bluuebunny/crossref_metadata_2025 huggingface dataset:
Small Molecule Induced Toxic Human-IAPP Species Characterized by NMR
Authors: Cox Sarah J. , Rodriguez Camargo Diana C. , Lee Young-Ho , Ivanova Magdalena I. , Padmini Vediappen , Reif Bernd , Ramamoorthy Ayyalusamy
Published: November 2019

In this study, the effect of CurDAc, a water-soluble curcumin derivative, on the formation and stability of amyloid fibers is revealed. CurDAc interaction with amyloid is structurally selective which is reflected in a strong interference with hIAPP aggregation, while showing weaker interactions with human-calcitonin and Amyloid-β1-40 in comparison. Remarkably, CurDAc also exhibited potent fiber disaggregation for hIAPP generating a toxic oligomeric species.
Micro-pellet culture reveals that bone marrow mesenchymal stromal cell (BMSC) chondrogenic induction is triggered by a single day of TGF-β1 exposure
Authors: Futrega Kathryn , Robey Pamela G. , Klein Travis J. , Crawford Ross W. , Doran Michael R.
Published: November 2019

Despite immense promise, engineering of stable cartilage tissue from bone marrow-derived stromal cells (BMSCs, also known as bone marrow-derived “mesenchymal stem cells”) remains elusive. Relative cartilage-like matrix deposition is commonly used to guide BMSC chondrogenic optimisation efforts. However, matrix deposition is heterogeneous in most models, and notably, it lags behind cell fate decisions. We reason that the lag time between cell fate decision and matrix accumulation, coupled with matrix heterogeneity, has obscured basic BMSC biological characteristics, such as differentiation kinetics. Here, we utilize a customized microwell platform to assemble hundreds of small-diameter BMSCmicro-pellets and characterized chondrogenic differentiation kinetics in response to the canonical signaling molecule, transforming growth factor-β1 (TGF-β1).Micro-pellets provide a homogeneous readout, and our experimental design accounts for the significant time delay between growth factor signal and deposition of cartilage-like matrix. While 14-to-21-day induction protocols are routine, BMSCmicro-pellet cultures reveal that a single day of TGF-β1 exposure was sufficient to trigger chondrogenic differentiation cascades resulting in outcomes similar tomicro-pellets exposed to TGF-β1 for 21 days. RNA-sequencing analysis demonstrated that one day of TGF-β1 exposure was also sufficient to induce hypertrophic cascades in BMSC, not observed in articular chondrocytes. Refocusing chondrogenic induction optimisation efforts from weeks to the first hours or days of culture, using homogeneous model systems, may benefit efforts to build stable cartilage formed by BMSCs.

Significance

Themacro-pellet model, and assumptions generated using it, have permeated BMSC-based cartilage tissue engineering strategies since the 1990s. Using amicro-pellet model, we show that BMSC chondrogenic kinetics are significantly more rapid than historicalmacro-pellets data suggests, and that BMSC chondrogenic and hypertrophic commitment is instructed by a single day of TGF-β1 exposure. This highly relevant study demonstrates that: (1)macro-pellets, which are large heterogeneous tissue models confound the differentiation kinetics visible inmicro-pellet models; (2) induction strategies should focus on the first hours or days of culture; (3) even a single day of TGF-β1 exposure drives BMSC to form hypertrophic tissuein vivo, requiring early intervention to prevent hypertrophy; and (4) articular chondrocytes and BMSCs respond distinctly to TGF-β1.
Latent factor modelling of scRNA-seq data uncovers novel pathways dysregulated in cell subsets of autoimmune disease patients
Authors: Palla Giovanni , Ferrero Enrico
Published: November 2019

Latent factor modelling applied to single-cell RNA-sequencing (scRNA-seq) data is a useful approach to discover gene signatures associated with cell states. However, it is often unclear what method is best suited for specific tasks and how latent factors should be interpreted from a biological perspective.

Here, we compare four state-of-the-art methods and explore their stability, predictive power and coverage of known biology. We then propose an approach that leverages the derived latent factors to directly assign pathway activities to specific cell subsets. By applying this framework to scRNA-seq datasets from biopsies of rheumatoid arthritis and systemic lupus erythematosus patients, we discover both known and novel disease-relevant gene signatures in specific cellular subsets in a fully unsupervised way. Focusing on rheumatoid arthritis, we identify an inflammatory Oncostatin M receptor signalling signature active in a subset of synovial fibroblasts and dysregulation of the GAS6 - MERTK axis in a subset of synovial monocytes with efferocytic function.

Overall, we provide insights into strengths and weaknesses of latent factors models for the analysis of scRNA-seq data, we develop a framework to identify cell subtypes in a function- or phenotype-driven way and use it to identify novel pathways dysregulated in rheumatoid arthritis.
Cholesterol binding to the sterol-sensing region of Niemann Pick C1 protein confines dynamics of its N-terminal domain
Authors: Dubey Vikas , Bozorg Behruz , Wüstner Daniel , Khandelia Himanshu
Published: November 2019

Lysosomal accumulation of cholesterol is a hallmark of Niemann Pick type C (NPC) disease caused by mutations primarily in the lysosomal membrane protein NPC1. NPC1 contains a transmembrane sterol sensing domain (SSD), which is supposed to regulate protein activity upon cholesterol binding, but the mechanisms underlying this process are poorly understood. Using atomistic simulations, we show that the binding of cholesterol to the SSD of NPC1 suppresses conformational dynamics of the luminal domains which otherwise bring the luminal N-terminal domain (NTD) closer to the lipid bilayer. The presence of an additional 20% membrane cholesterol has negligible impact on this process. We propose that cholesterol acts as an allosteric effector, and the modulation of NTD dynamics by the SSD-bound cholesterol constitutes an allosteric feedback mechanism in NPC1 which controls cholesterol abundance in the lysosomal membrane.
BRD4 Prevents R-Loop Formation and Transcription-Replication Conflicts by Ensuring Efficient Transcription Elongation
Authors: Edwards Drake , Maganti Rohin , Tanksley Jarred P. , Luo Jie , Park James J.H. , Balkanska-Sinclair Elena , Ling Jinjie , Floyd Scott R.
Published: November 2019

Effective spatio-temporal control of transcription and replication during S-phase is paramount to maintaining genomic integrity and cell survival. Dysregulation of these systems can lead to conflicts between the transcription and replication machinery causing DNA damage and cell death. BRD4, a BET bromodomain protein and known transcriptional regulator, interacts with P-TEFb to ensure efficient transcriptional elongation by stimulating phosphorylation of RNA Polymerase II (RNAPII). Here we report that disruption of BET bromodomain protein function causes RNAPII pausing on the chromatin and DNA damage affecting cells in S-phase. We find that this persistent, RNAPII-dependent pausing leads to accumulation of RNA:DNA hybrids (R-loops), which are known to lead to transcription-replication conflicts (TRCs), DNA damage, and cell death. Furthermore, we show that resolution of R-loops abrogates BET bromodomain inhibitor-induced DNA damage, and that BET bromodomain inhibition induces both R-loops and DNA damage at sites of BRD4 occupancy. Finally, we see that the BRD4 C-terminal domain, which interacts with P-TEFb, is required to prevent R-loop formation and DNA damage caused by BET bromodomain inhibition and that oncogenes which promote transcription and replication exacerbate BET bromodomain inhibitor-induced DNA damage. Together, these findings demonstrate that BET bromodomain inhibitors can damage DNA via induction of R-loops and TRCs in highly replicative cells.
Tau-tubulin kinase 1 and amyloid-β peptide induce phosphorylation of collapsin response mediator protein-2 and enhance neurite degeneration in Alzheimer disease mouse models
Authors: Ikezu Seiko , Ingraham Dixie Kaitlin L. , Koro Lacin , Watanabe Takashi , Kaibuchi Kozo , Ikezu Tsuneya
Published: November 2019

The accumulation of phosphorylated tau protein (pTau) in the entorhinal cortex (EC) is the earliest tau pathology in Alzheimer’s disease (AD). Tau tubulin kinase-1 (TTBK1) is a neuron-specific tau kinase and expressed in the EC and hippocampal regions in both human and mouse brains. Here we report that collapsin response mediator protein-2 (CRMP2), a critical mediator of growth cone collapse, is a new downstream target of TTBK1 and is accumulated in the EC region of early stage AD brains. TTBK1 transgenic mice show severe axonal degeneration in the perforant path, which is exacerbated by crossing with Tg2576 mice expressing Swedish familial AD mutant of amyloid precursor protein (APP). TTBK1 mice show accumulation of phosphorylated CRMP2 (pCRMP2), in the EC at 10 months of age, whereas age-matched APP/TTBK1 bigenic mice show pCRMP2 accumulation in both the EC and hippocampal regions. Amyloid-β peptide (Aβ) and TTBK1 suppresses the kinetics of microtubule polymerization and TTBK1 reduces the neurite length of primary cultured neurons in Rho kinase-dependent manner in vitro. Silencing of TTBK1 or expression of dominant-negative Rho kinase demonstrates that Aβ induces CRMP2 phosphorylation at threonine 514 in a TTBK1-dependent manner, and TTBK1 enhances Aβ-induced CRMP2 phosphorylation in Rho kinase-dependent manner in vitro. Furthermore, TTBK1 expression induces pCRMP2 complex formation with pTau in vitro, which is enhanced upon Aβ stimulation in vitro. Finally, pCRMP2 forms a complex with pTau in the EC tissue of TTBK1 mice in vivo, which is exacerbated in both the EC and hippocampal tissues in APP/TTBK1 mice. These results suggest that TTBK1 and Aβ synergistically induce phosphorylation of CRMP2, which may be causative for the neurite degeneration and somal accumulation of pTau in the EC neurons, indicating critical involvement of TTBK1 and pCRMP2 in the early AD pathology.
Genomic patterns of introgression in interspecific populations created by crossing wheat with its wild relative
Authors: Nyine Moses , Adhikari Elina , Clinesmith Marshall , Jordan Katherine W. , Fritz Allan K. , Akhunov Eduard
Published: November 2019

Introgression from wild relatives is a valuable source of novel allelic diversity for breeding. We investigated the genomic patterns of introgression fromAegilops tauschii, the diploid ancestor of the wheat D genome, into winter wheat (Triticum aestivum) cultivars. The population of 351 BC1F3:5lines was selected based on phenology from crosses between six hexaploid wheat lines and 21 wheat-Ae. tauschiioctoploids. SNP markers developed for this population and a diverse panel of 116Ae. tauschiiaccessions by complexity-reduced genome sequencing were used to detect introgression based on the identity-by-descent analysis. Overall, introgression frequency positively correlated with recombination rate, with a high incidence of introgression at the ends of chromosomes and low in the pericentromeric regions, and was negatively related to sequence divergence between the parental genomes. Reduced introgression in the pericentromeric low-recombining regions spans nearly 2/3 of each chromosome arm, suggestive of the polygenic nature of introgression barriers that could be associated with multilocus negative epistasis between the alleles of wild and cultivated wheat. On the contrary, negative selection against the wild allele ofTg, controlling free-threshing trait and located in the high-recombining chromosomal region, led to reduced introgression only within ∼10 Mbp region aroundTg. These results are consistent with the effect of selection on linked variation described by the Hill-Robertson effect, and offer insights into the introgression population development for crop imrpovement to ensure retention of introgressed diversity across entire genome.
Persistence of a novel regeneration-associated transitional cell state in pulmonary fibrosis
Authors: Kobayashi Yoshihiko , Tata Aleksandra , Konkimalla Arvind , Katsura Hiroaki , Lee Rebecca F. , Ou Jianhong , Banovich Nicholas E. , Kropski Jonathan A. , Tata Purushothama Rao
Published: November 2019

Stem cell senescence is often seen as an age associated pathological state in which cells acquire an abnormal and irreversible state. Here, we show that alveolar stem cell differentiation during lung regeneration involves a unique previously uncharacterized transitional state that exhibits cardinal features normally associated with cell senescence. Specifically, using organoid cultures, multiple in vivo injury models coupled with single cell transcriptomics and lineage tracing analysis, we find that alveolar stem cell differentiation involves a novel, pre-alveolar type-1 transitional state (PATS) en route to their terminal maturation. PATS can be distinguished based on their unique transcriptional signatures, including enrichment for TP53, TGFβ, and DNA damage repair signaling, and cellular senescence in both in vivo and ex vivo regenerating tissues. Significantly, PATS undergo extensive cell stretching, which makes them vulnerable to DNA damage, a feature commonly associated with most degenerative lung diseases. Importantly, we find enrichment of PATS-like state in human fibrotic lung tissues, suggesting that persistence of such transitional states underlies the pathogenesis of pulmonary fibrosis. Our study thus redefines senescence as a state that can occur as part of a normal tissue maintenance program, and can be derailed in human disease, notably fibrosis.
Systematic localization of Gram-negative bacterial membrane proteins
Authors: Sueki Anna , Stein Frank , Savitski Mikhail , Selkrig Joel , Typas Athanasios
Published: November 2019

The molecular architecture and function of the Gram-negative bacterial cell envelope is dictated by protein composition and localization. Proteins that localize to the inner (IM) and outer (OM) membranes of Gram-negative bacteria play critical and distinct roles in cellular physiology, however, approaches to systematically interrogate their distribution across both membranes and the soluble cell fraction are lacking. We employed multiplexed quantitative mass spectrometry to assess membrane protein localization in a proteome-wide fashion by separating IM and OM vesicles from exponentially growing E. coli K-12 cells on a sucrose density gradient. The migration patterns for >1600 proteins were classified in an unbiased manner, accurately recapitulating decades of knowledge in membrane protein localization in E. coli. For 559 proteins that are currently annotated as peripherally associated to the IM (Orfanoudaki and Economou, 2014) and display potential for dual localization to either the IM or cytoplasm, we could allocate 110 to the IM and 206 as soluble based on their fractionation patterns. In addition, we uncovered 63 cases, in which our data disagreed with current localization annotation in protein databases. For 42 of them, we were able to find supportive evidence for our localization findings in literature. We anticipate our systems-level analysis of the E. coli membrane proteome will serve as a useful reference dataset to query membrane protein localization, as well as provide a novel methodology to rapidly and systematically map membrane protein localization in more poorly characterized Gram-negative species.
Unsupervised Machine Learning for Data Encoding applied to Ovarian Cancer Transcriptomes
Authors: George Tom M , Lio Pietro
Published: November 2019

Machine learning algorithms are revolutionising how information can be extracted from complex and high-dimensional data sets via intelligent compression. For example, unsupervised Autoen-coders train a deep neural network with a low-dimensional “bottlenecked” central layer to reconstruct input vectors. Variational Autoencoders (VAEs) have shown promise at learning meaningful latent spaces for text, image and more recently, gene-expression data. In the latter case they have been shown capable of capturing biologically relevant features such as a patients sex or tumour type. Here we train a VAE on ovarian cancer transcriptomes from The Cancer Genome Atlas and show that, in many cases, the latent spaces learns an encoding predictive of cisplatin chemotherapy resistance. We analyse the effectiveness of such an architecture to a wide range of hyperparameters as well as use a state-of-the-art clustering algorithm, t-SNE, to embed the data in a two-dimensional manifold and visualise the predictive power of the trained latent spaces. By correlating genes to resistance-predictive encodings we are able to extract biological processes likely responsible for platinum resistance. Finally we demonstrate that variational autoencoders can reliably encode gene expression data contaminated with significant amounts of Gaussian and dropout noise, a necessary feature if this technique is to be applicable to other data sets, including those in non-medical fields.
The effect of competition mind-set on persuasion: mediation role of processing style
Authors: Kim Yeung-Jo
Published: November 2019

Purpose

The purpose of this paper is to examine the effect of a competition mind-set on persuasion. Specifically, this research examined the effect of a fit between a competition mind-set and messages on the persuasive effectiveness.

Design/methodology/approach

Participants were randomly assigned to a condition of 2 (competition: competition mind-set vs control) × 2 (message: concrete feasibility vs abstract desirability) between-subjects design.

Findings

This research demonstrated that participants in the competition mind-set (vs control) condition expressed the messages as more persuasive and evaluated the product more favorably when they were exposed to concrete feasibility messages. Furthermore, this effect was mediated by a local processing style.

Originality/value

The present research provides a useful marketing communication strategy. For the effectiveness of messages, concrete feasibility-related merits should be emphasized in competition contexts.
Curbing PPP construction projects’ failure using enhanced stakeholder management success in developing countries
Authors: Eyiah-Botwe Emmanuel , Aigbavboa Clinton O. , Thwala Wellington Didibhuku
Published: November 2019

Purpose

Globally, inadequate resources, skills deficiency and poor infrastructure have necessitated public-private partnerships (PPPs) as investment initiative for public sector projects. The purpose of this paper is to evaluate the key constructs for improved stakeholder management (SM) success in curbing PPP projects’ failure in developing countries to fill the research gap. Pre-stakeholder identification (PSI); implementation, monitoring and feedback (IMF) factors impact on PPP projects’ success in Ghana were examined.

Design/methodology/approach

In total, 16 models were studied as part of literature review followed by a qualitative three-round Delphi survey for SM key factors and validated using a quantitative questionnaire survey. The findings were analysed using structural equation modelling and a model fit test.

Findings

PSI, IMF factors directly influence PPP SM success model hence are key constructs. Furthermore, stakeholder consideration, a clear statement of objectives, adopting design and build are variables established as influencing PPP projects failures. Stakeholder identification, engagement, communication and analysis are generic factors.

Practical implications

Project managers can achieve stakeholder satisfaction and improve PPP projects delivery by considering the innovative PPP SM model. Furthermore, considering the identified factors and variables in holistic models will enhance stakeholder involvement thereby curbing PPP projects failure.

Social implications

Reducing PPP projects’ failure will enhance socio-economic growth.

Originality/value

PSI; IMF factors have never been included in holistic PPP SM model. They are proposed to curb PPP projects’ failure.
Predicting adolescents’ behavioural intentions in adulterated food management
Authors: Kim Yunhwa
Published: November 2019

Purpose

The purpose of this paper is to determine the function of adulterated food management (AFM) in the behavioural intentions of adolescents on food safety concerns.

Design/methodology/approach

The methodology is exploratory in nature and uses analysis of variance and regression in determining the predictive power of the independent variables (AFM’s mediator variables) on the dependent variables (food safety concern and AFM behaviour intention). For this, a survey was conducted on middle and high school students in South Korea using a five-point Likert scale.

Findings

Perceived beliefs on, and competency and behavioural intention in, AFM significantly differed depending on food safety concern level (p<0.01). When perceived beliefs and competencies of AFM were regressed against behavioural intention, the model was highly significant and showed huge variance (R2=0.65). The factors influencing AFM in behavioural intention differed among all three groups: high concern group (efficacy, attitude and situation management), medium concern group (benefits, efficacy, attitude, situation management and hygiene practices) and low concern group (benefits, barriers and situation management). Therefore, AFM education should be observed with emphasis on varying points depending on the level of food safety concern.

Research limitations/implications

As this study only focused on exploring probable predictors for the criterion (perceived food safety concern), the contributions of each mediator factor to the full model are not covered in this study. Future investigations can include the study of individual variables and residuals to remove biases that may be present in the model.

Originality/value

The study will contribute to the safety of society and the health of adolescents by solving the issue of food safety and the problem of adulterated food in the aspect of the beliefs and competence of adolescents according to their concern level.
BPM and change management
Authors: Binci Daniele , Belisari Sara , Appolloni Andrea
Published: November 2019

Purpose

The purpose of this paper is to focus on the implementation of an ambidexterity strategy in a large Italian Company that works in the energy field. The aim of the study is to understand how contextual ambidexterity has been achieved during a business process management (BPM) approach by describing the main variables that interacted during the project implementation.

Design/methodology/approach

The authors based their study both on primary (direct observation and interviews) and secondary (company manuals, books and procedures) qualitative investigations of BPM approach based on three business process re-engineering (BPR) projects and nine total quality management (TQM) projects, focused on change team behaviors, dynamics and dialogues.

Findings

The authors observed that the implementation of simultaneously radical and incremental change projects has been influenced by the exploration and exploitation activities related to every single TQM and BPR project considered. The findings suggest that the overall project has been influenced by four main underlying variables, which are task specialization and systems interoperability (knowledge transfer), identity and leadership (knowledge conversion) and two output variables (ambiguity and feedback to change), that, by interacting, enable ambidexterity.

Research limitations/implications

BPM is an important option to consider within the ambidexterity theory, being conceptually conceived as an approach in which TQM and BPR actually complement each other. Moreover, the results contextualize the importance of the change management team (CMT) to manage the connections between knowledge creation and refinement, and vice versa, depending particularly on the knowledge conversion process enabled by a flexible team culture. The focus of the study is mainly at the BPR and TQM project level. The authors consider structural ambidexterity and its enabling mechanisms as the framework in which BPM is implemented. Moreover, research limitations are related both to the specificity of the context, a large, highly specialized and mechanistic company and to the qualitative approach that may reduce the generalization of the empirical results.

Practical implications

Managers need to be cognizant and aware both of the BPM techniques, in order to sustain ambidexterity, and of ambiguity and change feedback as variables that enable the effective connection of the different steps of innovation or refinement strategy and, therefore, of ambidexterity. Moreover, the contextual factors such as leadership and people identity should be considered and managed as important variables related to change.

Originality/value

The originality of this paper is related to improving the understanding of how to implement the theoretical concept of ambidexterity in a real world organization, by providing new evidence that highlights the importance of contextual ambidexterity within a structural ambidexterity strategy during a BPM project.
Risk connectedness of selected CESEE stock markets: a spillover index approach
Authors: Škrinjarić Tihana , Šego Boško
Published: November 2019

Purpose

The purpose of this paper is to empirically evaluate risk spillovers between selected CESEE (Central, Eastern and South-Eastern Europe) stock markets in order to evaluate the possibilities of an international diversification of a portfolio.

Design/methodology/approach

The VAR model and the Diebold and Yilmaz (2009, 2012) spillover index are used, with rolling indices estimation over time in order to observe dynamics, which is important for investment strategies. Data are monthly and include selected CESEE stock market indices which were available to the researcher.

Findings

The empirical analysis for the period of January 2012–June 2019 indicates that some country risks were the net emitter of shocks in the system (Slovenia and Czech Republic), whereas some were net receivers (Croatia and Ukraine). The results are robust with respect to changing the length of the rolling window analysis, which means that investors could utilize such an approach in a dynamic portfolio selection.

Research limitations/implications

Observing only selected markets due to data (un)availability.

Practical implications

The paper shows how international investors can utilize the aforementioned methodology in order to make a more detailed analysis of the dynamics of stock markets connectedness so that international portfolios can be rebalanced according to the results and investors’ preferences.

Originality/value

This is the first such research which focuses on CESEE countries, since existing research is focused on more developed stock markets. Moreover, the empirical analysis extends to commenting the pairwise net indices over time, which is important for the dynamic portfolio rebalancing over time.
The impact of audit committee, CEO, and external auditor quality on the quality of financial reporting
Authors: Alzeban Abdulaziz
Published: November 2019

Purpose

This paper aims to explore the influence of corporate governance (CG) components on the quality of financial reporting (QFR). The components investigated are the Audit Committee (AC), CEO and external auditor quality. The study also examines whether the AC mediates the effects of other components of CG on the QFR.

Design/methodology/approach

Data were collected from 386 listed companies in four European countries for the period 2015-2017. The QFR was measured using two proxies, discretionary accruals and accruals quality. Firstly, an OLS regression model was estimated to measure the effects of the three variables investigated on the QFR, and to determine which of these variables had the greatest influence in this relationship. Secondly, several mediation analyses were performed to test whether the AC mediates the effects of the CEO, and external auditor quality on the QFR.

Findings

The findings reveal that each of these three components has a positive impact on the QFR, but that the AC has the greatest effect in this respect. The findings also indicate that the AC mediates the effect of the CEO on the QFR. Alternative tests and different measures for the variables confirm the robustness of the results obtained.

Practical implications

Significant implications are provided for regulators and policy-makers. Findings of the present study help regulators and policymakers to pay more attention to the enforcement of AC policies, and the appointment of AC members. Further, the results are helpful to policy-makers concerned with improving CG, and who need evidence of the role of high QFR in this matter.

Originality/value

The findings provide insights into the effect of CG on QFR, and into the most influential component in this relationship; hence, they make a valuable contribution to the literature. They also contribute to the topic of mediations analysis in CG research, providing additional evidence that the AC mediates the effects of the CEO, and external auditor quality on the QFR.
Two-stage grey cloud clustering model for drought risk assessment
Authors: Luo Dang , Zhang Manman , Zhang Huihui
Published: November 2019

Purpose

The purpose of this paper is to establish a two-stage grey cloud clustering model to assess the drought risk level of 18 prefecture-level cities in Henan Province.

Design/methodology/approach

The clustering process is divided into two stages. In the first stage, grey cloud clustering coefficient vectors are obtained by grey cloud clustering. In the second stage, with the help of the weight kernel clustering function, the general representation of the weight vector group of kernel clustering is given. And a new coefficient vector of kernel clustering that integrates the support factors of the adjacent components was obtained in this stage. The entropy resolution coefficient of grey cloud clustering coefficient vector is set as the demarcation line of the two stages, and a two-stage grey cloud clustering model, which combines grey and randomness, is proposed.

Findings

This paper demonstrates that 18 cities in Henan Province are divided into five categories, which are in accordance with five drought hazard levels. And the rationality and validity of this model is illustrated by comparing with other methods.

Practical implications

This paper provides a practical and effective new method for drought risk assessment and, then, provides theoretical support for the government and production departments to master drought information and formulate disaster prevention and mitigation measures.

Originality/value

The model in this paper not only solves the problem that the result and the rule of individual subjective judgment are always inconsistent owing to not fully considering the randomness of the possibility function, but also solves the problem that it’s difficult to ascertain the attribution of decision objects, when several components of grey clustering coefficient vector tend to be balanced. It provides a new idea for the development of the grey clustering model. The rationality and validity of the model are illustrated by taking 18 cities in Henan Province as examples.
A fine balance? Unwrapping the coexistence of projects and non-projects in the core of the organization
Authors: Nesheim Torstein
Published: November 2019

Purpose

The purpose of this paper is to extend the understanding of projects in permanent organizations. Previous research has captured organizational contexts where either a project logic dominates or projects support recurrent, ongoing operations. Through a case study, the author shows how projects and non-projects coexist over time in the core of the organization in a balanced manner, addressing the specific tensions in such an organization.

Design/methodology/approach

The author has undertaken a case study of the Norwegian Petroleum Directorate. The analysis is based on several types of data: internal reports, descriptions of structure and roles, internal handbooks and other documents from the period 1998–2018; interviews with ten persons in different roles in the organization; and a survey of 190 employees and middle managers (response rate: 84 percent).

Findings

The author finds that the balance of projects and non-project work, work units and rationale has been an institutional and stabile characteristic, rather than a transitory state of a Norwegian state directorate. It is also found that two types of products or set of tasks are reflected in two types of work groups: long-term work groups and project work groups. There is a subjective element regarding whether a new task should be integrated into an existing long-term unit or serve as the basis of creating a new project. The analysis of work organization, leadership and employee perceptions has revealed a number of similarities and differences between the two work contexts: the long-term work groups and the projects. The balance of projects and non-projects is maintained through shared beliefs and the process of allocation of personnel. This balance is threatened through actual practice in the organization.

Research limitations/implications

A case study does not allow for statistical generalizations. The implication of the study is the revelation of a potential research gap “between” a project-based organization (PBO), on the one hand, and a project-supported organization (PSO), on the other hand.

Practical implications

For organizations that combine projects and non-projects in the core, the paper could contribute to the understanding of tensions and the way to handle them, and provide inspiration regarding mechanisms for resource allocation.

Originality/value

This paper identifies and empirically describes an organization where both projects and non-projects are of great importance in the core activities of the firm, thus filling a “gap” between the PBO and PSO. A number of aspects of this organization are analyzed, including how the balance of the two logics has been maintained over the two decades. The study could provide the basis for a number of research questions on the coexistence of and tensions between projects and non-projects in the core of an organization.
Monitoring of EDM parameters to develop tribo-adaptive Ti6Al4V surfaces through accretion of alloyed matrix
Authors: Philip Jibin T. , Kumar Deepak , Joshi S.N. , Mathew Jose , Kuriachen Basil
Published: November 2019

Purpose

Electrical discharge machining (EDM) is well-known for its credibility in the processing of advanced materials, which are electrically conductive. The strenuous effort associated with machining of Ti6Al4V (Ti64) using conventional methods, and its low tribological behavior, present an immediate need to develop solutions to monitor and improve the compatible techniques such as EDM.

Design/methodology/approach

The present work includes following: monitoring the ED process parameters, namely, current (I) and pulse on time (Ton), in controlling the material removal rate and surface roughness (Ra and Sa) for development of tribo-adaptive surfaces; and investigation on the role of oxides pertinent to the tribo-behavior of Ti64 (bare and EDMed) surfaces.

Findings

The tribological behavior of Ti6Al4V surfaces got remarkably improved through ED machining, which points to the credibility of the process to establish itself as a surface alloying technique. The recast layer (RL, alloyed matrix) acted as a protective coating; stable enough to assist the developed tribo-oxides such as TiO and Ti8O15 in rendering improved sliding performance at load = 50 N and speed = 0.838 ms−1.

Originality/value

The surface modification through ED machining was experimentally proven to improve the wear behavior of Ti6Al4V surfaces.
Teacher education of statistics from theory to practice
Authors: Elbehary Samah Gamal Ahmed
Published: November 2019

Purpose

To prepare pre-service mathematics teachers (PSMTs) in Egypt, learning statistics as a subject takes place at the faculty of science, apart from what is going on at the faculty of education. The Organization for Economic Co-operation and Development has highlighted this dilemma as follows; “Pre-service education in Egypt is characterized by a separation of theory from practice, in the belief that student teachers will put it into practice later in schools” (OECD, 2015, p. 120). The purpose of this paper is to propose a microteaching lesson study (MLS) model that bridges the gap between learning free content pedagogies and teaching statistics, consequently, enhances PSMTs’ pedagogical content knowledge.

Design/methodology/approach

The ethnographic approach has been employed, and hence, the national faculty policy guidelines have been revised through Grossman’s (1990) model. Moreover, a focus group of PSMTs’ opinions has been investigated to interpret the aforementioned situation and provide meaningful insights.

Findings

As a result, the MLS model rooted in constructivism theory has been introduced. Furthermore, supported discourse to enhance PSMTs’ pedagogical content knowledge (PCK) of teaching statistics is described.

Originality/value

The MLS model may help to change PSMTs’ perception concerning the gap between theory and practice. Meanwhile, it could be an endeavor to reform PSMTs’ initial views regarding what learning and teaching of statistics look like, through enhancing their PCK of teaching statistics. Furthermore, engaging them in such environments to be a part of the learning community and learn more from the experts is crucial.
Estimation of construction project building cost by back-propagation neural network
Authors: Jiang Qinghua
Published: November 2019

Purpose

Building cost is an important part of construction projects, and its correct estimation has important guiding significance for the follow-up decision-making of construction units.

Design/methodology/approach

This study focused on the application of back-propagation (BP) neural network in the estimation of building cost. First, the influencing factors of building cost were analyzed. Six factors were selected as input of the estimation model. Then, a BP neural network estimation model was established and trained by ten samples.

Findings

According to the experimental results, it was found that the estimation model converged at about 85 times; compared with radial basis function (RBF), the estimation accuracy of the model was higher, and the average error was 5.54 per cent, showing a good reliability in cost estimation.

Originality/value

The results of this study provide a reliable basis for investment decision-making in the construction industry and also contribute to the further application of BP neural network in cost estimation.
Proximity and centrality in inter-organisational collaborations for innovation
Authors: Capone Francesco , Zampi Vincenzo
Published: November 2019

Purpose

The purpose of this paper is to investigate the impact of the different drivers of the establishment of innovation relationships in an aerospace cluster. In particular, the work investigates the impact of the various forms of proximity in the formation of inter-organisational collaborations for innovation.

Design/methodology/approach

The analysis is based on primary data collected through interviews and questionnaires on innovation collaborations, administered to all the firms operating in the aerospace cluster in Tuscany. The work applies social network analysis and Exponential Random Graph Models to analyse the forces that drive inter-organisational collaborations for innovation.

Findings

Results confirm the importance of geographical proximity in the formation of ties in the cluster, but social proximity is one of the main drivers for tie formation. Reciprocity shows that companies develop innovations in a reciprocal way and that most relationships are bidirectional. Triadic closure is also relevant, where the role played by trust and previous relationships is evident. Finally, hierarchy network processes are underlined, where the most central actors of the network are the most popular confirming a processes of preferential attachment. The central organisations gradually are more important, whereas the marginal ones are left in the periphery.

Originality/value

The work presents some novelties. First, it measures the different impacts of the various forms of proximity together with more advanced measures of network analysis. It allows pointing out the relevance of a firm’s network position in clusters and the fact that clusters assume hierarchical structures similar to centre-periphery networks, where most relevant nodes are in the inner core and marginal organisations are relegated.
Design of functional cotton fabric via modified carbon nanotubes
Authors: Xu Jia , Zhang Jing Yu , Xu Jiahan , Chang Yuqi , Shi Feilong , Zhang Zhanzhu , Zhang Huanxia
Published: November 2019

Purpose

One of the intensively developed in recent years new materials are hybrid textiles modified with carbon nanotubes (CNT). In this paper, CNTs was modified by grafting dimethyl phosphite and perfluorohexyl iodine. It was applied to the cotton to obtain the flame-retardant, water-repellent, ultraviolet-resistant and conductive multifunctional fabric.

Design/methodology/approach

The modified CNTs were loaded onto cotton fabric by impregnation and drying. The CNTs-multi was synthesized by grafted dimethyl phosphite and perfluorohexyl chain and applied to the cotton by dipping-drying method. The surface chemistry of functionalized CNTs was characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy (XPS). The combustion properties were evaluated using a microscale combustion calorimeter, match test and TGA analysis. Surface hydrophilicity and hydrophobicity of fabric surface was characterized by static contact angle, and the UV resistance of the fabric was represented by the UPF value.

Findings

Dimethyl phosphite and perfluorohexyl chain were grafted on the surface of CNTs successively. The quantity of each component on the surface of CNTs was calculated according to XPS results. According to miniature combustion calorimeter data, both the value of maximum heat release rate (PHRR) and total heat release (THR) of CNTs -multi/cotton was about 65% lower than that of untreated cotton fabric. The residue after combustion of CNTs -multi/ cotton in the match test was more compact. The electrical conductivity of multi/ cotton is 225.6 kΩ/□, which is better than that of untreated cotton fabric. The UPF value of CNTs-multi/cotton reached 121, which was indicated that the anti-ultraviolet performance of CNTs-multi was greatly improved.

Research limitations/implications

Modifying method to increase the functional component amuount on the CNTs surface still need to be explored, which could increase the hydrophobicity. How to further improve the functional effect and the general synthetic steps will be of great significance to the preparation of multifunctional modified cotton fabric.

Practical implications

This modifying method can be used in any of multifunctional textile preparation process. The UV-resistant and flame retardant cotton fabric was revealed as a sample for use in outdoor sports such as clothes and tents.

Originality/value

To meet the needs of multifunctional cotton fabric, the modification of CNTs with dimethyl phosphite and perfluorohexyl iodine has not been reported. The modified fabric has flame-retardant, UV-resistant conductive and conductive properties.
Environmental change and the evolution of genomes: Transposable elements as translators of phenotypic plasticity into genotypic variability
Authors: Pimpinelli Sergio , Piacentini Lucia
Published: November 2019

Phenotypic plasticity is generally explained as the result of epigenetic mechanisms modifying gene expression in response to changing environmental conditions. However, the biology of transposable elements (TEs) suggests that such elements may also induce differential gene expression by affecting regulatory regions.

We discuss the ecological and evolutionary relevance of epigenetic modifications versus transposon activity, taking into account that epigenetic modifications are generally reversible but that the modifications induced by TEs are stably inherited.

We outline our perspective on the multiple roles played by environmental changes in the context of adaptive evolution. Environmental perturbations can induce phenotypic variations via epigenetic modulation of gene expression and promote, at the same time, genetic variability by triggering bursts of TE activity; finally, they select which genetic variations are most advantageous for survival.

Within this context, the production of environmentally induced advantageous phenotypes by epigenetic mechanisms could represent an immediate process of adaptation followed by TE‐induced genotypic changes that make these phenotypic variants heritable through the germ line. This scenario could lead TEs to play different roles in the function of the time‐scale of ecological variation, such as those related to climatic change in the current context of global change.

In conclusion, we propose that through TE activation, environmental changes can act as inducers of genetic variability, upon which they also act as selective forces, thus triggering rapid evolutionary processes.

A freePlain Language Summarycan be found within the Supporting Information of this article.
Comparative membrane proteomics reveal contrasting adaptation strategies for coastal and oceanic marine Synechococcus cyanobacteria
Authors: Teoh Fallen , Shah Bhumika , Ostrowski Martin , Paulsen Ian
Published: November 2019

Marine cyanobacteria genus Synechococcus are among the most abundant and widespread primary producers in the open ocean. Synechococcus strains belonging to different clades have adapted distinct strategies for growth and survival across a range of marine conditions. Clades I and IV are prevalent in colder, mesotrophic, coastal waters, while clades II and III prefer warm, oligotrophic open oceans. To gain insight into the cellular resources these unicellular organisms invest in adaptation strategies we performed shotgun membrane proteomics of four Synechococcus spp. strains namely CC9311 (clade I), CC9605 (clade II), WH8102 (clade III) and CC9902 (clade IV). Comparative membrane proteomes analysis demonstrated that CC9902 and WH8102 showed high resource allocation for phosphate uptake, accounting for 44% and 38% of overall transporter protein expression of the species. WH8102 showed high expression of the iron uptake ATP‐binding cassette binding protein FutA, suggesting that a high binding affinity for iron is possibly a key adaptation strategy for some strains in oligotrophic ocean environments. One protein annotated as a phosphatase 2c (Sync_2505 and Syncc9902_0387) was highly expressed in the coastal mesotrophic strains CC9311 and CC9902, constituting 14%–16% of total membrane protein, indicating a vital, but undefined function, for strains living in temperate mesotrophic environments.