously been cataloged in the MSigDB database. We have developed a web-based Signature Visualization Tool (SaVanT) to display signature scores in user-generated expression data. Here we have undertaken a systematic analysis of correlations between inflammatory signatures and cancer samples, to test whether inflammation can differentiate cancer types. Inflammatory response signatures were obtained from MsigDB and SaVanT and a signature score was computed for samples associated with 7 different cancer types. We first identified types of cancers that had high inflammation levels as measured by these signatures. The correlation between signature scores and metadata of these patients (gender, age at initial cancer diagnosis, cancer stage, and vital status) was then computed. We sought to evaluate correlations between inflammation with other clinical parameters and identified four cancer types that had statistically significant association (p-value < 0.05) with at least one clinical characteristic: pancreas adenocarcinoma (PAAD), cholangiocarcinoma (CHOL), kidney chromophobe (KICH), and uveal melanoma (UVM). These results may allow future studies to use these approaches to further refine cancer subtyping and ultimately treatment.
A mechanistic view of collective filament motion in active nematic networks
Authors: Striebel Moritz , Graf Isabella R. , Frey Erwin
Published: August 2019

Protein filament networks are structures crucial for force generation and cell shape. A central open question is how collective filament dynamics emerges from interactions between individual network constituents. To address this question we study a minimal but generic model for a nematic network where filament sliding is driven by the action of motor proteins. Our theoretical analysis shows how the interplay between viscous drag on filaments and motor-induced forces governs force propagation through such interconnected filament networks. We find that the ratio between these antagonistic forces establishes the range of filament interaction, which determines how the local filament velocity depends on the polarity of the surrounding network. This force propagation mechanism implies that the polarity-independent sliding observed in Xenopus egg extracts, and in-vitro experiments with purified components, is a consequence of a large force propagation length. We suggest how our predictions can be tested by tangible in vitro experiments whose feasibility is assessed with the help of simulations and an accompanying theoretical analysis.
The BUBR1 pseudokinase domain promotes efficient kinetochore PP2A-B56 recruitment to regulate spindle checkpoint silencing and chromosome alignment
Authors: Braga Luciano Gama , Cisneros Angel F. , Mathieu Michelle , Clerc Maxime , Garcia Pauline , Lottin Baptiste , Garand Chantal , Thebault Philippe , Landry Christian R , Elowe Sabine
Published: August 2019

The balance of phospho-signalling at outer-kinetochores during mitosis is critical for the accurate attachments between kinetochores and the mitotic spindle and timely exit from mitosis. In humans, a major player in determining this balance is the PP2A-B56 phosphatase which is recruited to the Kinase Attachment Regulatory Domain (KARD) of the Spindle Assembly Checkpoint protein Budding Uninhibited by Benzimidazole 1-related 1 (BUBR1) in a phospho-dependent manner. This event unleashes a rapid, switch-like phosphatase relay that reverses phosphorylation at the kinetochore, extinguishing the checkpoint and promoting anaphase entry. Here, we conclusively demonstrate that the pseudokinase domain of human BUBR1 lacks phosphotransfer activity and that it was maintained in vertebrates because it allosterically promotes KARD phosphorylation. Mutation or removal of this domain results in decreased PP2A-B56 recruitment to the outer kinetochore, attenuated checkpoint silencing and errors in chromosome alignment as a result of imbalance in Aurora B activity. We demonstrate that the functions of the BUBR1 pseudokinase and the BUB1 kinase domains are intertwined, providing an explanation for retention of the pseudokinase domain in certain eukaryotes.
Direct comparison of clathrin-mediated endocytosis in budding and fission yeast reveals conserved and evolvable features
Authors: Sun Yidi , Schoeneberg Johnannes , Chen Shirley , Jiang Tommy , Kaplan Charlotte , Xu Ke , Pollard Thomas D. , Drubin David G.
Published: August 2019

Abstract

Conserved proteins drive clathrin-mediated endocytosis (CME), which universally involves a burst of actin assembly. To gain fundamental mechanistic insights into this process, a side-by-side quantitative comparison of CME was performed on two distantly related yeast species. Though endocytic protein abundance in S. pombe and S. cerevisiae are more similar than previously thought, membrane invagination speed and depth are two-fold greater in fission yeast than in budding yeast. In both yeasts, Arp2/3 complex activation drives membrane invagination when triggered by the accumulation of ∼70 WASP molecules. In contrast to budding yeast, WASP-mediated actin nucleation activity plays an essential role in fission yeast endocytosis. Genetics and live-cell imaging revealed core CME spatiodynamic similarities between the two yeasts, though two-zone actin assembly is a fission yeast-specific mechanism, which is not essential for CME. These studies identified conserved CME mechanisms and species-specific adaptations and have broad implications that extend from yeast to humans.
Melt electrowritten scaffolds with bone-inspired fibrous and mineral architectures to enhance BMP2 delivery and human MSC osteogenesis
Authors: Eichholz Kian F. , Hoey David A.
Published: August 2019

1

Material micro-architecture and chemistry play pivotal roles in driving cell behaviour. Bone at a cellular level consists of arranged fibres with a cross-fibrillar mineral phase made up of curved nano-sized needle shaped crystals. This nano-structured mineral architecture can bind and stabilise proteins within bone for centuries and thus holds promise as a strategy for therapeutic delivery in regenerative medicine. Herein, we use melt electrowriting (MEW) technology to create fibrous 3D PCL micro-architectures. These scaffolds were further modified with an extrafibrillar coating of plate shaped micron-sized calcium phosphate crystals (pHA), or with a novel extrafibrillar coating of needle shaped nano-sized crystals (nnHA). A third scaffold was developed whereby nano-sized crystals were placed intrafibrillarly during the MEW process (iHA). X-ray diffraction revealed altered crystal structure and crystallinity between groups, with hydroxyapatite (HA) being the primary phase in all modifications. Water contact angle was investigated revealing increased hydrophilicity with extrafibrillar coatings, while tensile testing revealed enhanced stiffness in scaffolds fabricated with intrafibrillar HA. Biological characterisation demonstrated significantly enhanced human stem/stromal cell mineralisation with extrafibrillar coatings, with a 5-fold increase in mineral deposition with plate like structures and a 14-fold increase with a needle topography, demonstrating the importance of bone mimetic architectures. Given the protein stabilising properties of mineral, these materials were further functionalised with BMP2. Extrafibrillar coatings of nano-needles facilitated a controlled release of BMP2 from the scaffold which further enhanced mineral deposition by osteoprogenitors. This study thus outlines a method for fabricating scaffolds with precise fibrous micro-architectures and bone mimetic nano-needle HA extrafibrillar coatings which significantly enhance mesenchymal stem/stromal cell (MSC) osteogenesis and therapeutic delivery and thus hold great promise for bone tissue regeneration.
Local embeddedness, corporate social capital and Chinese enterprises
Authors: Bian Yanjie , Xie Juan , Yang Yang , Hao Mingsong
Published: August 2019

Purpose

The purpose of this study is to examine the impact of corporate social capital and local embeddedness on perceived business performance of Chinese enterprises operating overseas, whose recent growth resulted from the Belt and Road Initiative.

Design/methodology/approach

This study reports the results of a sample of 83 Shaanxi outward foreign direct investment (FDI) firms operating in Africa, Asia, Australia, Europe and North America. In-depth interviews with a few sampled firms are used to develop the survey questionnaire and help interpret the results of statistical analysis.

Findings

This study proposes two hypotheses and both are supported by the data. First, corporate social capital is a three-dimensional concept, covering governmental, market and personal sources with each source making an equal, positive effect on perceived overseas performance of the surveyed firms. Second, these firms do better when having developed a higher degree of local embeddedness, a measure on local channels used to obtain information and mobilize resources. While local embeddedness indeed mediates some effect of corporate social capital, both variables have shown direct impact on performance.

Research limitations/implications

Reported findings are from a small sample of 83 firms in an inland Chinese province, and business performance is measured by subjective evaluation rather than economic output.

Practical implications

The practical implication is that a Chinese FDI firm is expected to maintain all three relational channels – governmental, market and interpersonal – because the firm can gain different kinds of information and resources from these sources and each channel is necessary and equally important for the firm’s development. Importantly, it needs a different strategy to maintain and best use each channel. For the Belt and Road Initiative to be effective, China must establish platforms through which enterprises can strengthen and reconfigure their corporate social capital, as well as to cultivate and sustain their local networks in foreign destinations.
Self-reflection and employee creativity
Authors: Wang Zhining , Liu Dandan , Cai Shaohan
Published: August 2019

Purpose

This paper aims to examine the effect of self-reflection on employee creativity in China. The authors identify individual intellectual capital (IIC) as a mediator and concerns for face as a moderator for this relationship.

Design/methodology/approach

A sample of 351 dyads of full-time employees and their immediate supervisors from various Chinese companies were surveyed. Regression analysis and structural equation modeling were used to test the research model.

Findings

Three dimensions of self-reflection significantly affect IIC and subsequently lead to employee creativity; IIC mediates the relationship between three dimensions of self-reflection and employee creativity; concern for face negatively moderates the effect of IIC on employee creativity.

Practical implications

Managers can facilitate employees’ creativity by motivating them to conduct self-reflection and develop IIC, and by nurturing a safe atmosphere that allows individuals to take risks without losing face.

Originality/value

This is one of the first empirical studies to investigate the mediating effects of IIC and the moderating effects of concerns for face on the relationship between self-reflection and creativity.
Rendering optimal design under various uncertainties
Authors: Lü Hui , Yang Kun , Shangguan Wen-bin , Yin Hui , Yu DJ
Published: August 2019

Purpose

The purpose of this paper is to propose a unified optimization design method and apply it to handle the brake squeal instability involving various uncertainties in a unified framework.

Design/methodology/approach

Fuzzy random variables are taken as equivalent variables of conventional uncertain variables, and a unified response analysis method is first derived based on level-cut technique, Taylor expansion and central difference scheme. Next, a unified reliability analysis method is developed by integrating the unified response analysis and fuzzy possibility theory. Finally, based on the unified reliability analysis method, a unified reliability-based optimization model is established, which is capable of optimizing uncertain responses in a unified way for different uncertainty cases.

Findings

The proposed method is extended to perform squeal instability analysis and optimization involving various uncertainties. Numerical examples under eight uncertainty cases are provided and the results demonstrate the effectiveness of the proposed method.

Originality/value

Most of the existing methods of uncertainty analysis and optimization are merely effective in tackling one uncertainty case. The proposed method is able to handle the uncertain problems involving various types of uncertainties in a unified way.
Housing challenges in Saudi Arabia: the shortage of suitable housing units for various socioeconomic segments of Saudi society
Authors: Alqahtany Ali , Bin Mohanna Ameen
Published: August 2019

Purpose

The purpose of this paper is to identify the obstacles to the availability of suitable housing units for various socioeconomic segments of society with an emphasis on single-family homes, which is the most preferred housing type in the Saudi society.

Design/methodology/approach

To achieve the aim of this paper, the Delphi method was used to explore the experts’ opinions on the most important obstacles.

Findings

The findings of the study underline 17 different obstacles affecting the availability of suitable housing units for various segments of the Saudi society. The most critical obstacle is the high cost of land followed by the low income of the families, high cost of construction, high interest rate of mortgages and shortage of suitable residential lands.

Originality/value

The study concludes with a number of proposed recommendations that can contribute to address the current shortage of suitable housing units.
The impact of gender, socioeconomic status and locality on the development of student patterns of alcohol consumption and harm
Authors: Evans Melissa , Lester Leanne , Midford Richard , Cahill Helen Walker , Foxcroft David , Waghorne Robyn , Venning Lynne
Published: August 2019

Purpose

The consequences of problematic alcohol consumption fall heavily on Australian adolescents, with this population at increased risk of death, serious injury and other harm. Research regarding whether gender, socioeconomic status (SES) or locality play a role in young people’s alcohol consumption and related harm is limited in Australia. The purpose of this paper is to determine whether Victorian students’ patterns of alcohol uptake, consumption and related harm differed between gender, SES and locality.

Design/methodology/approach

The study involved secondary analysis of student data from the Drug Education in Victorian Schools harm minimisation drug education programme, undertaken in 21 Victorian government schools over three years The initial cohort of 1,752 students was followed during Years 8, 9 and 10, when their average age would have, respectively, been 13, 14 and 15 years.

Findings

There were no gender differences in drinking uptake, consumption or harm. Students with low SES were more likely to have consumed a full drink of alcohol and also experienced more alcohol-related harm. Students living in a regional/rural area were more likely to have engaged in high alcohol consumption.

Originality/value

The findings of this study highlighted that different student demographics have an impact on patterns of alcohol consumption, vulnerability and harm. Students with low SES, living in a regional/rural area, are more at risk than students with higher SES living in a fringe metro/major regional or metro area. Future school harm minimisation drug education programmes should consider the needs of students with demographics that make them more susceptible to higher consumption and harm.
An epidemic model for correlated information diffusion in crowd intelligence networks
Authors: Li Yuejiang , Zhao H. Vicky , Chen Yan
Published: August 2019

Purpose

With the popularity of the internet and the increasing numbers of netizens, tremendous information flows are generated daily by the intelligently interconnected individuals. The diffusion processes of different information are not independent, and they interact with and influence each other. Modeling and analyzing the interaction between correlated information play an important role in the understanding of the characteristics of information dissemination and better control of the information flows. This paper aims to model the correlated information diffusion process over the crowd intelligence networks.

Design/methodology/approach

This study extends the classic epidemic susceptible–infectious–recovered (SIR) model and proposes the SIR mixture model to describe the diffusion process of two correlated pieces of information. The whole crowd is divided into different groups with respect to their forwarding state of the correlated information, and the transition rate between different groups shows the property of each piece of information and the influences between them.

Findings

The stable state of the SIR mixture model is analyzed through the linearization of the model, and the stable condition can be obtained. Real data are used to validate the SIR mixture model, and the detailed diffusion process of correlated information can be inferred by the analysis of the parameters learned through fitting the real data into the SIR mixture model.

Originality/value

The proposed SIR mixture model can be used to model the diffusion of correlated information and analyze the propagation process.
Integrated palliative care definition and constitutive elements: scoping review
Authors: Mondejar-Pont Meritxell , Ramon-Aribau Anna , Gómez-Batiste Xavier
Published: August 2019

Purpose

The purpose of this paper is to propose a unified definition of integrated palliative care (IPC), and to identify the elements that facilitate or hinder implementation of an integrated palliative care system (IPCS).

Design/methodology/approach

A scoping review of the conceptualization and essential elements of IPC was undertaken, based on a search of the PubMed, Scopus and ISI Web of Science databases. The search identified 79 unduplicated articles; 43 articles were selected for content analysis.

Findings

IPC is coordinated and collaborative across different health organizations, levels of care and types of providers. Eight key elements facilitate implementation of an IPCS: coordination, early patient identification, patient-centered services, care continuity, provider education and training, a standard implementation model and screening tool, shared information technology system, and supportive policies and funding. These elements were plotted as a “Circle of Integrated Palliative Care System Elements.”

Practical implications

This paper offers researchers an inclusive definition of IPC and describes the essential elements of its successful implementation.

Originality/value

This study provides evidence from researchers on five continents, offering insights from multiple countries and cultures on the topic of IPC. The findings of this thematic analysis could assist international researchers aiming to develop a standard evaluative model or assess the level of integration in a health care system’s delivery of palliative care.
Health service literacy: complementary actor roles for transformative value co-creation
Authors: Davey Janet , Grönroos Christian
Published: August 2019

Purpose

Although health-care features prominently in transformative service research, there is little to guide service providers on how to improve well-being and social change transformations. This paper aims to explore actor-level interactions in transformative services, proposing that actors’ complementary health service literacy roles are fundamental to resource integration and joint value creation.

Design/methodology/approach

In-depth interviews with 46 primary health-care patients and 11 health-care service providers (HSPs) were conducted focusing on their subjective experiences of health literacy. An iterative hermeneutic approach was used to analyse the textual data linking it with existing theory.

Findings

Data analysis identified patients’ and HSPs’ health service literacy roles and corresponding role readiness dimensions. Four propositions are developed describing how these roles influence resource integration processes. Complementary service literacy roles enhance resource integration with outcomes of respect, trust, empowerment and loyalty. Competing service literacy roles lead to outcomes of discredit, frustration, resistance and exit through unsuccessful resource integration.

Originality/value

Health service literacy roles – linked to actor agency, institutional norms and service processes – provide a nuanced approach to understanding the tensions between patient empowerment trends and service professionals’ desire for recognition of their expertise over patient care. Specifically, the authors extend Frow et al.’s (2016) list of co-creation practices with practices that complement actors’ service literacy and role readiness. Based on a service perspective, the authors encourage transformative service researchers, service professionals and health service system designers, to recognize complementary health service literacy roles as an opportunity to support patients’ resources and facilitate value co-creation.
Government intervention policies in competition of financial chains: a game theory approach
Authors: Reza-Gharehbagh Raziyeh , Hafezalkotob Ashkan , Makui Ahmad , Sayadi Mohammad Kazem
Published: August 2019

Purpose

This study aims to analyze the competition of two financial chains (FCs) when the government intervenes in the financial market to prohibit the excessively high-interest rate by minimizing the arbitrages caused by speculative transactions. Each FC comprises an investor and one intermediary, attempts to finance the capital-constrained firms in financing needs.

Design/methodology/approach

Using a Stackelberg game theoretic framework and formulating two- and three-level optimization problems for six possible scenarios, the authors establish an integrative framework to evaluate the scenarios through the lens of the two main decision-making structures of the FCs (i.e. centralized and decentralized) and three policies of the government (i.e. speculation minimizing, revenue gaining and utility maximizing).

Findings

Solving the problem results in optimal values for tariffs, which guarantee a stable competitive market. Consequently, policymaking by the government influences the decision variables, which is shown in a numerical study. The authors find that the government can orchestrate the FCs in the competitive market by imposing tariffs and prohibiting high-interest rates via regulating the speculation impacts, which guarantees a stable market and facilitates the financing of capital-constrained firms.

Research limitations/implications

This paper aids the financial markets and governments to control the interest rate by minimizing the speculation level.

Originality/value

This paper investigates the impact of government intervention policies – as a leading player – on the competition of FCs – as followers – in providing financial services and making profits. The government imposes tariffs on the interest rate to stabilize the market by limiting speculative transactions. The paper presents the mathematical models of the optimization problems through the game-theoretic framework and comparison of the scenarios through a numerical experiment.
The relationship between debt and a firm’s performance: the impact of institutional factors
Authors: Forte Rosa , Tavares José Miguel
Published: August 2019

Purpose

The purpose of this paper is to contribute to the existing literature on the relationship between debt and firms’ performance, by focusing on the influence of the institutional framework on this relationship and on the role of macroeconomic variables in explaining performance.

Design/methodology/approach

The present work is based on a large sample of 48,840 manufacturing firms from nine European countries covering the 2008–2013 period and uses a fixed effects model.

Findings

Results show that the impact of debt on a firm’s performance depends on the measure of debt (short-term debt positively affects a firm’s performance, whereas long-term debt presents a negative relationship) and that the institutional framework is indeed affecting the relationship between debt and a firm’s performance: the positive effect of debt on a firm’s performance tends to be higher the greater the “efficiency of the legal system” and the greater the “credit market regulation.” Macroeconomic variables also play a key role in explaining performance.

Originality/value

Unlike most of the existing studies, which focus only on the relationship between debt and firms’ performance in a single country, the present work uses a sample of firms from nine countries with the purpose of filling a research gap and bringing new empirical evidence to this research area.
Security tokens: architecture, smart contract applications and illustrations using SAFE
Authors: Subramanian Hemang
Published: August 2019

Purpose

Blockchain technologies have pervaded modern crowdfunding and capital sourcing through a variety of financial instruments implemented as smart contracts. Smart contracts provide a unique mechanism not only to create a unique one-of-a-type financial instrument, but also to enable unique innovations atop existing financial instruments due to underlying efficiencies. The smartness comes from the flexibility that programs provide which can create extremely unique financial instruments that are often complex to implement, yet easy to create, maintain through versioning, trade and destroy. The purpose of this paper is to describe the security token architecture as an application of smart contracts. Further, the author illustrates the implementation and design of a commonly used financial instrument known as Simple Agreement for Future Equity (SAFE) using the security token architecture proposed and smart contract functionality. The author then models the transaction using relational algebra, and, models the utility maximization. The author shows how on account of reduced information asymmetry between the investors and SAFE users (i.e. startups) utility is positive when smart contract-based security tokens are deployed for each state in the SAFE contract.

Design/methodology/approach

Using an existing well-adopted instrument called a SAFE contract, the author illustrates the architecture of a smart contract-based security token system. The author illustrates how different components of a SAFE contract can be implemented as a smart contract and discusses the advantages and disadvantages of applying blockchain-based smart contracts to design SAFE instruments. The author deploys two methods: a state space diagram to explain state transitions and a utility model to explain the utilities.

Findings

The key findings of this research study are the design of a security token architecture, which can be used to convert any the physical or contract-based financial instrument to a smart contract that runs on the blockchain. However, there are limitations to the implementation of the same which can be overcome. The model illustrates the positive utilities derived for all economic actors, i.e. the contractors, the utility providers, etc., in the market.

Originality/value

This paper is an original paper. For the very first time, the author explored the architecture of a security token system. Using a well-known financial instrument, namely the SAFE, the author describes various components, e.g. the four contracts that form SAFE and then model the utilities for the system.
Mentoring for employability: a state-level impact study
Authors: Jackson Claire , Milos Dani , Kerr Monica
Published: August 2019

Purpose

Industry mentoring has been repeatedly called out in sector reports on research training in Australian Universities as an effective way to develop PhD capacity and capabilities during research degrees (ACOLA, 2016; NOUS, 2017). Despite the understood importance of this type of experiential development, there is little published evidence on how effective mentoring is to develop the capabilities linked to improved employability. The University of South Australia developed the industry mentoring network in STEM (IMNIS) Impact Evaluation Instrument (IIEI) to capture advanced self-assessed data from mentees and demonstrate what impact the IMNIS program has on developing industry-relevant knowledge and skills in PhD participants. In 2017, the three universities in South Australia implemented a state-wide study using the IIEI to understand the impact of the national IMNIS scheme on the South Australian cohort.

Design/methodology/approach

This paper presents a case study on the impact of mentoring on PhD students during the IMNIS program. A self-assessed, competency-based study design has been used to collect pre, mid and post experience data, which measures the extent to which objectives of the IMNIS program are met. The evaluation of the results, using the Vitae Impact Framework (Vitae, 2012), seeks to understand the development of mentees’ skills and knowledge as a result of their mentoring experience to support program development and build an evidence base of impact.

Findings

This paper presents the 2017/2018 results from the South Australian IMNIS impact evaluation. Through analysis of the three data sets, findings show that skills and knowledge have been developed in mentees as a result of the program.

Originality/value

This study provides an extended approach to the existing evaluation undertaken in the national IMNIS program. The IIEI is now available for other universities to use as a method for extended evaluation of their IMNIS program or potentially other WIL opportunities, providing an opportunity for institutional and national benchmarking.
Machine learning framework for predicting reliability of solder joints
Authors: Yi Sung , Jones Robert
Published: August 2019

Purpose

This paper aims to present a machine learning framework for using big data analytics to predict the reliability of solder joints. The purpose of this study is to accurately predict the reliability of solder joints by using big data analytics.

Design/methodology/approach

A machine learning framework for using big data analytics is proposed to predict the reliability of solder joints accurately.

Findings

A machine learning framework for predicting the life of solder joints accurately has been developed in this study. To validate its accuracy and efficiency, it is applied to predict the long-term reliability of lead-free Sn96.5Ag3.0Cu0.5 (SAC305) for three commonly used surface finishes such OSP, ENIG and IAg. The obtained results show that the predicted failure based on the machine learning method is much more accurate than the Weibull method. In addition, solder ball/bump joint failure modes are identified based on various solder joint failures reported in the literature.

Originality/value

The ability to predict thermal fatigue life accurately is extremely valuable to the industry because it saves time and cost for product development and optimization.
Beyond hijabs and Ramadan
Authors: Torres Heidi J.
Published: August 2019

Purpose

The purpose of this paper is to describe an integrated social studies and literacy unit designed to teach about Islam in elementary classrooms. Concerns regarding teaching about religion in public schools are addressed, and a rationale is provided for specifically teaching about Islam.

Design/methodology/approach

The unit is described in detail, outlining key ideas and purposes for the unit’s scope, sequence and activities. Several extensions to the unit are included, as well as suggestions on how to address difficult topics that might arise.

Findings

Students participating in this unit exhibited interest and curiosity about Islam and Muslims, indicated by their desire to ask questions, discuss issues and engage in the activities. Reflections at the end of the unit indicate that students learned new information and ideas about Islam and Muslims.

Practical implications

The unit described in this paper as well as the resources and suggestions provide a framework for teachers who want to teach about Islam to elementary-aged children.

Originality/value

Although there are a number of articles in the literature that address ideas on teaching about Islam or other religions in the classroom, there are few that provide practical, specific, pedagogical information for doing so, particularly at the elementary level. This paper strives to contribute toward that aim.
Entrepreneurial learning in venture acceleration programs
Authors: Politis Diamanto , Gabrielsson Jonas , Galan Nataliya , Abebe Solomon Akele
Published: August 2019

Purpose

This study aims to better understand entrepreneurial learning in the context of venture acceleration programs.

Design/methodology/approach

A qualitative research strategy was used based on multiple in-depth interviews with 21 lead entrepreneurs complemented with participatory observations and secondary sources. The data were inductively analysed following the Gioia methodology (Gioia et al., 2012).

Findings

The authors build on experiential learning theory to generate a process-focussed model exploring the learning dynamics that venture acceleration programs can facilitate. In this model, the authors identify three catalysts that trigger processes of experiential learning and two contingencies that alleviate the effects of the catalysts on learning outcomes. The findings suggest that the potential of venture acceleration programs to be effective learning environments pends on the presence and quality of these catalysts and contingencies.

Originality/value

The findings provide novel insights on how venture acceleration programs trigger entrepreneurial learning, thereby offering a deeper understanding of the learning dynamics in this setting.