bluuebunny/crossref_metadata_2025 huggingface dataset:
Long read metagenomics, the next step?
Authors: Haro-Moreno Jose M. , López-Pérez Mario , Rodríguez-Valera Francisco
Published: November 2020

Background

Third-generation sequencing has penetrated little in metagenomics due to the high error rate and dependence for assembly on short-read designed bioinformatics. However, 2nd generation sequencing metagenomics (mostly Illumina) suffers from limitations, particularly in allowing assembly of microbes with high microdiversity or retrieving the flexible (adaptive) compartment of prokaryotic genomes.

Results

Here we have used different 3rd generation techniques to study the metagenome of a well-known marine sample from the mixed epipelagic water column of the winter Mediterranean. We have compared Oxford Nanopore and PacBio last generation technologies with the classical approach using Illumina short reads followed by assembly. PacBio Sequel II CCS appears particularly suitable for cellular metagenomics due to its low error rate. Long reads allow efficient direct retrieval of complete genes (473M/Tb) and operons before assembly, facilitating annotation and compensates the limitations of short reads or short-read assemblies. MetaSPAdes was the most appropriate assembly program when used in combination with short reads. The assemblies of the long reads allow also the reconstruction of much more complete metagenome-assembled genomes, even from microbes with high microdiversity. The flexible genome of reconstructed MAGs is much more complete and allows rescuing more adaptive genes.

Conclusions

For most applications of metagenomics, from community structure analysis to ecosystem functioning, long-reads should be applied whenever possible. Particularly for in-silico screening of biotechnologically useful genes, or population genomics, long-read metagenomics appears presently as a very fruitful approach and can be used from raw reads, before a computing-demanding (and potentially artefactual) assembly step.
Non-Invasive Plasma Glycomic and Metabolic Biomarkers of Post-treatment Control of HIV
Authors: Giron Leila B. , Palmer Clovis S. , Liu Qin , Yin Xiangfan , Papasavvas Emmanouil , Damra Mohammad , Goldman Aaron R. , Tang Hsin-Yao , Johnston Rowena , Mounzer Karam , Kostman Jay R. , Tebas Pablo , Landay Alan , Montaner Luis J. , Jacobson Jeffrey M. , Li Jonathan Z. , Abdel-Mohsen Mohamed
Published: November 2020

Non-invasive biomarkers that predict HIV remission after antiretroviral therapy (ART) interruption are urgently needed. Such biomarkers can improve the safety of analytic treatment interruption (ATI) and provide mechanistic insights into the pathways involved in post-ART HIV control. We identified plasma glycomic and metabolic signatures of time-to-viral-rebound and probability-of-viral-rebound using samples from two independent cohorts. These samples include a large number of post-treatment controllers, a rare population demonstrating sustained virologic suppression after ART-cessation. The signatures remained significant after adjusting for key demographic and clinical confounders. We also confirmed a mechanistic link between biomarkers and HIV latency reactivation and myeloid inflammationin vitro. Finally, machine learning algorithms selected sets of biomarkers that predict time-to-viral-rebound with 74-76% capacity and probability-of-viral-rebound with 97.5% capacity. In summary, we fill a major gap in HIV cure research by identifying non-invasive biomarkers, with potential functional significance, that predict duration and probability of viral remission after treatment interruption.
In vitroevaluation of the response of human tendon-derived stromal cells to a novel electrospun suture for tendon repair
Authors: Nezhentsev A , Abhari RE , Baldwin MJ , Mimpen JY , Augustyniak E , Isaacs M , Mouthuy P-A , Carr AJ , Snelling SJB
Published: November 2020

Recurrent tears after surgical tendon repair remain common. Repair failures can be partly attributed to the use of sutures not designed for the tendon cellular niche nor for the promotion of repair processes. Synthetic electrospun materials can mechanically support the tendon whilst providing topographical cues that regulate cell behaviour. Here, a novel electrospun suture made from twisted polydioxanone (PDO) polymer filaments is compared to PDS II, a clinically-used PDO suture currently utilised in tendon repair. We evaluated the ability of these sutures to support the attachment and proliferation of human tendon-derived stromal cells using PrestoBlue and Scanning Electron Microscopy. Suture surface chemistry was analysed using X-ray Photoelectron Spectroscopy. Bulk RNA-Seq interrogated the transcriptional response of primary tendon-derived stromal cells to sutures after 14 days. Electrospun suture showed increased initial cell attachment and a stronger transcriptional response compared to PDS II, with relative enrichment of pathways including mTorc1 signalling and depletion of epithelial mesenchymal transition. Neither suture induced transcriptional upregulation of inflammatory pathways compared to baseline. Twisted electrospun sutures therefore show promise in improving outcomes in surgical tendon repair by allowing increased cell attachment whilst maintaining an appropriate tissue response.
BMP signaling: at the gate between activated melanocyte stem cells and differentiation
Authors: Infarinato Nicole R. , Stewart Katherine S. , Yang Yihao , Gomez Nicholas C. , Pasolli H. Amalia , Hidalgo Lynette , Polak Lisa , Carroll Thomas S. , Fuchs Elaine
Published: November 2020

Through recurrent bouts synchronous with the hair cycle, quiescent melanocyte stem cells (McSCs) become activated to generate proliferative progeny that differentiate into pigment-producing melanocytes. The signaling factors orchestrating these events remain incompletely understood. Here, we use single-cell RNA sequencing with comparative gene expression analysis to elucidate the transcriptional dynamics of McSCs through quiescence, activation, and melanocyte maturation. Unearthing converging signs of increased WNT and BMP signaling along this progression, we endeavored to understand how these pathways are integrated. Employing conditional lineage-specific genetic ablation studies in mice, we found that loss of BMP signaling in the lineage leads to hair graying due to a block in melanocyte maturation. We show that interestingly, BMP signaling functions downstream from activated McSCs and maintains WNT effector, transcription factor LEF1. Employing pseudotime analysis, genetics, and chromatin landscaping, we show that following WNT-mediated activation of McSCs, BMP and WNT pathways collaborate to trigger the commitment of proliferative progeny by fueling LEF1- and MITF-dependent differentiation. Our findings shed light upon the signaling interplay and timing of cues that orchestrate melanocyte lineage progression in the hair follicle and underscore a key role for BMP signaling in driving complete differentiation.
FGF signaling regulates development by processes beyond canonical pathways
Authors: Ray Ayan T. , Mazot Pierre , Brewer J. Richard , Catela Catarina , Dinsmore Colin J. , Soriano Philippe
Published: November 2020

FGFs are key developmental regulators that engage a signal transduction cascade through receptor tyrosine kinases, prominently engaging ERK1/2 but also other pathways. However, it remains unknown whether all FGF activities depend on this canonical signal transduction cascade. To address this question, we generated allelic series of knock-in Fgfr1 and Fgfr2 mouse strains, carrying point mutations that disrupt binding of signaling effectors, and a kinase dead allele of Fgfr2 that broadly phenocopies the null mutant. When interrogated in cranial neural crest cells, we identified discrete functions for signaling pathways in specific craniofacial contexts, but point mutations, even when combined, failed to recapitulate the single or double null mutant phenotypes. Furthermore, the signaling mutations abrogated established FGF-induced signal transduction pathways, yet FGF functions such as cell–matrix and cell–cell adhesion remained unaffected, though these activities did require FGFR kinase activity. Our studies establish combinatorial roles of Fgfr1 and Fgfr2 in development and uncouple novel FGFR kinase-dependent cell adhesion properties from canonical intracellular signaling.
The intergenerational effect of parental enthusiasm for reading
Authors: Clavel Jose G. , Mediavilla Mauro
Published: November 2020

Purpose

This paper aims to focus on how reading for pleasure is transmitted within the family. Using data taken from the Programme for International Student Assessment test of 2009, which dealt in depth with the reading proficiency of students, the authors show that children of parents who read for pleasure are better readers. Within the extensive research and published results on reading performance, the authors focused on the transmission of parents’ reading attitudes to their children.

Design/methodology/approach

In this study, the authors have opted for an approach of “difference in differences”, applied to a population that represents all 15-year-olds from five countries (Germany, Denmark, Hungary, Italy and Portugal). To support this study, the authors chose as a response variable the difference between reading performance and maths performance of each student, taking into account five plausible values for each student. The authors have several explanatory variables, among them what we call the “treatment”, which is the parents’ enthusiasm for reading.

Findings

The calculated estimations clearly indicate that there is a positive effect for four out of the five countries analysed, ranging from 4 points for Italy to 6.5 points for Germany and Portugal. As for the significance of the effect, with the exception of Hungary, the result is reliable and robust. It should also be noted that the variable that indicates the existence of a reading habit by children (daily reading for pleasure) is seen as a factor that positively affects the difference between competence in reading and mathematics in four out of the five countries analysed.

Originality value

The results show positive effects on children whose parents read for pleasure, and this fact should be used to further encourage parents to promote their own reading time for pleasure. In view of the already quantified trend in international reports that adults are reading less, it seems crucial to involve educational authorities in reversing this phenomenon, knowing the impact that adult reading habits have on the reading competence of young people.
Developing a model to identify the antecedents and consequences of user satisfaction with digital libraries
Authors: Soltani-Nejad Nima , Taheri-Azad Fatemeh , Zarei-Maram Nayereh , Saberi Mohammad Karim
Published: November 2020

Purpose

The primary objective of the present study was to design and develop a model to identify the antecedents and consequences of user satisfaction with digital libraries.

Design/methodology/approach

The theoretical framework of this study was based on information system success theory, technology acceptance model (TAM), media affinity theory, satisfaction-loyalty theory and engagement theory. In so doing, eight hypothesized relationships were formulated to develop the conceptual model. The study approach was quantitative. Using simple random sampling technique, a total of 409 Iranian students participated in the study and responded to the survey. Descriptive and inferential data analysis was also performed using SPSS and SmartPLS3 software.

Findings

The results showed that the generic usability of digital library and the quality of digital resources could be used as a functional theoretical framework to predict and understand the factors contributing to user satisfaction in the domain of digital library. Increasing user satisfaction with digital library may have implications including recommending the digital library to others, the digital library reusing as well as the digital library engaging and integrating with them. It should be noted that system quality, service quality, and information quality are important factors in the formation of perceived usefulness, perceived ease of use, and digital libraries' affinity.

Originality/value

This study is the first attempt to empirically evaluate the antecedents and consequences of the user satisfaction with digital library presenting a new model. The model presented in this study can be used in future research as well. Also, this study has eloquently expanded the theories of user satisfaction with digital libraries.
How cyber political brands emerge: a socio-material analysis of the Italian Five Star movement and the Czech pirate party
Authors: Lucarelli Andrea , Fuschillo Gregorio , Chytkova Zuzana
Published: November 2020

Purpose

Although information technology has been at the centre of attention of political branding for some time, research has traditionally focused mainly on its role in the facilitation of communication. This paper aims to unpack the role of information technology in the emergence of new cyber political brands.

Design/methodology/approach

This research uses a dual case study approach that focuses on the relationship between branding, politics and information technology. The analysis focuses on two successful political cyber brands: the Italian Five Star Movement and the Czech Pirate Party. Data collection covering the time frame between their emergence and their political success occurs through netnographic methods.

Findings

Cyber political brands emerge and materialize in different forms. The present analysis allows for a delineation of three conceptual elements that characterize the constitutive interrelationship of information technology in the emergence of cyber political brands. The first conceptual element, organization, refers to how political brands become structured around linked activities. The second conceptual element, orientation, describes how the activities of a political brand are directed to build a specific path and legitimize courses of action. The third conceptual element, operation, delineates the processes that anchor and stabilize the political brands in its “own” culture, establishing specific base activities.

Research limitations/implications

Information technology and the techno-culture emerging around the two cyber party brands can be seen as the possible delineations of new “cleavages” in the form of “information technology-culture” which enables potential electoral success.

Originality/value

The present study by offering the conceptualization of the cyber political brand shows how political brands can reflect a type of performative cultural branding where they become able, as a networked-medium, to assemble a specific techno-culture. In terms of political brand development, the current analysis offers a framework that allows us to consider the process of political party development in a new fashion.
Teacher Fellow accreditation – a madrigal of voices! But is it the right tune? Tensions of standardisation, engagement and neoliberalism
Authors: Kershaw-Solomon Hazel , Beech Nick , Gold Jeff , Claxton Julia , Auty Tricia , Beech Susan
Published: November 2020

Purpose

The purpose of this paper is to explore the impact competency frameworks as standardisation can have on the employee engagement of academic staff within higher education (HE) through their employment as managerial tools.

Design/methodology/approach

A literature review is conducted from which the conditions for effective competency frameworks are evaluated and the influence of changes in the HE environment in the form of political agendas and tight resources are explored.

Findings

This paper provides insights into the dynamics of public service modernisation and the tensions between the dominant discourse of managerialism and the degree of agency afforded to professional academics. It highlights the relevance of informal peer relationships in setting the climate to generate collegial bonding and professional engagement that underpin successful teacher fellowship accreditations. It further highlights the key role managers play in this process and provides a conceptual framework highlighting the dynamics and combined effect of employee engagement and competency frameworks set within complex HE environment.

Practical implications

This paper brings together the prerequisites for effective implementation of competency frameworks to implement successful employee engagement strategies set within the complexities of the HE context, which has not been studied to date. Armed with such insights, Human Resource Development (HRD) departments and universities can implement competency assessments that generate greater staff engagement.

Originality/value

The paper provides a critical approach in reviewing the impact of Continued Professional Development and its link to professional status and thus helps British Universities and others to understand how the mechanisms at work affect engagement levels of academic staff. Armed with this depth of understanding of how the change initiative works, with whom and under what circumstances, universities will be better able to meet target UK Professional Standards Framework membership levels required by the higher education academy (HEA) and, subsequently, the HEA to meet their targets for the government.
The benefits and challenges of a blended peer mentoring program for women peer mentors in science, technology, engineering and mathematics (STEM)
Authors: Rockinson-Szapkiw Amanda , Wendt Jillian L.
Published: November 2020

Purpose

The unequitable representation among genders in science, technology, engineering and mathematics (STEM) degrees and careers remains a persisting challenge. Peer mentoring has been cited as one method for supporting women and racial and ethnic minorities in becoming interested in, experiencing self-efficacy in and persisting in STEM. The current study was undertaken to explore how and in what ways peer mentors' participation in the program (namely, the mentoring experience) influenced their STEM self-efficacy beliefs, interests, skills and behaviors, including their intent to persist and actual persistence in STEM.

Design/methodology/approach

Using a multisite case study design, the current study implemented a blended peer mentoring program at two historically black institutions.

Findings

The experience in the peer mentoring process increased mentors' self-efficacy, career interest, perceived mentoring skill development in most areas and intent to persist in STEM. Evidence from the interviews and open-ended survey questions demonstrated that the peer mentoring experience had a direct influence on the mentor's self-efficacy, career interest, leadership and professional skills and persistence. The thematic analysis of the data sources revealed that specific elements of the peer mentoring experience influenced mentors' beliefs, interests, skills and behaviors, including recognition, functioning as a mentor, developing an other's orientation, engaging in a sisterhood and developing competencies.

Originality/value

Findings support the benefit of the blended peer mentoring program model among women who identify as a racial or ethnic minority across two historically black college or universities (HBCUs). Peer mentoring programs should include training to increase competencies and skills, should provide resources targeted to specific mentor needs and should include opportunities for self-reflection and components of faculty support.
An integrated AHP and ISO14000, ISO26000 based approach for improving sustainability in supply chains
Authors: Talib Faisal , K Josaiman Saheim , Faisal Mohd. Nishat
Published: November 2020

Purpose

Typically, adoption of sustainability in organizations are often done in an unstructured way without the consideration of other partners in the supply chain. The purpose of this paper is to suggest a coherent plan to improve sustainability in the supply chains utilizing ISO standards for environment and social responsibility.

Design/methodology/approach

This paper draws on literature on ISO14000 and ISO26000 to derive a set of variables applicable to supply chains, which are then prioritized for real organizations utilizing analytic hierarchy process.

Findings

The findings highlight that not all the variables of environmental, social and economic responsibility are equally important. Besides, the work reported in this paper justifies the application of multi-criteria decision-making (AHP) to prioritize elements of sustainability in context supply chains. The suggested method is illustrated using inputs from large manufacturing companies in Qatar.

Practical implications

ISO14000 and ISO26000 are well known standards; however, there was no effort to integrate these standards to improve sustainability in supply chains. The suggested methodology provides invaluable help to the managers to implement sustainability in a coherent manner across the supply chain.

Originality/value

The research contributes to the extant literature by proposing a new methodology based on the integration of three-approaches: Analytic Hierarchy Process, ISO14000 and ISO26000 systems.
Designing an advanced system for destination management: a case study of Northern Indiana
Authors: Choe Yeongbae , Fesenmaier Daniel R.
Published: November 2020

Purpose

The purpose of this paper is to describe the core of an advanced destination management system, which uses a series of data matching techniques and business analytics.

Design/methodology/approach

This study first proposes the conceptual framework for an advanced destination management system and then illustrates the core components of the proposed system using real-world data from Northern Indiana. In this study, search interests, devices used and other forms of website use derived from online clickstream data were merged with visitor demographic and tripographic information obtained from an online survey to develop an analytic model used to describe the core market structure.

Findings

Key demographic factors (e.g. gender, age and income), search interests, referred websites, the number of total sessions, temporal aspects and spatial aspects of visitor travel provide essential information defining the structure and dynamics of the visitor marketing in Northern Indiana.

Originality/value

The process and data used in this study provide a “proof of concept” for developing highly personalized marketing systems, which can substantially improve the competitiveness of a destination management organization.
Competing and cooperating globally: how firms’ multimarket contact relates to joint price elevation in coopetition networks
Authors: Chiao Yu-Ching , Lin Chun-Chien , Huang Chun-Ju
Published: November 2020

Purpose

This study aims to draw attention to the familiarity effect among international multimarket contact (MMC) firms on coopetition in the global container shipping industry and to better understand the contingency model of structural holes and in-degree centrality on joint price elevation actions and subsequent performance.

Design/methodology/approach

Drawing on competitive dynamics and the literature on networks, a panel data model is developed from 6,489 competitive and 7,146 cooperative actions of the top 21 shipping firms in 18 global arenas with a structured content analysis method being applied.

Findings

Stronger MMC by firms requires increased levels of cooperative actions to elevate prices. This coopetition relationship is enhanced or weakened when the focal firm occupies a higher level of structural hole or position of competitive in-degree centrality.

Practical implications

Shipping liners seeking to cooperate with joint action in oligopolistic markets are offered guidelines and strategies to increase their performance through their actions.

Originality/value

This study contributes to the literature on coopetition networks by further analyzing interfirm relationships and interactions that enhance performance, while exploring network positioning strategies to mitigate risks.
Pre-exposure prophylaxis uptake for HIV infection prevention among young men who have sex with men and transgender women in Bangkok, Thailand
Authors: Auemaneekul Naruemon , Lertpruek Sirirat , Satitvipawee Pratana , Tuah Nik AA
Published: November 2020

Purpose

The purpose of this study aimed to assess factors associated with the intention to take pre-exposure prophylaxis (PrEP) among Thai young men who have sex with men (YMSM) and transgender women (TGW) in Bangkok.

Design/methodology/approach

The study surveyed 350 sexually active Thai YMSM and TGW aged between 18 and 24 years registered with a nongovernmental organization (NGO) working with the MSM community. Data were collected using snowball sampling from four venues. Participants completed a self-administered questionnaire. Logistic regression was used to evaluate factors associated with the intention to take PrEP daily.

Findings

The results showed that of all those surveyed, n = 310 (88%) participated. The median age was 21 years. In all, 18% of participants had heard about PrEP, and 36% correctly identified that PrEP is used for prevention. After receiving information, 31% intended to take daily PrEP and the Voluntary Counseling and Testing (VCT) rate was 35.5%. Factors significantly associated with intention to take daily PrEP were history of HIV testing (adjusted odds ratio (AOR), 2.3, 95% CI, 1.3–4.1), and high perceived behavioral control of PrEP adherence scores (AOR 3.0, 95% CI, 1.8–5.2).

Originality/value

This study showed that intention to take and knowledge of daily PrEP among YMSM and TGW was low. Promoting health education to YMSM and TGW about PrEP and MSM-friendly VCT services are needed to effectively implement PrEP in HIV prevention programs.
Developing a Muslim tourism market: the perspective of travel agencies
Authors: Hsu Po-Yi , Ku Edward C.S. , Lai Tzu-Ching , Hsu Shih–Chieh
Published: November 2020

Purpose

This study investigated how customer orientation and relationships influenced relational benefits via employees' attitudes toward travel agencies and partnership management.

Design/methodology/approach

Survey questionnaires were mailed to experts of travel agencies in Taiwan. The hypothesis of this study was tested and used a research model characterized by the SEM-PLS approach.

Findings

The findings of this study indicate that the travel service involves a wide range of firms, regardless of internal or external partner management, and to develop the Muslim tourism market sustainability.

Research limitations/implications

From a theoretical perspective, it was found that customer orientation of travel agencies and relationship selling among travel agencies affects partnership management of travel agencies and their employees' attitudes, which were positively associated with the relational benefit of travel agencies.

Practical implications

Travel agencies must maintain continuous collaborative relationships to ensure the sustainable development of the Muslim tourism market.

Originality/value

This study provides a meaningful model for investigating the trend and tourism products of the Muslim tourism market regarding collaboration between travel agencies and partners.
The effectiveness of passive land value capture mechanisms in funding infrastructure
Authors: Lee Chyi Lin , Locke Martin
Published: November 2020

Purpose

This study examines the effectiveness of passive value capture mechanisms as an effective form of mechanisms in funding infrastructure from an Australian perspective. The lukewarm response of active value capture mechanisms such as betterment levies in Australia is also discussed.

Design/methodology/approach

A case study of the Sydney Metro City and Southwest (SMCSW) project in Sydney is used to illustrate passive value capture mechanisms.

Findings

Unlike many developed countries, passive value capture mechanisms have been adopted in Australia. This approach is an effective form of value capture mechanisms to capture the value uplift to offset the total development cost of the SMCSW project. However, this approach is highly sensitive to property transaction activities that could be affected by the general economic conditions and unprecedented events such as the COVID-19 pandemic. Further, there is a widespread discussion of the efficiency of land tax in New South Wales (NSW) in capturing all properties subject to the value uplift. Consequently, a shift towards a broad-based land tax is recommended in which it would provide a more efficient way of infrastructure funding.

Practical implications

Policymakers should consider a broad-based land tax for residential and commercial properties in order to improve the efficiency of passive value capture mechanisms. This also highlights property valuers should play a greater role in the development of broad-based land tax system.

Originality/value

Previous studies have extensively demonstrated property value impacts of transit investments; very little research assesses the growth of value capture funding mechanisms, particularly passive value capture mechanisms. Specifically, this paper is the first paper to assess the effectiveness of passive value capture mechanisms.
Favoritism or equality: difference analysis of users' utilization of academic social networks for top research corporations
Authors: Yan Weiwei , Liu Qian , Chen Ruoyu , Zhang Min
Published: November 2020

Purpose

As an important platform for academic communication and knowledge acquisition, academic social network (ASN) has attracted worldwide researchers. The purpose of this paper is to examine and compare the differences of corporation researchers in ASN utilization from the two aspects of social performance and academic performance.

Design/methodology/approach

Applying knowledge-based theory, this paper decoupled ASN into social network and academic network and measured utilization of users by social performance and academic performance. Hypotheses were proposed from the perspectives of research areas and corporate reputation. In the part of empirical research, the top 92 research corporations were selected as the sample, and relevant metric data from the member profile pages on ResearchGate was collected for comparing analysis to explore their utilization characteristics.

Findings

The results show that users of different research corporations have certain favoritism in their utilization of ASNs. Science and technology-oriented corporations are better in comprehensive social performance and academic quality. Science-oriented corporations are better at utilizing the interactive functions. However, neither social utilization nor academic utilization, technology-oriented corporations perform well.

Originality/value

This paper focuses on corporation researchers, who have started to embrace ASNs but whose behaviors were less studied. The research paradigm is an expansion and enrichment of the dual network decoupling theory in the field of ASN research. It also deepens the research on ASN utilization of corporation researchers and could give references for ASNs to improve service for corporation users in different research areas.

Peer review

The peer review history for this article is available at:https://publons.com/publon/10.1108/OIR-12-2019-0389
Usability effectiveness of a federated search system for electronic theses and dissertations in Nigerian institutional repositories
Authors: Salau Sadiat Adetoro , Abifarin F.P. , Alhassan J.A. , Udoudoh S.J.
Published: November 2020

Purpose

The purpose of this study was to evaluate the usability effectiveness of a webware for electronic theses and dissertations (ETDs) in Nigerian repositories. The webware (etdsearch.com.ng) is a web application system that curates ETDs from three sampled Federal government-owned universities. The system also links users to the repositories where the theses and dissertations are hosted.

Design/methodology/approach

The case study research strategy was adopted for the study. Sixty postgraduate students from three universities were randomly selected. A usability evaluation questionnaire based on the ISO 9241-11 framework was used to collect data after performing pre-defined queries/tasks based on the informational and transactional query models. The research questions were analysed using the median of the performance score (fx) of the three universities for each item evaluated, while the Kruskall–Wallis test by ranks was used to test the null hypothesis at a 5% level of significance.

Findings

The study answered two research questions and tested two null hypotheses on the usability effectiveness of the webware based on the informational and transactional queries. The participants found the ETD search system effectively useable. In addition, there was no significant difference in the opinions of the participants.

Research limitations/implications

The webware used simulated repositories as a feed bed for the ETDs in order to have control over the workability of the repositories. Thus, the results may differ slightly when “live” repositories are used.

Practical implications

The effectiveness of a webware that aggregates ETDs in Nigerian repositories will present libraries in Nigeria with evidence on how these systems work and can be improved upon.

Originality/value

There is a dearth of literature on practical usability studies of digital information systems in Nigerian libraries.
UV curable flame retardant coating: a novel synthetic approach of trispiperazido phosphate based reactive diluent
Authors: Mali Pundalik Pandharinath , Pawar Nilesh S. , Sonawane Narendra S. , Patil Vikas , Patil Rahul
Published: November 2020

Purpose

The purpose of this work was to develop a new trispiperazido phosphate-based reactive diluent (diphosphate-piperazine hydroxyl acrylate [DPHA]) and used as a flame retardant with an epoxy acrylate (EA) in ultraviolet (UV)-curable wood coating.

Design/methodology/approach

The concentration of reactive diluent was varied from 0% to 20% in the UV-curable formulation with constant photoinitiator concentration. The effect of DPHA concentration on film properties was studied by differential scanning calorimetry and thermogravimetric analysis, gel content, water absorption and limiting oxygen index.

Findings

The results showed that the viscosity of the prepared formulation decreased by increasing reactive diluent (DPHA) concentration which leads to improving the coating efficiency. A high concentration of reactive diluent (DPHA) of the cured films shows good resistance against stain, mechanical and thermal properties, which results in an increased glass transition temperature (Tg) and cross-linking density of the films.

Originality/value

The new trispiperazido phosphate-based reactive diluent was used in wood coating formulation, which resulted in excellent flame-retardant properties with higher cross-linked density with good stain resistance. This material can provide a wide range of application for coating industries to produce a glossy finish.
Effect of steam autoclaving on laser sintered polyamide 12
Authors: Wingham James Robert , Omran Maha , Shepherd Joanna , Majewski Candice
Published: November 2020

Purpose

The use of laser sintering (LS) in the medical sector has increased dramatically in recent years. With the move towards direct use of these parts in clinical applications, there is a greater need to understand the effects of standard processes on the part properties. The purpose of this study is to determine the effect that steam sterilisation has on the mechanical properties of LS polyamide 12 parts.

Design/methodology/approach

The research presented here focusses on the effect of a single steam sterilisation cycle on the mechanical properties of polyamide 12 parts manufactured using LS. The influence of water content on the properties was investigated, with additional drying steps trialled to establish the potential to reverse any changes observed and to determine their root cause.

Findings

The results show that steam sterilisation has a significant effect on the mechanical properties of LS polyamide 12 parts, with a 39% reduction in elastic modulus, a 13% decrease in ultimate tensile strength and a 64% increase in the elongation at break. These properties were also all found to correlate with the water content, suggesting that this was the cause of the difference. The original properties of the parts were able to be recovered after oven drying.

Practical implications

These results show that with an additional drying step, LS polyamide 12 parts can be steam sterilised with no effect on the mechanical properties.

Originality/value

This is believed to be the first investigation into the effects of steam sterilisation in isolation on LS polyamide 12 parts, the first instance of drying parts to recover mechanical properties and the first instance of multiple water content measurements being directly linked to the mechanical properties.
Disentangling the roles of bottom‐up and top‐down drivers in the trade‐off between food acquisition and safety in prey with multiple predators
Authors: Pays Olivier , Blanchard Pierrick , Chamaillé‐Jammes Simon , Valeix Marion , Loveridge Andrew J. , Macdonald David W. , Périquet Stéphanie , van der Meer Esther , Duncan Patrick , Mtare Godfrey , Fritz Hervé
Published: November 2020

Prey face a trade‐off between acquiring food and avoiding predation, but food availability, and therefore its effect, is rarely measured in field studies investigating non‐lethal effects of predation. The main aim of this study was to investigate the role of the presence of predators in the functional adjustments of feeding parameters with patch quality in a medium‐sized herbivore.

In Hwange National Park (Zimbabwe), we set up an experiment by manipulating, over two years, patch quality for impala Aepyceros melampus, a medium‐sized herbivore. We assess predation risk by monitoring the presence of three GPS‐equipped predators: African lions Panthera leo, spotted hyaenas Crocuta crocuta and African wild dogs Lycaon pictus.

In enriched, fertilised plots the impalas reduced step rates (i.e. the rates of change in feeding stations), and increased their number of bites per feeding station while bite rates were not affected. Thus, the main adjustment of their feeding was the step rate. The total time the impalas spent vigilant appeared to be a good predictor of the variation of their bite rate. Although vigilance caused a reduction in bite rate when at a feeding station, the impalas reduced the relative costs of vigilance by continuing chewing and processing their food when scanning for predators.

When predators were in the vicinity, the impalas increased their exclusive vigilance (high‐cost vigilance) but not their vigilance while chewing (low‐cost vigilance) and decreased their bite rate while their step rate and the number of bites per feeding station did not change significantly. The impalas were thus visually disconnected from their patch, and reduced their bite rate when actually foraging. Exclusive vigilance increased when both lions and hyaenas were in the vicinity, and when wild dogs were nearby.

Patterns of vigilance that altered bite rate were linked to the presence of predators during the previous 24 hr. Over the long term patch quality was the main determinant of the feeding parameters (step rate and bite rate). This study shows how predators, by affecting the time prey devote to predator detection, shape the functional adjustments of food acquisition by prey to local patch quality.

A free Plain Language Summary can be found within the Supporting Information of this article.
Dopamine receptor D2 inhibition alleviates diabetic hepatic stellate cells fibrosis by regulating the TGF‐β1/Smads and NFκB pathways
Authors: Zhao Bingbing , Li Siwei , Guo Zuoming , Chen Zhe , Zhang Xinying , Xu Changqing , Chen Junting , Wei Can
Published: November 2020

Diabetic hepatic fibrosis (DHF) is a progressive liver disease and a chronic complication of diabetes mellitus. The main cause of DHF is the activation of quiescent hepatic stellate cells (HSCs) by high glucose stimulation. Dopamine receptor D2 (DRD2)‐mediated dopamine signalling can be involved in the regulation of diabetic liver disease, but the exact role of DRD2 in DHF is still poorly understood. This study aimed to investigate the protective effect of DRD2 inhibition on diabetic liver fibrosis and the potential mechanism. We established both streptozotocin (STZ)‐induced type 1 diabetes (T1D, fed for 20 weeks) rat model and high glucose (HG, 40 mmol/L)‐stimulated HSCs model. The results from both the rats with STZ and the HSCs treated with HG showed increased expression of DRD2, NOX‐5, inflammation‐related proteins (IL‐6 and TNFα) and fibrosis‐related proteins (TGF‐β1, CO‐Ⅰ/Ⅲ/ IV, MMP‐2/9 and fibronectin). In vivo, the serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total antioxidant capacity (T‐AOC) levels were significantly increased, and hematoxylin‐eosin (HE) staining, Masson staining, and electron microscopy revealed liver lesions and hepatocyte injury. In addition, HG‐treated HSCs exhibited altered oxidative stress ‐ related indexes, including superoxide dismutase (SOD), malondialdehyde (MDA) and reactive oxygen species (ROS), changed and abnormally proliferated in vitro. TGF‐β1, the phosphorylated Smad2, nuclear NFκB‐p65, phosphorylated NFκB‐p65 and phosphorylated IκBα were also increased. Interestingly, haloperidol (DRD2 inhibitor) and n‐acetyl‐L‐cysteine (NAC, an active oxygen scavenger) reduced the above‐mentioned changes. In conclusion, DRD2 inhibition can reduce diabetic HSCs oxidative damage and fibrotic proliferation partly via the TGF‐β1/Smads and NFκB pathways.
Textural Insights on Significance of Ophiolitic Chromitites, with Special Reference to Oman
Authors: NICOLAS Adolphe , BOUDIER Françoise
Published: November 2020

Based on the textural and crystallographic study of four chromitite sites in the Oman ophiolite, we show that chromite crystallized in situ at Moho transition zone, where exposed as podiform chromitite deposits.

Crystallization operated either by crystal fractionation in a mini‐magma chamber (Tuf dyke), or more commonly by melt‐rock reaction of a hydrated Cr‐rich melt and enclosing dunite. Oxidizing conditions at Moho level triggered the crystallization of chromite at the expense of the corroded olivine network. High‐temperature mantle flow (1100–1200 °C), recorded in the joined reacting olivine aggregates, constrains the timing of chromitite formation.

Models of genesis of chromitite deposits must account for a hydrous component initiating partial melting of refractory peridotite, and the revealed occurrence of ultra‐high‐pressure cratonic phases included in some chromite crystals of some ophiolitic chromitites.
Metallogeny of Serpentinite‐hosted Magnetite Deposits: Hydrothermal Overgrowth on Chromite or Metamorphic Transformation of Chromite?
Authors: ESLAMI Alireza , KANANIAN Ali , GRIECO Giovanni , GATTA G. Diego , ROTIROTI Nicola
Published: November 2020

Peculiar and rare occurrences of serpentinite‐hosted magnetite deposits with mineable sizes are found in the Mesozoic ophiolites of Greece (Skyros), Iran (Nain and Sabzevar) and Oman (Aniba). These deposits have diverse thickness (from a few centimeters up to 50 m) and length (2 to >500 m). Magnetite ores show variable textures, including massive, nodular and banded ores, veins, net and fine‐grained disseminations in serpentinites. Intriguingly, the investigated magnetite deposits can be mistaken for chromitite pods. Serpentinite‐hosted magnetite deposits show three modes of occurrences including: (i) boulders strewn across the serpentinites (i.e. Skyros Island); (ii) ore bodies along the nonconformity contacts between serpentinites and limestones (i.e. Aniba); (iii) irregular and discontinuous trails of massive and semi‐massive ore bodies within highly sheared serpentinite masses (i.e. Nain; Sabzevar). In all of these magnetite ore bodies, relicts of chromian spinel grains are occasionally enclosed in magnetite crystals. The chemistry of Cr‐spinel relics found in these magnetite bodies are comparable to those of accessory Cr‐spinels in the surrounding serpentinized peridotites. BSE images and elemental mapping revealed that magnetite occurs as a nucleation on chromian spinels but not being involved in reaction either with chromite or ferritchromite. Low‐grade metamorphic transformation of chromite into Fe‐chromite is documented along the cracks and fractures of a few chromite grains. Generally, magnetite has typical hydrothermal compositions, characterized by low Cr, V and Ti and high Mg and Mn. It is crucial to note that a few magnetite grains with metamorphic origin are characterized by high Cr and low Ti and Ni. The potential source of iron is essentially the Fe‐rich olivine. We believe that multi‐episodic serpentinization of peridotite systems at high fluid‐rock ratios is the main process responsible for precipitation of magnetite at ore levels whereas low‐grade metamorphic transformation of chromite to magnetite has minor contribution. Cumulative factors in generation of these deposits are modal volume of mantle olivine, peridotite composition, fluid chemistry, fluid‐rock ratio, mechanisms of transportation and precipitation, structural controls such as cracks and shear zones.
Early Paleozoic Ocean in the North Qaidam: Constraints from Kaipinggou Ophiolite
Authors: CHEN Danling , ZHU Xiaohui , REN Yunfei , TUO Yu
Published: November 2020

The North Qaidam orogenic belt (NQOB) lies at the northeast margin of Tibet Plateau, between the Qilian massif to the north and Qaidam massif to the south. It consists of predominantly gneisses and marbles with minor eclogite and garnet peridotite, and is known as an Early Paleozoic continental deep subduction ultrahigh pressure (UHP) metamorphic belt in northwest China. Recently some studies suggest that the NQOB experienced oceanic deep subduction prior to the continental deep subduction. However, the records of ocean events are rarely preserved because of the complex multi‐stage transformation. Therefore, whether the Early Paleozoic ocean exists and the formation, nature and evolution of the Early Paleozoic ocean in North Qaidam are still in controversies.

In this contribution, we report a new discovered SSZ‐type ophiolite suite in Kaipinggou area, the western segment of the NQOB. The ophiolite is mainly composed of peridotite, gabbro, basalt, boninite, andesitic porphyrite and plagiogranite. In which, the basalt and homogeneous gabbro are both enriched in LILE and depleted in HFSE, and display flat or LREE‐depleted REE patterns, similar to the MORB‐like geochemical characteristics of fore‐arc basalts; the boninite exhibits characteristics of fore‐arc boninites with high Si and Mg, but low Ti and Ca contents; the andesitic porphyrite is enriched in LILE but depleted in HFSE, similar to island arc magmatic rocks. Rock assemblage and their geochemical characteristics suggest that this SSZ‐type ophiolite was formed in fore‐arc setting of intra‐oceanic arc. The plagiogranite is a low‐potassium tholeiite metaluminous granite with low trace elements contents, slight enrichment of LREE, depletion of HREE and positive Eu anomaly; combining with ∊Hf (t) values (13.8–17.1) of zircons, the plagiogranite could be originated from partial melting of gabbros. LA–ICP–MS zircon U–Pb dating yielded the crystallization ages of 535±2 Ma, 513±3 Ma and 510±3 Ma for two cumulate gabbros and one homogeneous gabbro, respectively, and a formation age of 492±8 Ma for the plagiogranite.

All these data suggest the existence of an Early Paleozoic ocean in the North Qaidam, and the initial subduction of the oceanic slab occurred earlier than 535Ma.