bluuebunny/crossref_metadata_2025 huggingface dataset:
MetaPrism: A Toolkit for Joint Taxa/Gene Analysis of Metagenomic Sequencing Data
Authors: Kim Jiwoong , Jiang Shuang , Xiao Guanghua , Xie Yang , Liu Dajiang J. , Li Qiwei , Koh Andrew , Zhan Xiaowei
Published: June 2019

Background

In microbiome research, metagenomic sequencing generates enormous amounts of data. These data are typically classified into taxa for taxonomy analysis, or into genes for functional analysis. However, a joint analysis where the reads are classified into taxa-specific genes is often overlooked.

Result

To enable the analysis of this biologically meaningful feature, we developed a novel bioinformatic toolkit, MetaPrism, which can analyze sequence reads for a set of joint taxa/gene analyses: 1) classify sequence reads and estimate the abundances for taxa-specific genes; 2) tabularize and visualize taxa-specific gene abundances; 3) compare the abundances between groups, and 4) build prediction models for clinical outcome. We illustrated these functions using a published microbiome metagenomics dataset from patients treated with immune checkpoint inhibitor therapy and showed the joint features can serve as potential biomarkers to predict therapeutic responses.

Conclusions

MetaPrism is a toolkit for joint taxa and gene analysis. It offers biological insights on the taxa-specific genes on top of the taxa-alone or gene-alone analysis.

MetaPrism is open source software and freely available at https://github.com/jiwoongbio/MetaPrism. The example script to reproduce the manuscript is also provided in the above code repository.
Network synchronization and synchrony propagation: emergent elements of inspiration
Authors: Ashhad Sufyan , Feldman Jack L
Published: June 2019

The preBötzinger Complex (preBötC) – the kernel of breathing rhythmogenesis in mammals – is a non-canonical central pattern generator with undetermined mechanisms. We assessed preBötC network dynamics under respiratory rhythmic and nonrhythmic conditions in vitro. In each cycle under rhythmic conditions, an inspiratory burst emerges as (presumptive) preBötC rhythmogenic neurons transition from aperiodic uncorrelated population spike activity to become increasingly synchronized during preinspiration, triggering bursts; burst activity subsides and the cycle repeats. In a brainstem slice in nonrhythmic conditions, antagonizing GABAA receptors can initiate this periodic synchronization and consequent rhythm coincident with inducing a higher conductance state in nonrhythmogenic preBötC output neurons. Furthermore, when input synchrony onto these neurons was weak, preBötC activity failed to propagate to motor nerves. Our analyses uncover a dynamic reorganization of preBötC network activity – underpinning intricate cyclic neuronal interactions leading to network synchronization and its efficient propagation – correlated with and, we postulate, essential to, rhythmicity.
Endothelial CXCL5 negatively regulates myelination and repair after white matter stroke
Authors: Xiao Guanxi , Kumar Rosie , Komuro Yutaro , Burguet Jasmine , Kakarla Visesha , Azizkhanian Ida , Sheth Sunil A. , Williams Christopher K. , Zhang Xinhai R. , Macknicki Michal , Brumm Andrew , Kawaguchi Riki , Mai Phu , Kaneko Naoki , Vinters Harry V. , Carmichael S. Thomas , Havton Leif A. , DeCarli Charles , Hinman Jason D.
Published: June 2019

Cerebral small vessel disease and resulting white matter pathologies are worsened by cardiovascular risk factors including obesity. The molecular changes in cerebral endothelial cells caused by chronic cerebrovascular risk factors remain unknown. We developed a novel approach for molecular profiling of chronically injured cerebral endothelial cells using cell-specific translating ribosome affinity purification (RiboTag) with RNA-seq in Tie2-Cre:RiboTag mice. We used this approach to identify the transcriptome of white matter endothelial cells after the onset of diet-induced obesity (DIO). DIO induces an IL-17B signaling pathway that acts on the cerebral endothelia through IL-17Rb to increase levels of both circulating CXCL5 and local endothelial expression of CXCL5 in both the DIO mouse model and in humans with imaging or pathologic evidence of cerebral small vessel disease. In the white matter, endothelial CXCL5 acts as a chemoattractant and promotes the association of oligodendrocyte progenitor cells (OPCs) with cerebral endothelia increasing vessel-associated OPC cell number and triggers OPC gene expression programs regulating migration and chemokine receptor activation. Targeted blockade of IL-17B with peripheral antibody administration reduced the population of vessel-associated OPCs by reducing endothelial CXCL5 expression. CXCL5-mediated sequestration of OPCs to white matter vasculature impairs OPC differentiation after a focal white matter ischemic lesion. DIO promotes a unique white matter endothelial-to-oligodendrocyte progenitor cell signaling pathway that compromises brain repair after stroke.
Uncertainty quantification of parenchymal tracer distribution using random diffusion and convective velocity fields
Authors: Croci Matteo , Vinje Vegard , Rognes Marie E.
Published: June 2019

Background

Influx and clearance of substances in the brain parenchyma occur by a combination of diffusion and convection, but the relative importance of thiese mechanisms is unclear. Accurate modeling of tracer distributions in the brain relies on parameters that are partially unknown and with literature values varying up to 7 orders of magnitude. In this work, we rigorously quantified the variability of tracer enhancement in the brain resulting from uncertainty in diffusion and convection model parameters.

Methods

In a mesh of a human brain, using the convection-diffusion-reaction equation, we simulated tracer enhancement in the brain parenchyma after intrathecal injection. Several models were tested to assess the uncertainty both in type of diffusion and velocity fields and also the importance of their magnitude. Our results were compared with experimental MRI results of tracer enhancement.

Results

In models of pure diffusion, the expected amount of tracer in the gray matter reached peak value after 15 hours, while the white matter does not reach peak within 24 hours with high likelihood. Models of the glymphatic system behave qualitatively similar as the models of pure diffusion with respect to expected time to peak but display less variability. However, the expected time to peak was reduced to 11 hours when an additional directionality was prescribed for the glymphatic circulation. In a model including drainage directly from the brain parenchyma, time to peak occured after 6-8 hours for the gray matter.

Conclusion

Even when uncertainties are taken into account, we find that diffusion alone is not sufficient to explain transport of tracer deep into the white matter as seen in experimental data. A glymphatic velocity field may increase transport if a directional structure is included in the glymphatic circulation.
Somatic drift and rapid loss of heterozygosity suggest small effective population size of stem cells and high somatic mutation rate in asexual planaria
Authors: Asgharian Hosseinali , Dunham Joseph , Marjoram Paul , Nuzhdin Sergey V.
Published: June 2019

Planarian flatworms have emerged as highly promising models of body regeneration due to the many stem cells scattered through their bodies. Currently, there is no consensus as to the number of stem cells active in each cycle of regeneration or the equality of their relative contributions. We approached this problem with a population genetic model of somatic genetic drift. We modeled the fissiparous life cycle of asexual planarians as an asexual population of cells that goes through repeated events of splitting into two subpopulations followed by population growth to restore the original size. We sampled a pedigree of obligate asexual clones ofGirardia cf. tigrinaat multiple time points encompassing 14 generations. Effective population size of stem cells was inferred from the magnitude of temporal fluctuations in the frequency of somatic variants and under most of the examined scenarios was estimated to be in the range of a few hundreds. Average genomic nucleotide diversity was 0.00398. Assuming neutral evolution and mutation-drift equilibrium, the somatic mutation rate was estimated in the 10−5− 10−7range. Alternatively, we estimatedNeand somaticμfrom temporal changes in nucleotide diversityπwithout the assumption of equilibrium. This second method suggested even smallerNeand largerμ. A key unknown parameter in our model on which estimates ofNeandμdepend isg, the ratio of cellular to organismal generations determined by tissue turnover rate. Small effective number of propagating stem cells might contribute to reducing reproductive conflicts in clonal organisms.
Heading choices of flyingDrosophilaunder changing angles of polarized light
Authors: Mathejczyk Thomas F. , Wernet Mathias F.
Published: June 2019

Many navigating insects include the celestial polarization pattern as an additional visual cue to orient their travels. Spontaneous orientation responses of both walking and flying fruit flies (Drosophila melanogaster) to linearly polarized light have previously been demonstrated. Using newly designed modular flight arenas consisting entirely of off-the-shelf parts and 3D-printed components we present individual flying flies with a slow and continuous rotational change in the incident angle of linear polarization. Under such open-loop conditions, single flies choose arbitrary headings with respect to the angle of polarized light and show a clear tendency to maintain those chosen headings for several minutes, thereby adjusting their course to the slow rotation of the incident stimulus. Importantly, flies show the tendency to maintain a chosen heading even when two individual test periods under a linearly polarized stimulus are interrupted by an epoch of unpolarized light lasting several minutes. Finally, we show that these behavioral responses are wavelength-specific, existing under polarized UV stimulus while being absent under polarized green light. Taken together, these findings provide further evidence supporting Drosophila’s abilities to use celestial cues for visually guided navigation and course correction.
Left prefrontal impact links subthalamic stimulation with depressive symptoms
Authors: Irmen Friederike , Horn Andreas , Mosley Philip , Perry Alistair , Petry-Schmelzer Jan Niklas , Dafsari Haidar S. , Barbe Michael , Visser-Vandewalle Veerle , Schneider Gerd-Helge , Li Ningfei , Kübler Dorothee , Wenzel Gregor , Kühn Andrea
Published: June 2019

Objective

Subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson’s Disease (PD) not only stimulates focal target structures but also affects distributed brain networks. The impact this network modulation has on non-motor DBS effects is not well characterized. By focusing on the affective domain, we systematically investigate the impact of electrode placement and associated structural connectivity on changes in depressive symptoms following STN-DBS which have been reported to improve, worsen or remain unchanged.

Methods

Depressive symptoms before and after STN-DBS surgery were documented in 116 PD patients from three DBS centers (Berlin, Queensland, Cologne). Based on individual electrode reconstructions, the volumes of tissue activated (VTA) were estimated and combined with normative connectome data to identify structural connections passing through VTAs. Berlin and Queensland cohorts formed a training and cross-validation dataset used to identify structural connectivity explaining change in depressive symptoms. The Cologne data served as test-set for which depressive symptom change was predicted.

Results

Structural connectivity was linked to depressive symptom change under STN-DBS. An optimal connectivity map trained on the Berlin cohort could predict changes in depressive symptoms in Queensland patients and vice versa. Furthermore, the joint training-set map predicted changes in depressive symptoms in the independent test-set. Worsening of depressive symptoms was associated with left prefrontal connectivity.

Interpretation

Fibers linking the STN electrode with left prefrontal areas predicted worsening of depressive symptoms. Our results suggest that for the left STN-DBS lead, placement impacting fibers to left prefrontal areas should be avoided to maximize improvement of depressive symptoms.
Quickly fading afterimages: hierarchical adaptations in human perception
Authors: Klinger Madeline E. , Kell Christian A. , Nikolić Danko
Published: June 2019

Afterimages result from a prolonged exposure to still visual stimuli. They are best detectable when viewed against uniform backgrounds and can persist for multiple seconds. Consequently, the dynamics of afterimages appears to be slow by their very nature. To the contrary, we report here that about 50% of an afterimage intensity can be erased rapidly—within less than a second. The prerequisite is that subjects view a rich visual content to erase the afterimage; fast erasure of afterimages does not occur if subjects view a blank screen. Moreover, we find evidence that fast removal of afterimages is a skill learned with practice as our subjects were always more effective in cleaning up afterimages in later parts of the experiment. These results can be explained by a tri-level hierarchy of adaptive mechanisms, as has been proposed by the theory of practopoiesis.
Is it Time to Switch Your T1W Sequence? Assessing the Impact of Prospective Motion Correction on the Reliability and Quality of Structural Imaging
Authors: Ai Lei , Craddock R. Cameron , Tottenham Nim , Dyke Jonathan P , Lim Ryan , Colcombe Stanley , Milham Michael , Franco Alexandre R.
Published: June 2019

New large neuroimaging studies, such as the Adolescent Brain Cognitive Development study (ABCD) and Human Connectome Project (HCP) Development studies are adopting a new T1-weighted imaging sequence with prospective motion correction (PMC) in favor of the more traditional 3-Dimensional Magnetization-Prepared Rapid Gradient-Echo Imaging (MPRAGE) sequence. Here, we used a developmental dataset (ages 5-21, N=348) from the Healthy Brain Network (HBN) Initiative to directly compare two widely used MRI structural sequences: one based on the Human Connectome Project (MPRAGE) and another based on the ABCD study (MPRAGE+PMC). We aimed to determine if the morphometric measurements obtained from both protocols are equivalent or if one sequence has a clear advantage over the other. The sequences were also compared through quality control measurements. Inter- and intra-sequence reliability were assessed with another set of participants (N=71) from HBN that performed two MPRAGE and two MPRAGE+PMC sequences within the same imaging session, with one MPRAGE (MPRAGE1) and MPRAGE+PMC (MPRAGE+PMC1) pair at the beginning of the session and another pair (MPRAGE2 and MPRAGE+PMC2) at the end of the session. Intraclass correlation coefficients (ICC) scores for morphometric measurements such as volume and cortical thickness showed that intra-sequence reliability is the highest with the two MPRAGE+PMC sequences and lowest with the two MPRAGE sequences. Regarding inter-sequence reliability, ICC scores were higher for the MPRAGE1 - MPRAGE+PMC1 pair at the beginning of the session than the MPRAGE1 - MPRAGE2 pair, possibly due to the higher motion artifacts in the MPRAGE2 run. Results also indicated that the MPRAGE+PMC sequence is robust, but not impervious, to high head motion. For quality control metrics, the traditional MPRAGE yielded better results than MPRAGE+PMC in 5 of the 8 measurements. In conclusion, morphometric measurements evaluated here showed high inter-sequence reliability between the MPRAGE and MPRAGE+PMC sequences, especially in images with low head motion. We suggest that studies targeting hyperkinetic populations use the MPRAGE+PMC sequence, given its robustness to head motion and higher reliability scores. However, neuroimaging researchers studying non-hyperkinetic participants can choose either MPRAGE or MPRAGE+PMC sequences, but should carefully consider the apparent tradeoff between relatively increased reliability, but reduced quality control metrics when using the MPRAGE+PMC sequence.
Regioselective synthesis and characterization of monovanadium-substituted β-octamolybdate [VMo7O26]5−
Authors: Krivosudský Lukáš , Roller Alexander , Rompel Annette
Published: June 2019

The monovanadium-substituted polyoxometalate anion [VMo7O26]5−, exhibiting a β-octamolybdate archetype structure, was selectively prepared as pentapotassium [hexaikosaoxido(heptamolybdenumvanadium)]ate hexahydrate, K5[VMo7O26]·6H2O (VMo7
), by oxidation of a reduced vanadomolybdate solution with hydrogen peroxide in a fast one-pot approach. X-ray structure analysis revealed that the V atom occupies a single position in the cluster that differs from the other positions by the presence of one doubly-bonded O atom instead of two terminal oxide ligands in all other positions. The composition and structure of VMo7
was also confirmed by elemental analyses and IR spectroscopy. The selectivity of the synthesis was inspected by a 51V NMR investigation which showed that this species bound about 95% of VV in the crystallization solution. Upon dissolution of VMo7
in aqueous solution, the [VMo7O26]5− anion is substantially decomposed, mostly into [VMo5O19]3−, α-[VMo7O26]4− and [V2Mo4O19]4−, depending on the pH.
Edifying role of corporate reputation in new issue market: Indian evidence
Authors: Kaur Amanpreet , Singh Balwinder
Published: June 2019

Purpose

The purpose of this paper is to examine the relationship between corporate reputation and initial public offering (IPO) underpricing for a sample of 269 IPOs hitting the Indian capital market for the first time during the period ranging from April 1, 2007 to November 8, 2016.

Design/methodology/approach

The study is based on secondary data (of 269 Indian companies going public) obtained from websites of capital market, Chittorgarh and Securities and Exchange Board of India (from where prospectus of each company was downloaded individually to extract data on financial variables). The study devises the technique of multivariate regression analysis to arrive at the results.

Findings

The results of the study reveal that corporate reputation serves as a signal to naive investors that assures them of issuer company’s credibility, resulting in lower underpricing. In addition to it, the study also observes the level of gender diversity on Indian boards. It is disappointing to notice low level of female representation on Indian boards and the improvement if any made in the number of female directors on Indian boards is due to provisions of new companies’ act, 2013 that mandates at least one women director on the board of every listed company. Thus, females do not constitute a critical mass on Indian boards.

Research limitations/implications

The current study scrutinizes the impact of corporate reputation on IPO underpricing only. Furthermore, the study analyzes the underpricing of only book built IPOs. Incorporating both book built and fixed price IPOs could have provided better insights into the issue.

Practical implications

The study outlines significant implications for managers of issuer company to portray company’s own reputation as a signal instead of showcasing borrowed reputation of external agents at the crucial juncture of going public.

Originality/value

Many signals portraying quality of the offering are sent by issuer company in public arena to make IPO launch a successful event. Among many such signals like underwriting reputation, auditor reputation, director’s and CEO’s reputation, the corporate audience has started giving more impetus to issuer company’s own reputation. Thus, financial academia witnessed a paradigm shift from external agents reputation to internal agent’s reputation and now the loci of interest has shifted to company’s own reputation. Giving emphasis to corporate reputation seems more relevant in emerging economies like India where naive investors rely on their own judgments while making investment decision who take clue from various signals to infer quality of the offer. It is momentous to observe whether reputation of the company acts as a conspicuous signal to decipher IPO quality. Furthermore, there hardly exists any empirical research directly examining the impact of corporate reputation on IPO underpricing in the Indian context. Hence, the present study is a modest attempt to fill this gap in literature.
Diversification-based learning simulated annealing algorithm for hub location problems
Authors: Rathore Himanshu , Nandi Shirsendu , Pandey Peeyush , Singh Surya Prakash
Published: June 2019

Purpose

The purpose of this paper is to examine the efficacy of diversification-based learning (DBL) in expediting the performance of simulated annealing (SA) in hub location problems.

Design/methodology/approach

This study proposes a novel diversification-based learning simulated annealing (DBLSA) algorithm for solving p-hub median problems. It is executed on MATLAB 11.0. Experiments are conducted on CAB and AP data sets.

Findings

This study finds that in hub location models, DBLSA algorithm equipped with social learning operator outperforms the vanilla version of SA algorithm in terms of accuracy and convergence rates.

Practical implications

Hub location problems are relevant in aviation and telecommunication industry. This study proposes a novel application of a DBLSA algorithm to solve larger instances of hub location problems effectively in reasonable computational time.

Originality/value

To the best of the author’s knowledge, this is the first application of DBL in optimisation. By demonstrating its efficacy, this study steers research in the direction of learning mechanisms-based metaheuristic applications.
A rapid stress calculation method for short flexspline harmonic drive
Authors: Wang Shuang , Jiang Gedong , Mei Xuesong , Zou Chuang , Zhang Xian , Zhang Hao
Published: June 2019

Purpose

Because of the compact structure, short flexspline (FS) harmonic drive (HD) is increasingly used. The stress calculation of FS is very important in design and optimization of HD system. This paper aims to study the stress calculation methods for short FS, based on mechanics analysis and finite element method (FEM).

Design/methodology/approach

A rapid stress calculation method, based on mechanics analysis, is proposed for the short FS of HD. To verify the stress calculation precision of short FS, a complete finite element model of HD is established. The results of stress and deformation of short FS in different lengths are solved by FEM.

Findings

Through the rapid calculation method, the analytical relationship between circumferential stress and length of cylinder was obtained. And the circumferential stress has proportional relation with the reciprocal of squared length. The FEM results verified that the rapid stress calculation method could obtain accurate results.

Research limitations/implications

The rapid mechanics analysis method is practiced to evaluate the strength of FS at the design stage of HD. And the complete model of HD could contribute to improving the accuracy of FEM results.

Originality/value

The rapid calculation method is developed based on mechanics analysis method of cylinder and equivalent additional bending moment model, through which the analytical relationship between circumferential stress and length of cylinder was obtained. The complete three-dimensional finite element model of HD takes the stiffness of bearing into consideration, which can be used in the numerical simulation in the future work to improve the accuracy.
A novel scheme for imposing periodic boundary conditions on RVE in second-order computational homogenization for granular material
Authors: Li Xikui , Zhang Songge , Duan Qinglin
Published: June 2019

Purpose

This paper aims to present a novel scheme for imposing periodic boundary conditions with downscaled macroscopic strain measures of gradient Cosserat continuum on the representative volume element (RVE) of discrete particle assembly in the frame of the second-order computational homogenization methods for granular materials.

Design/methodology/approach

The proposed scheme is based on the generalized Hill’s lemma of gradient Cosserat continuum and the incremental non-linear constitutive relation condensed to the peripheral particles of the RVE of discrete particle assembly. The generalized Hill’s lemma conducts to downscale the macroscopic strain or stress measures and to impose the periodic boundary conditions on the RVE boundary so that the Hill-Mandel energy equivalence condition is ensured. Because of the incremental non-linear constitutive relation condensed to the peripheral particles of the RVE, the periodic boundary displacement and traction constraints together with the downscaled macroscopic strains and strain gradients, micro-rotations and curvatures are imposed in the point-wise sense without the need of introducing the Lagrange multipliers for enforcing the periodic boundary displacement and traction constraints in a weak sense.

Findings

Numerical results demonstrate that the applicability and effectiveness of the proposed scheme in imposing the periodic boundary conditions on the RVE. The results of the RVE subjected to the periodic boundary conditions together with the displacement boundary conditions in the second-order computational homogenization for granular materials provide the desired estimations, which lie between the upper and the lower bounds provided by the displacement and the traction boundary conditions imposed on the RVE respectively.

Research limitations/implications

Each grain in the particulate system under consideration is assumed to be rigid and circular.

Practical implications

The proposed scheme for imposing periodic boundary conditions on the RVE can be adopted solely for estimating the effective mechanical properties of granular materials and/or integrated into the frame of the second-order computational homogenization method with a nested finite element method-discrete element method solution procedure for granular materials. It will tend to provide, at least theoretically, more reasonable results for effective material properties and solutions of a macroscopic boundary value problem simulated by the computational homogenization method.

Originality/value

This paper presents a novel scheme for imposing periodic boundary conditions with downscaled macroscopic strain measures of gradient Cosserat continuum on the RVE of discrete particle assembly for granular materials without need of introducing Lagrange multipliers for enforcing periodic boundary conditions in a weak (integration) sense.
Work-to-family and family-to-work conflicts among employed single parents in Germany
Authors: Reimann Mareike , Marx Charlotte Katharina , Diewald Martin
Published: June 2019

Purpose

The purpose of this paper is to examine whether and how employed single-parents differ from parents in two-parent families in their experience of work-to-family conflict (WFC) and family-to-work conflict (FWC). Looking at job-related as well as family-related demands and resources, this research investigated to what degree these demands and resources contribute to differences in WFC and FWC, how their relevance in predicting conflicts varies between single parents and other parents and the role of compositional differences in work and family demands and resources.

Design/methodology/approach

Cross-sectional linear regression analyses were applied to analyze a random sample of employees in large work organizations in Germany. The sample included 3,581 parents with children up to the age of 25, of whom 346 were single parents.

Findings

The results indicated that single parents face more FWC, but not more WFC, than other parents. For all parents, job demands such as overtime, supervising responsibilities and availability expectations were associated with higher levels of WFC, whereas job resources such as job autonomy, support from supervisors and flexible working hours were associated with lower levels of WFC. In predicting FWC, family demands and resources played only a minor role. However, results provide only scant evidence of differences between single parents and other parents in terms of the effects of job and family demands and resources.

Originality/value

This study offers interesting insights into the diversity of WFC and FWC experiences in Germany. It provides first evidence of the impact of job and family demands and resources on both directions of work–family conflicts among employed single parents as a specific social group.
Using strength-based approaches to fulfil academic potential in degree apprenticeships
Authors: Saville Kelly-Mae , Birdi Gurkiran , Hayes Sarah , Higson Helen , Eperjesi Frank
Published: June 2019

Purpose

The purpose of this paper is to highlight the positive academic and professional outcomes for students who undertake degree apprenticeships which use strength-based approaches in their curriculum and assessment. The design and implementation of programmes of work-based study which focus on an individual’s inherent talents are a new lens for higher education (HE), one that enables institutions to see diverse groups of students fulfil their potential and gain academic qualifications. Strength-based degree apprenticeships offer an effective way to align the needs of industry with the ambitions of individuals who wish to gain university level qualifications whilst in the workplace.

Design/methodology/approach

The research adopted a mixed-methods approach. Semi-structured interviews with stakeholders in industry and HE were undertaken and thematically analysed. Student data were analysed quantitatively for students in the degree apprenticeship programmes which incorporate a strength-based approach to learning and assessment.

Findings

The findings from this study highlight that the degree apprenticeships’ strength-based curriculum and assessment have spearheaded its success. On average, degree apprentices attain 10 per cent higher grades than students undertaking the same programme through the traditional degree route. Moreover, the module design and tailored support has contributed to over 91 per cent of apprentices graduating with a 2:1 or above.

Research limitations/implications

This research is exploratory in nature, focusing on one university’s experiences and outcomes regarding a strength-based approach curriculum and assessment on degree apprenticeships.

Originality/value

The findings describe how the knowledge exchange and culture of the HE sector has shifted, and the university’s efforts to make progressive relationships with employers. Moreover, this paper describes the challenges in designing curricula and assessing students based on the strengths and skills required for their employment, rather than university mandated learning outcomes. The findings of this paper could influence a strength-based framework for the development of degree apprenticeships in the UK.
Computer simulation of weld toe stress concentration factor sequence for fatigue analysis
Authors: Hou Chien-Yuan
Published: June 2019

Purpose

The purpose of this paper is to complete fatigue analysis of welded joints considering both the crack initiation sites and crack coalescence, and to generate virtual welded specimens for computer simulation of fatigue life on a specimen-by-specimen basis; knowledge regarding the weld toe stress concentration factor (SCF) sequence is essential. In this study, attempts were made to analyze the sequence and to find a simple method to generate the sequence using computers.

Design/methodology/approach

Laser scanning technique was used to acquire the real three-dimensional weld toe geometry of welded specimens. The scanned geometry was digitally sectioned, and three-dimensional finite element (FE) models of the scanned specimens were constructed and the weld toe SCF sequence was calculated. The numbers in the sequence were analyzed using a simple autoregression model and the statistical properties of the sequence were acquired.

Findings

The autoregression analysis showed the value of a weld toe SCF is linearly related to its neighboring factor with a high correlation. When a factor value at a toe location is known, the neighboring factor can be simulated by a simple linear equation with a random residual. The weld toe factor sequence can thus be formed by repeatedly using the linear equation with a residual. The generated sequence exhibits close statistical properties to those of the real sequence obtained from FE results.

Practical implications

When the weld toe SCF sequence is known, it is possible to foresee potential crack locations and the subsequent crack coalescence. The results of the current study will be the foundation for the future work on fatigue analysis of welded joints considering the effects of crack initiation site and crack coalescence.

Originality/value

The weld toe SCF sequence was rarely discussed previously because of a lack of the available data. The current study is the first work to investigate the statistical properties of the sequence and found that a simple autoregression equation can be used to perform the analysis. This study is also the first work that successfully generates a weld toe SCF sequence, which can be used to simulate virtual welded specimens.
Understanding circular economy awareness and practices in manufacturing firms
Authors: Liakos Nikolaos , Kumar Vikas , Pongsakornrungsilp Siwarit , Garza-Reyes Jose Arturo , Gupta Bhumika , Pongsakornrungsilp Pimlapas
Published: June 2019

Purpose

Circular economy (CE) has evolved as a result of the growing environmental awareness, environmental legislation and the need for social responsibility. However, awareness levels of CE are not as high as expected and practices are further behind than they should be, with a significant lack of research around the subject in the literature. Therefore, the purpose of this paper is to examine the current state of awareness levels and the practices around CE in manufacturing firms. Moreover, the study aims to empirically validate one of the earlier proposed CE models.

Design/methodology/approach

The study adopts a quantitative survey questionnaire based approach. More than 500 people from various manufacturing organisations were contacted directly over a 40-day long sampling process through the FAME database, personal contacts and LinkedIn. The survey resulted in 103 completed responses. Given the exploratory nature of the study, the data were mainly analysed using descriptive statistics. To validate the CE model, a correlation analysis was also conducted.

Findings

The research findings show that with the growing emphasis on CE across the globe by governing bodies, firms are becoming more aware of CE practices. The analysis also shows some useful insights on the state of each of the pillars (economic benefits, environmental impact and resource scarcity) of CE. The findings also indicate that the environmental impact pillar of CE is at a more developed state than the other two pillars which are, mostly, in a research state.

Research limitations/implications

The study provides manufacturing firms with a thorough understanding of the state of CE practices and importance of its successful implementation. The findings of the study advocates consideration of all three pillars of CE by managers as a guide to plan for an efficient strategy around CE implementation. Moreover, our study adds to existing efforts by the academic community to raise the awareness towards CE practice among all relevant stakeholders. The findings of this study are based on the responses from a limited 103 survey responses from manufacturing firms.

Originality/value

This study adds to the very limited empirical literature on CE awareness and practices in manufacturing firms. This is also one of the first studies attempting to empirically validate an existing CE model.
Virtual currency in sanctioned jurisdictions: stepping outside of SWIFT
Authors: Kirkpatrick Katherine , Savage Christine , Johnston Russell , Hanson Matthew
Published: June 2019

Purpose

To understand and analyze sanctions evasion and enforcement via virtual currencies.

Design/methodology/approach

Discusses various jurisdictions’ attempts to further the use of virtual currency to facilitate and maximize access to international funds; analyzes the aspects that make virtual currency uniquely suited to evade sanctions; suggests best practices for industry participants to be sure to account for the differences in crypto asset structure and related risks.

Findings

The US Treasury Department’s Office of Foreign Assets Control (OFAC) has explicitly stated that despite virtual currency’s anonymity, industry participants are still responsible for policing and enforcing client compliance. Although sanctioned jurisdictions are thinking creatively about ways around SWIFT, the use of virtual currency to skirt sanctions presents certain challenges.

Practical implications

Virtual currency industry participants should understand OFAC’s specific guidance regarding compliance obligations in the cryptocurrency space, and should implement best practices and conservative measures to avoid unknowingly running afoul of sanctions laws.

Originality/value

Expert analysis and guidance from experienced investigations and sanctions lawyers.
Buffering the service failure-induced effect of anger on revenge
Authors: Walsh Gianfranco , Deseniss Alexander , Ivens Stefan , Schaarschmidt Mario
Published: June 2019

Purpose

This paper aims to increase understanding of how the strength of the relationship between service failure-induced customer anger and revenge intentions might be influenced by attitudinal moderators that are both within and outside the realm of the service firm’s control. Drawing on past research, the authors hypothesize that customers’ perceptions of the corporate reputation and silent endurance constitute boundary conditions of the relationship between service failure-related customer anger and revenge intentions.

Design/methodology/approach

In line with past service failure research, the authors test the hypotheses using a scenario-based online experiment with 243 participants.

Findings

This research reaffirms the positive relationship between anger and revenge intentions and finds support for the hypothesized boundary conditions; customers with better corporate reputation perceptions and higher levels of silent endurance express weaker revenge intentions than those with poor corporate reputation perceptions and lower levels of silent endurance.

Originality/value

This research offers unique insights into how service organizations can buffer the detrimental effects of service failure-induced customer anger.
Modelling techno-sectoral innovation system
Authors: Azad Sayyed Mohsen , Khodabakhsh Pouria , Roshannafas Fatemeh , Ghodsypour Seyed Hassan
Published: June 2019

Purpose

This study aims to scrutiny the performance of the petrochemical sector and the technological innovation life cycle. Also, the stage of the innovation life cycle for the sector is specified. Then, scenarios are designed to improve the speed of the sector development. For this reason, for synchronizing the petrochemical sector, this study tries to combine two innovation systems (technological and sectoral systems) called “techno-sectoral innovation system” under an integrated model. Furthermore, the “functions and driving motors” are expanded in the proposed model.

Design/methodology/approach

By combining two concepts of the innovation systems, the complexity of the system rises to some extent. Also, to model causal relationships in the sector and non-linear connections between variables, system dynamics approach is applied. During this phase, the flow diagram of the model is translated to a simulation programme using Vensim software. Model validation is investigated using a comparison of the actual with simulated values.

Findings

The results predict the functions state of the innovation system and detect activation of innovation motors in each stage of the innovation life cycle. Validation shows the acceptable error of the indices. It can be concluded that the sector is relatively in the development state. Four scenarios have been proposed for representing policies that sector uses to motivate its companies. The best scenario is the fourth one that divides resources with different weightings among companies to accelerate switching time between sector’s motors. Finally, the fourth scenario can improve the performance of the petrochemical.

Originality/value

The hybrid approach shows researchers that performance of an industry can be improved based on sectoral and technological at the same time. Thus, this case-based model can contribute to other researchers, as a base model. Also, it could be customized with parameters and the relationship between players and functions. Furthermore, a dynamic switch among the motors has been presented in the model.
Flow and heat transfer of non-Newtonian power-law fluids over a stretching surface with variable thermal conductivity
Authors: Yang Meng , Lin Yanhai
Published: June 2019

Purpose

The purpose of this paper is to investigate the flow and heat transfer of power-law fluids over a non-linearly stretching sheet with non-Newtonian power-law stretching features.

Design/methodology/approach

The governing non-linear partial differential equations are reduced to a series of ordinary differential equations by suitable similarity transformations and the numerical solutions are obtained by the shooting method.

Findings

As the temperature power-law index or the power-law number of the fluids increases, the dimensionless stream function, dimensionless velocity and dimensionless temperature decrease, while the velocity boundary layer and temperature boundary layer become thinner for other fixed physical parameters. The thermal diffusivity varying as a function of the temperature gradient can be used to present the characteristics of flow and heat transfer of non-Newtonian power-law fluids.

Originality/value

Unlike classical works, the effect of power-law viscosity on the temperature field is considered by assuming that the temperature field is similar to the velocity field with modified Fourier’s law heat conduction for power-law fluid media.
A description of four science-based corporate GHG target-setting methods
Authors: Faria Pedro Cabral Santiago , Labutong Nicole
Published: June 2019

Purpose

Amidst a growing interest in greenhouse gas (GHG) science-based target setting by businesses, it is becoming increasingly urgent to understand how these are set in theory and in practice.

Design/methodology/approach

Using a model framework for science-based methods, the authors compare four different science-based target-setting methods: sectoral decarbonization approach, linear emission reduction to target year, GHG emissions per unit of value added and corporate finance approach to climate stabilizing targets. Input and output variables, GHG scopes, allocation principles and mathematical formulations are described, followed by a discussion of the differences and similarities between methods.

Findings

The authors show GHG emission mitigation scenarios are as important in the determination of targets as the allocation principle.

Practical implications

For this reason, businesses should apply well-bellow 2ºC scenarios with robust sectoral and regional granularity and the science community should consider the needs of these groups of stakeholders.

Social implications

Policymakers should actively support efforts by corporations to set science-based targets and ensure that the research they commission can be translated into practical action by non-party stakeholders.

Originality/value

This paper contributes to the understanding of the theory and practice of science-based targets.
Social innovation and service delivery in Belgium and South Africa
Authors: Biljohn Maréve Inge , Lues Liezel
Published: June 2019

Purpose

Social innovation (SI) remains a latent area in the South African local government (LG) sphere despite its growing use in public-sector service delivery globally. This paper aims to investigate the use of SI in the service delivery of LG through a comparison between the City of Ghent (CoG) (Belgium) and the Mangaung Metropolitan Municipality (MMM) (South Africa).

Design/methodology/approach

Through a comparative case study approach, qualitative research methods were used to both collect and analyze the data. Data collection instruments included document analysis (naturally occurring data), semi-structured interviews (generated data) and focus group discussions (generated data).

Findings

Although LG is obliged to collaborate with citizens, various factors influence citizens’ ability to make contributions, even when platforms are created. Collaborative initiatives aid in the realization of collective development visions and enhance citizen participation in a more responsive and inclusive approach to service delivery. Collaborations would require citizens and LG officials to be empowered by finding new ways of working together, as well as developing skills.

Practical implications

Citizens’ participation when SI is used to enhance service delivery should be meticulously planned. Co-producing services require a conducive internal organizational context that advances citizen participation in the governance and decision-making of service delivery, which is likewise optimal for enhancing the use of SI during the respective co-production service delivery stages. Achieving a conducive internal organizational context is influenced by the role of LG officials and politicians in understanding the value proposition of participation in service delivery to citizens. This value proposition is crucial to building and establishing a trust relationship between citizens, LG officials and politicians. Finally, consensus concerning the concept of SI and its use and implementation is important to ensure its consistent use and application by a municipality, and thus calls for further in-depth investigation.

Originality/value

SI is a nascent area for which the discourse is still under development, and it is a concept that is often the subject of debate in literature. This paper is justified by the fact that the use of SI in the South African LG sphere lags behind the growing use thereof in public-sector service delivery by LGs globally. In addition, the study presents novel insights regarding similarities and differences in the use of SI through a comparison between two LGs, namely, the MMM and the CoG.
Molecular microbial ecology of stable versus failing rice straw anaerobic digesters
Authors: Zealand Andrew M. , Mei Ran , Roskilly Anthony P. , Liu WenTso , Graham David W.
Published: June 2019

Waste rice straw (RS) is generated in massive quantities around the world and is often burned, creating greenhouse gas and air quality problems. Anaerobic digestion (AD) may be a better option for RS management, but RS is presumed to be comparatively refractory under anaerobic conditions without pre‐treatment or co‐substrates. However, this presumption assumes frequent reactor feeding regimes but less frequent feeding may be better for RS due to slow hydrolysis rates. Here, we assess how feeding frequency (FF) and organic loading rate (OLR) impacts microbial communities and biogas production in RS AD reactors. Using 16S rDNA amplicon sequencing and bioinformatics, microbial communities from five bench‐scale bioreactors were characterized. At low OLR (1.0 g VS l−1 day−1), infrequently fed units (once every 21 days) had higher specific biogas yields than more frequent feeding (five in 7 days), although microbial community diversities were statistically similar (P > 0.05; ANOVA with Tukey comparison). In contrast, an increase in OLR to 2.0 g VS l−1 day−1 significantly changed Archaeal and fermenting Eubacterial sub‐communities and the least frequency fed reactors failed. ‘Stable’ reactors were dominated by Methanobacterium, Methanosarcina and diverse Bacteroidetes, whereas ‘failed’ reactors saw shifts towards Clostridia and Christensenellaceae among fermenters and reduced methanogen abundances. Overall, OLR impacted RS AD microbial communities more than FF. However, combining infrequent feeding and lower OLRs may be better for RS AD because of higher specific yields.