bluuebunny/crossref_metadata_2025 huggingface dataset:
RNA uridyl transferases TUT4/7 differentially regulate miRNA variants depending on the cancer cell-type
Authors: Medhi Ragini , Price Jonathan , Furlan Giulia , Gorges Beronia , Sapetschnig Alexandra , Miska Eric A.
Published: July 2021

The human terminal uridyl transferases TUT4 and TUT7 (TUT4/7) catalyse additions of uridines at the 3′ end of RNAs such as the precursors of the tumour suppressor miRNA let-7, upon recruitment by the oncoprotein LIN28A. Consequently, let-7 family miRNAs are downregulated. Disruption of this TUT4/7 activity inhibits tumorigenesis and hence targeting TUT4/7 can be a potential anti-cancer therapy. In this study, we investigate TUT4/7-mediated RNA regulation in two cancer cell lines by establishing catalytic knockout models. Upon TUT4/7 mutation, we observe a significant reduction in miRNA uridylation, which results in defects in cancer cell properties such as cell proliferation and migration. With the loss of TUT4/7-mediated miRNA uridylation, the uridylated miRNA variants are replaced by adenylated isomiRs. Changes in miRNA modification profiles are accompanied by deregulation of expression levels in specific cases. Unlike let-7s, most miRNAs do not depend on LIN28A for TUT4/7-mediated regulation. Additionally, we identify TUT4/7-regulated cell-type-specific miRNA clusters and deregulation in their corresponding mRNA targets. Expression levels of miR-200c-3p and miR-141-3p are regulated by TUT4/7 in a cancer cell type specific manner. Subsequently, BCL2 which is a well-established target of miR-200c is upregulated. Therefore, TUT4/7 loss triggers deregulation of miRNA-mRNA networks in a cell-type-specific manner. Understanding of the underlying biology of such cell-type-specific deregulation will be key when targeting TUT4/7 for cancer therapy.

Graphical Abstract

Highlights

⍰ TUT4/7 catalyse 3′ uridylation of most miRNAs

⍰ Loss of uridylated isomiRs leads to the gain of adenylated isomiRs

⍰ TUT4/7-mediated miRNA deregulation and miRNA-mRNA interactions are specific to the cell line type

⍰ Loss of TUT4/7-mediated RNA uridylation inhibits cancer cell function
Pparα and fatty acid oxidation coordinate hepatic transcriptional architecture
Authors: Cavagnini Kyle S , Wolfgang Michael J
Published: July 2021

Fasting requires tight coordination between the metabolism and transcriptional output of hepatocytes to maintain systemic glucose and lipid homeostasis. Genetically-defined deficits in hepatic fatty acid oxidation result in dramatic fasting-induced hepatocyte lipid accumulation and induction of genes for oxidative metabolism, thereby providing a mouse model to interrogate the mechanisms by which the liver senses and transcriptionally responds to fluctuations in lipid levels. While fatty acid oxidation is required for a rise in acetyl-CoA and subsequent lysine acetylation following a fast, changes in histone acetylation (total, H3K9ac, and H3K27ac) associated with transcription do not require fatty acid oxidation. Instead, excess fatty acids prompt induction of lipid catabolic genes largely via ligand-activated Pparα. We observe that active enhancers in fasting mice are enriched for Pparα binding motifs, and that inhibition of hepatic fatty acid oxidation results in elevated enhancer priming and acetylation proximal to Pparα binding sites within regulatory elements largely associated with genes in lipid metabolism. Also, a greater number of Pparα-associated H3K27ac signal changes occur at active enhancers compared to promoters, suggesting a genomic mechanism for Pparα to tune target gene expression levels. Overall, these data demonstrate the requirement for Pparα activation in maintaining transcriptionally permissive hepatic genomic architecture particularly when fatty acid oxidation is limiting.
Custom-made design of metabolite composition inN. benthamianaleaves using CRISPR activators
Authors: Selma S , Sanmartín N , Espinosa-Ruiz A , Gianoglio S , Lopez-Gresa MP , Vázquez-Vilar M , Flors V , Granell A , Orzaez D
Published: July 2021

Transcriptional regulators based on CRISPR architecture expand our ability of reprogramming endogenous gene expression in plants. One of their potential applications is the customization of plant metabolome through the activation of selected enzymes in a given metabolic pathway. Using the previously described multiplexable CRISPR activator dCasEV2.1, we assayed the selective enrichment inNicotiana benthamianaleaves of four different flavonoids, namely naringenin, eriodictyol, kaempferol and quercetin. After careful selection of target genes and guide RNAs combinations, we created successful activation programs for each of the four metabolites, each program activating between three and seven genes, and with individual gene activation levels ranging from 4- to 1500-fold. Metabolic analysis of the flavonoid profiles of each multigene activation program showed a sharp and selective enrichment of the intended metabolites and their glycosylated derivatives. Remarkably, principal component analysis of untargeted metabolic profiles clearly separated samples according to their activation treatment, and hierarchical clustering separated the samples in five groups, corresponding to the expected four highly enriched metabolite groups, plus an un-activated control. These results demonstrate that dCasEV2.1 is a powerful tool for re-routing metabolic fluxes towards the accumulation of metabolites of interest, opening the door for custom-made design of metabolic contents in plants.
Genome mosaicism in field strains of Mycoplasma bovis as footprints of in-host horizontal chromosomal transfer
Authors: García-Galán Ana , Baranowski Eric , Hygonenq Marie-Claude , Walch Mathilda , Croville Guillaume , Citti Christine , De la Fe Christian , Nouvel Laurent-Xavier
Published: July 2021

Horizontal gene transfer was long thought to be marginal in Mollicutes, but the capacity of some of these wall-less bacteria to exchange large chromosomal regions has been recently documented. Mycoplasma chromosomal transfer (MCT) is an unconventional mechanism that relies on the presence of a functional integrative conjugative element (ICE) in at least one partner and involves the horizontal acquisition of small and large chromosomal fragments from any part of the donor genome, which results in progenies composed of an infinitive variety of mosaic genomes. The present study focuses on Mycoplasma bovis, an important pathogen of cattle responsible for major economic losses worldwide. By combining phylogenetic tree reconstructions and detailed comparative genome analyses of 36 isolates collected in Spain (2016-2018) we confirmed the mosaic nature of 16 field isolates and mapped chromosomal transfers exchanged between their hypothetical ancestors. This study provides evidence that MCT can take place in the field, most likely during co-infections by multiple strains. Because mobile genetic elements (MGEs) are classical contributors of genome plasticity, the presence of phages, insertion sequences (ISs) and ICEs was also investigated. Data revealed that these elements are widespread within the M. bovis species and evidenced classical horizontal transfer of phages and ICEs in addition to MCT. These events contribute to wide-genome diversity and reorganization within this species and may have a tremendous impact on diagnostic and disease control.

IMPORTANCE

Mycoplasma bovis is a major pathogen of cattle with significant detrimental economic and animal welfare on cattle rearing worldwide. Understanding the evolution and the adaptative potential of pathogenic mycoplasma species in the natural host is essential to combating them. In this study, we documented the occurrence of mycoplasma chromosomal transfer, an atypical mechanism of horizontal gene transfer, in field isolates of M. bovis that provide new insights into the evolution of this pathogenic species in their natural host. Despite these events are expected to occur at low frequency, their impact is accountable for genome-wide variety and reorganization within M. bovis species, which may compromise both diagnostic and disease control.
Cultural behaviours can be experimentally induced in wild baboons despite constraints on social information transmission
Authors: Carter Alecia J. , Cowlishaw Guy
Published: July 2021

Abstract

The formation of culture in animal societies, including humans, relies on the social transmission of information amongst individuals. This spread depends upon the transmission of social information, or social learning, between individuals. However, not all information spreads. To better understand how constraints at the individual-, dyad- and group-level might influence the formation of culture, we experimentally introduced four innovations (novel behaviours) across three troops of wild chacma baboons (Papio ursinus). At the individual-level, different phenotypic traits constrained individuals’ use of social information about the innovations. At the dyad-level, we found evidence for social reinforcement and directed social learning affecting who learnt and from whom. Group-level characteristics also limited the diffusion of information, which spread more slowly through social networks that showed less mixing across age classes. Nevertheless, despite these multi-level limitations, the four innovations quickly spread through all the social groups in which they were tested, suggesting that the formation of animal cultures can be surprisingly resilient to constraints on information transmission.
Sex-specific association between urinary kisspeptin and pubertal development
Authors: de Freitas Rafaella Sales , França Thiago Fonseca Alves , Pompeia Sabine
Published: July 2021

Kisspeptins are critical neuropeptides for puberty onset and progression, playing a pivotal role in the reactivation of the hypothalamus-pituitary-gonadal axis in late childhood. Despite their importance, little is known as to how kisspeptin peripheral concentrations are related to sexual maturation in humans, specially using non-invasive measures that allow more widespread testing. Using a cross-sectional design, we investigated whether peripheral kisspeptin concentrations, measured by enzyme-linked immunosorbent assays (ELISA) in two-hour retention midstream urine, are associated with developmental markers in 209 (120 girls) typically developing, 9 to 15-year-olds. Developmental variables were age, self-reported pubertal status using the Pubertal Development Scale, and saliva concentrations of hormones that indicate gonadal (testosterone) and adrenal (dehydroepiandrosterone sulfate) functioning. We found marked sexual differences in urine kisspeptins (controlled for body mass index and socioeconomic status). While concentrations were similar in both sexes until the age of around 12 years, in males there was a positive linear correlation with all developmental measures thereafter, while in girls, kisspeptin concentrations did not change. Of note, our results are in line with those of previous studies using more invasive methods (e.g. blood samples), which indicates that kisspeptin concentrations from two-hour retention midstream urine have potential in exploring sex-specific peripheral action of these peptides.
Mutation rate and spectrum inCaenorhabditis elegansmutation accumulation lines subjected to RNAi-induced knockdown of the mismatch repair genemsh-2
Authors: Katju Vaishali , Konrad Anke , Deiss Thaddeus C. , Bergthorsson Ulfar
Published: July 2021

DNA mismatch repair (MMR), an evolutionarily conserved repair pathway shared by prokaryotic and eukaryotic species alike, influences molecular evolution by detecting and correcting mismatches that escape DNA polymerase proofreading, thereby protecting genetic fidelity, reducing the mutational load, and preventing lethality. Herein we conduct the first genome-wide evaluation of the alterations to the mutation rate and spectrum under impaired activity of theMutSαhomolog,msh-2, inCaenorhabditis elegans. We performed mutation accumulation (MA) under RNAi-induced knockdown ofmsh-2for 50 generations in obligately outcrossingfog-2(lf)lines, followed by next-generation sequencing of 19 MA lines and the ancestral control.msh-2impairment substantially increased the frequency of nuclear base substitutions (∼23×) and small indels (∼328×) relative to wildtype. However, we observed no increase in the mutation rates of mtDNA, and copy-number changes of single-copy genes. There was a marked increase in copy-number variation of rDNA genes under MMR impairment. InC. elegans,msh-2repairs transitions more efficiently than transversions as well as increases the AT mutational bias relative to wildtype. The local sequence context, including sequence complexity, G+C-content, and flanking bases influenced the mutation rate. The X chromosome had a lower substitution and higher indel rate than autosomes, which can either result from sex-specific mutation rates or a nonrandom distribution of mutable sites in the genome. Comparison of MMR impairment inC. elegansto that in other species shows that the specificity of the MMR varies between taxa, and is more efficient in detecting and repairing small indels in eukaryotes relative to prokaryotes.
C25-modified rifamycin derivatives with improved activity againstMycobacterium abscessus
Authors: Paulowski Laura , Beckham Katherine S. H. , Johansen Matt D. , Berneking Laura , Van Nhi , Degefu Yonatan , Staack Sonja , Sotomayor Flor Vasquez , Asar Lucia , Rohde Holger , Aldridge Bree B. , Aepfelbacher Martin , Parret Annabel , Wilmanns Matthias , Kremer Laurent , Combrink Keith , Maurer Florian P.
Published: July 2021

Infections caused byMycobacterium abscessusare difficult to treat due to its intrinsic resistance to most antibiotics. Formation of biofilms and the capacity ofM. abscessusto survive inside host phagocytes further complicate eradication. Herein, we explored whether addition of a carbamate-linked group at the C25 position of rifamycin SV blocks enzymatic inactivation by ArrMab, an ADP-ribosyltransferase conferring resistance to rifampicin. Unlike rifampicin, 5j, a benzyl piperidine rifamycin derivative with a morpholino substituted C3 position, is not modified by purified ArrMab. Additionally, we show that the ArrMabD82 residue is essential for catalytic activity. Thermal profiling of ArrMabin the presence of 5j, rifampicin or rifabutin shows that 5j does not bind to ArrMab. We found that the activity of 5j is comparable to amikacin againstM. abscessusplanktonic cultures and pellicles. Critically, 5j also exerts potent antimicrobial activity againstM. abscessusin human macrophages and shows synergistic activity with amikacin and azithromycin.
Long-chain lipids facilitate insertion of large nanoparticles into membranes of small unilamellar vesicles
Authors: Adan Marzouq , Lion Morgenstein , Huang-Zhu Carlos A. , Yudovich Shimon , Ayelet Atkins , Asaf Grupi , Van Lehn Reid C. , Shimon Weiss
Published: July 2021

Insertion of hydrophobic nanoparticles into phospholipid bilayers is limited to small particles that can incorporate into the hydrophobic membrane core in between the two lipid leaflets. Incorporation of nanoparticles above this size limit requires development of challenging surface engineering methodologies. In principle, increasing membrane thickness should facilitate incorporation of larger nanoparticles. Here, we explore the effect of incorporating very long phospholipids (C24:1) into small unilamellar vesicles on the membrane insertion efficiency of hydrophobic nanoparticles that are 5-13 nm in diameter. To this end, we improved an existing vesicle preparation protocol and utilized cryogenic electron microscopy imaging to examine the mode of interaction and to evaluate the insertion efficiency of membrane-inserted nanoparticles. We also perform classical, coarse-grained molecular dynamics simulations to identify changes in lipid membrane structural properties that may increase insertion efficiency. Our results indicate that long-chain lipids increase the insertion efficiency by preferentially accumulating near membrane-inserted nanoparticles to reduce the thermodynamically unfavorable disruption of the membrane.
An intestinally secreted host factor promotes microsporidia invasion of C. elegans
Authors: El Jarkass Hala Tamim , Mok Calvin , Schertzberg Michael R. , Fraser Andrew G. , Troemel Emily R. , Reinke Aaron W.
Published: July 2021

Microsporidia are ubiquitous obligate intracellular pathogens of animals. These parasites often infect hosts through an oral route, but little is known about the function of host intestinal proteins that facilitate microsporidia invasion. To identify such factors necessary for infection by Nematocida parisii, a natural microsporidian pathogen of Caenorhabditis elegans, we performed a forward genetic screen to identify mutant animals that have a Fitness Advantage with Nematocida (Fawn). We isolated four fawn mutants that are resistant to Nematocida infection and contain mutations in T14E8.4, which we renamed aaim-1 (Antibacterial and Aids invasion by Microsporidia). Expression of AAIM-1 in the intestine of aaim-1 animals restores N. parisii infectivity and this rescue of infectivity is dependent upon AAIM-1 secretion. N. parisii spores in aaim-1 animals are improperly oriented in the intestinal lumen, leading to reduced levels of parasite invasion. Conversely, aaim-1 mutants display both increased colonization and susceptibility to the bacterial pathogen Pseudomonas aeruginosa and overexpression of AAIM-1 reduces P. aeruginosa colonization. Competitive fitness assays show that aaim-1 mutants are favoured in the presence of N. parisii but disadvantaged on P. aeruginosa compared to wild type animals. Together, this work demonstrates how microsporidia exploits a secreted protein to promote host invasion. Our results also suggest evolutionary trade-offs may exist to optimizing host defense against multiple classes of pathogens.
miR-9aregulates levels of bothrhomboidmRNA and protein in the earlyDrosophila melanogasterembryo
Authors: Gallicchio Lorenzo , Griffiths-Jones Sam , Ronshaugen Matthew
Published: July 2021

MicroRNAs have subtle and combinatorial effects on the expression levels of their targets. Studying the consequences of a single microRNA knockout often proves difficult as many such knockouts exhibit phenotypes only under stress conditions. This has led to the hypothesis that microRNAs frequently act as buffers of noise in gene expression. Observing and understanding buffering effects requires quantitative analysis of microRNA and target expression in single cells. To this end, we have employed single molecule fluorescencein situhybridization, immunofluorescence, and high-resolution confocal microscopy to investigate the effects ofmiR-9aloss on the expression of the serine-protease rhomboid inDrosophila melanogasterearly embryos. Our single-cell quantitative approach shows thatrhomboidmRNA exhibits the same spatial expression pattern in WT andmiR-9aknockout embryos, although the number of mRNA molecules per cell is higher whenmiR-9ais absent. However, the level of rhomboid protein shows a much more dramatic increase in themiR-9aknockout. Specifically, we see accumulation of rhomboid protein inmiR-9amutants by stage 5, much earlier than in WT. The data therefore show thatmiR-9afunctions in the regulation ofrhomboidactivity by both inducing mRNA degradation and inhibiting translation in the blastoderm embryo. Temporal regulation of neural proliferation and differentiation in vertebrates bymiR-9is well-established. We suggest thatmiR-9family microRNAs are conserved regulators of timing in neurogenic processes. This work shows the power of single-cell quantification as an experimental tool to study phenotypic consequences of microRNA mis-regulation.
Sex chromosome gene expression associated with vocal learning following hormonal manipulation in female zebra finches
Authors: Davenport Matthew H. , Choe Ha Na , Matsunami Hiroaki , Jarvis Erich D.
Published: July 2021

Zebra finches are sexually dimorphic vocal learners. Males learn to sing by imitating mature conspecifics, but females do not. Absence of song in females is associated with partial atrophy and apparent repression of several vocal learning brain regions during development. However, atrophy can be prevented and vocal learning retained in females when given early pharmacological estrogen treatment. To screen for candidate drivers of this sexual dimorphism, we performed an unbiased transcriptomic analysis of song learning nuclei specializations relative to the surrounding regions from either sex, treated with vehicle or estrogen until 30 days old when divergence between the sexes becomes anatomically apparent. Analyses of transcriptomes by RNA sequencing identified song nuclei-specialized gene expressed modules associated with sex and estrogen manipulation. Female HVC and Area X gene modules were specialized by estrogen supplementation, exhibiting a subset of the transcriptomic specializations observed in males. Female RA and LMAN specialized modules were less dependent on estrogen. The estrogen-induced gene modules in females were enriched for anatomical development functions and strongly correlated to the expression of several Z sex chromosome genes. We present a hypothesis where reduced dosage and expression of these Z chromosome genes suppresses the full development of the song system and thus song learning behavior, which is partially rescued by estrogen treatment.
Modelling complex population structure usingF-statistics and Principal Component Analysis
Authors: Peter Benjamin M
Published: July 2021

Human genetic diversity is shaped by our complex history. Data-driven methods such as Principal Component Analysis (PCA) are an important population genetic tool to understand this method. Here, I contrast PCA with a set of statistics motivated by trees (F-statistics). Here, I show that these two methods are closely related, and I derive explicit connections between the two approaches. I show thatF-statistics have a simple geometrical interpretation in the context of PCA, and that orthogonal projections are the key concept to establish this link. I illustrate my results on two examples, one of local, and one of global human diversity. In both examples, I find that just using the first few PCs provides good population structure is sparse, and only a few components contribute to most statistics. Based on these results, I develop novel visualizations that allow for investigating specific hypotheses, checking the assumptions of more sophisticated models. My results extendF-statistics to non-discrete populations, moving towards more complete and less biased descriptions of human genetic variation.
In situ imaging of bacterial membrane projections and associated protein complexes using electron cryo-tomography
Authors: Kaplan Mohammed , Chreifi Georges , Metskas Lauren Ann , Liedtke Janine , Wood Cecily R , Oikonomou Catherine M , Nicolas William J , Subramanian Poorna , Zacharoff Lori A , Wang Yuhang , Chang Yi-Wei , Beeby Morgan , Dobro Megan , McBride Mark J , Briegel Ariane , Shaffer Carrie , Jensen Grant J
Published: July 2021

The ability to produce membrane projections in the form of tubular membrane extensions (MEs) and membrane vesicles (MVs) is a widespread phenomenon among bacteria. Despite this, our knowledge of the ultrastructure of these extensions and their associated protein complexes remains limited. Here, we surveyed the ultrastructure and formation of MEs and MVs, and their associated protein complexes, in tens of thousands of electron cryo-tomograms of ∼ 90 bacterial species that we have collected for various projects over the past 15 years (Jensen lab database), in addition to data generated in the Briegel lab. We identified MEs and MVs in 13 species and classified several major ultrastructures: 1) tubes with a uniform diameter (with or without an internal scaffold), 2) tubes with irregular diameter, 3) tubes with a vesicular dilation at their tip, 4) pearling tubes, 5) connected chains of vesicles (with or without neck-like connectors), 6) budding vesicles and nanopods. We also identified several protein complexes associated with these MEs and MVs which were distributed either randomly or exclusively at the tip. These complexes include a secretin-like structure and a novel crown-shaped structure observed primarily in vesicles from lysed cells. In total, this work helps to characterize the diversity of bacterial membrane projections and lays the groundwork for future research in this field.
Development of the Inactivated QazCovid-in Vaccine: Protective Efficacy of the Vaccine in Syrian Hamsters
Authors: Zhugunissov Kuandyk , Zakarya Kunsulu , Khairullin Berik , Orynbayev Mukhit , Abduraimov Yergali , Kassenov Markhabat , Sultankulova Kulyaisan , Kerimbayev Aslan , Nurabayev Sergazy , Myrzhakhmetova Balzhan , Nakhanov Aziz , Nurpeisova Ainur , Chervyakova Olga , Assanzhanova Nurika , Burashev Yerbol , Mambetaliev Muratbay , Azanbekova Moldir , Kopeyev Syrym , Kozhabergenov Nurlan , Issabek Aisha , Tuyskanova Moldir , Kutumbetov Lespek
Published: July 2021

In March 2020, the first cases of human coronavirus infection COVID-19 were registered in Kazakhstan. We isolated the SARS-CoV-2 virus from the clinical material from the patients. Subsequently, a whole virion inactivated candidate vaccine, QazCovid-in, was developed based on this virus. To obtain the vaccine, a virus grown in Vero cell culture was used, which was inactivated with formaldehyde, purified, concentrated, sterilized by filtration, and then sorbed on aluminum hydroxide gel particles. The formula virus and adjuvant in buffer saline solution was used as a vaccine. The safety and protective effectiveness of the developed vaccine was studied on Syrian hamsters. The results of the studies showed the absolute safety of the candidate vaccine on the Syrian hamsters. When studying the protective effectiveness, the developed vaccine with an immunizing dose of 5 mcg/dose of a specific antigen protected animals from wild virus at a dose of 104.5TCID50/ml. The candidate vaccine formed virus-neutralizing antibodies in vaccinated hamsters in titers from 3.3 ± 1.45 log2 to 7.25 ± 0.78 log2, which were retained for 6 months (observation period) in the indicated titers. The candidate vaccine suppressed the replication of the wild virus in the body of vaccinated hamsters, protected against the development of acute pneumonia and ensured 100% survival of the animals. At the same time, no replicative virus was isolated from the lungs of vaccinated animals. At the same time, a virulent virus was isolated from the lungs of unvaccinated animals in relatively high titers, reaching 4.5 ± 0.7 lg TCID50/ml. After challenge infection, 100% of unvaccinated hamsters became ill with clinical signs (stress state, passivity, tousled coat, decreased body temperature and body weight, and the development of acute pneumonia), of which 25 ± 5% were fatal. The findings paved the way for testing the candidate vaccine in humans in clinical trials.
A stochastic fuzzy multi-criteria group decision-making for sustainable vendor selection in Indian petroleum refining sector
Authors: Akhtar Mohammad , Ahmad Md Tanweer
Published: July 2021

Purpose

This paper aims to select key criteria for sustainable vendor assessment and spare-parts supplies in the Indian petroleum refining sector using stochastic fuzzy technique for order of preference by similarity to ideal solution (SFTOPSIS).

Design/methodology/approach

The criteria for sustainable vendor evaluation and selection are identified from the review of the literature and further; it is finalized using the Delphi method. Eight supply chain (SC) experts from the Indian petro refining sector were identified as having more than five years of experience and agreed to participate in this study (known as decision-makers (DM)). Five vendors supplying spare-parts are shortlisted from the market with the discussion and consent of procurement experts from petroleum refineries. Subsequently, criteria and vendors are rated based on relative importance in linguistic terms from the group of eight DMs. As ratings involve uncertainties in the decision-making, the SFTOPSIS method is applied to determine criteria weight and vendor ranking at a distinct significance level (α). The ranking of the vendors is obtained for sustainable supply of spare-parts in the Indian petro refining sector using the SFTOPSIS method.

Findings

The ranking of sustainable vendors is obtained through the integrated application of the fuzzy and stochastic approach to capture the uncertainties in the ratings of DMs. The sensitivity analysis is carried out at distinct confidence limits of a normal distribution to obtain a robust ranking of the vendors. In this paper, a case application of SFTOPSIS in the Indian petro refining sector is presented in which key criteria and the vendor ranking are found to be changing with confidence limit for sustainable vendor evaluation.

Practical implications

The fuzziness and randomness in relative ratings collects from a group of DMs are taken in the proposed methodology. The distinct approaches are compared with changing significance-level under stochastic, fuzzy and deterministic TOPSIS to acquire robustness in the ranking. The proposed SFTOPSIS model can be useful to practitioners from the petroleum sector.

Originality/value

The originality of the paper contributes to an application of the SFTOPSIS method that is the extension of FTOPSIS in the petro refining sector of a developing country. The sensitivity analysis with distinct significance-level shows the uncertainties in the collected ratings from the DMs that supports robustness in the ranking. It might be helpful for SC professionals from the petro refining sector, who assess the rank of the vendors at different confidence limits for sustainable supply of spare-parts. Further research in the petroleum industry from emerging economies needs to be undertaken to broaden its scope and applicability.
Revisiting foreign market entry motivations: the case of Korean commercial banks
Authors: Jung Young Hoon , Zhu Zhu , Nguyen Huy Will
Published: July 2021

Purpose

This study examines what motivates firms to go and remain abroad despite uncertain profit potential. In a departure from probing traditional market-seeking, profit-driven motives, the authors explore how domestically driven, sociocultural motivations may shape the foreign market entry decisions of Korean commercial banks (KCBs). The authors argue that, due to the power imbalance between KCBs and their chaebol clients within the historical and cultural contexts of their relationships, KCBs' foreign market entries may depend more on their clients' presence in these markets than on their profit potential.

Design/methodology/approach

The authors focus on the foreign market entries of KCBs and their client firms. Using the data of 8 KCBs and their client firms belonging to the 60 business groups (chaebols) of Korea, the authors analyze 6,577 observations involving the dyadic relationship between a KCB and its client firm in 15 host countries from 2005 to 2014.

Findings

The authors find that the number of clients' subsidiaries operating in foreign markets may increase the likelihood of KCBs entering these markets. Moreover, when KCBs earn more domestic profit from client firms, the potential Korean market in the host country is greater, and the institutional distance between the host country and Korea is smaller.

Practical implications

In addition to the critical role of a bank-centered financing system in advancing a developing country and its firms, the authors’ findings suggest that firms should pay attention to the local diaspora and the institutional distance between the host and home countries in order to manage power-imbalanced relationships and make them sustainable.

Originality/value

The study contributes to the literature on foreign market entry by demonstrating how the home country's sociocultural factors may worsen the power imbalance, thereby pushing firms to make seemingly irrational decisions to go and stay abroad. That is, KCBs' foreign operations may be a way of seeking relational benefits with client firms, which would serve as a source of long-term domestic market profits. The authors’ findings thus highlight the need to consider how sociocultural factors may also shape firms' decision-making in their international business.
Ethnography of economic globalization in Mapuche and forest territory of South-Central Chile
Authors: Carrasco Henríquez Noelia
Published: July 2021

Purpose

The purpose of this paper is to propose an ethnographic discussion surrounding the sociocultural dimensions of the contemporary economy, using the dynamics of monoculture expansion into the indigenous territories of South-Central Chile as an empirical reference.

Design/methodology/approach

From an ethnographic approach, the paper systematizes some ideas about the difference and inequality that have redrafted the current relationships between forestry companies and Mapuche communities within the context of international certification of forestry management.

Findings

Findings indicate that difference and inequality, are today managed from global economic rationality and their control impacts directly on quotidian life of diverse and unequal territories. Considering this, this paper gets to conclude that these conditions, while never ceasing to deepen their expression, have been recrafted from the new references of the global economy.

Research limitations/implications

For the critical ethnographic approach to be applied, it is necessary to design and implement wide access, which means this type of study usually has limitations when not being able to get to every scale of economic development. For this reason, it is important to keep the methodological discussion, about the ethnography of the economy.

Originality/value

The study puts in perspective intercultural relations and the inequality of territories in the framework of the global economy. Illustrates how the managing of the international market of wood and pulp design and insides in local quotidian life systems.
Effects of learning style and learning source preferences on organizational learning capability
Authors: Demetriou Gregoris , Papageorgiou George , Efstathiades Andreas
Published: July 2021

Purpose

The purpose of this research is the modeling of the relationship of Learning Style and Learning Source Preferences to Organizational Learning Capability (OLC).

Design/methodology/approach

A survey questionnaire gave us data from 274 employees in the hotel industry in Cyprus, which was chosen because it is a labor-intensive industry with big economic impact on the National Domestic Product (as per Cyprus Investment Promotion Agency this is more than 20%). SPSS and AMOS were used to analyse the proposed model.

Findings

The findings provided evidence to support the position that the proposed model demonstrates that OLC is affected by the Individual Learning Preferences (ILP) which are the learning style preference and the learning source preference of individual workers.

Research limitations/implications

The study did not consider the effect of learning style and learning source preferences on the different departments of a hotel. Further, a longitudinal study with more organizations within the hotel sector, or other economic sectors, was outside the scope of this study.

Practical implications

The proposed model can be used by organizations to reflect on how learning source and learning style preferences can affect the OLC.

Originality/value

What relevant research did not explore enough, is the learning preferences of individuals in their work environment and not as often seen, the learning styles or learning (dis)abilities of students in a school environment. Therefore, this research fulfills the need to study learning preferences in the business context and examines their effects on OLC.
A hybrid method for matching analysis of construction project characteristics with operation and maintenance requirements
Authors: Ma Guofeng , Wu Zhijiang , Wu Ming , Shang Shanshan
Published: July 2021

Purpose

The purpose of this study is to extract the real requirements of the owner (or users) for the construction project in the operation and maintenance stage completely and accurately and carry out the construction based on the requirements, to make the project status and operation and maintenance requirements (RO&M) consistent after delivered.

Design/methodology/approach

This study creatively proposes the operation and maintenance functions deployment (OMFD) under RO&M. In addition, the OPAR (naming is made up of the initials of owners, project, analysis and result) model is constructed to fully identify the requirements of both owners and projects. In this study, three typical construction projects are taken as examples to calculate the correlation strength between project characteristics (PC) and operation and maintenance requirements through the Apriori algorithm, and order parameters are obtained from the cost chain.

Findings

This study found that there are significant differences in the correlation strength between 11 types of RO&M and PC, in which the “cost of types” (TC) correlation of residential housing and factory buildings is the largest, while the largest correlation demand of commercial buildings is “safety of types” (TS) and “system” (S). Simultaneously, through the calculation of order parameters, the most influential factors on project characteristics are obtained.

Practical implications

This study could effectively help the owner (or users) to check whether the delivered project fully satisfy their real requirements and also extract the key technical points to realize RO&M, which can guide the accurate construction of the same type of projects.

Originality/value

This research establishes OPAR model to accurately identify the requirements of the project in the operation and maintenance stage and establishes the association rules between the requirements and the construction scheme, which is helpful for the project to construct under the expected requirements.
A critical analysis of water PPP failures in sub-Saharan Africa
Authors: Tariq Salman , Zhang Xueqing
Published: July 2021

Purpose

Top-down pressure from donors, public sector inefficiencies and fund deficits have steered the introduction of public–private partnerships (PPPs) in sub-Saharan Africa. However, PPP activities in the water sector have been quite insignificant compared to other infrastructure sectors in this region. In addition, a number of water PPPs have encountered great difficulties and subsequent failures. This study aims at unveiling the underlying reasons behind failures.

Design/methodology/approach

This study has classified the failure types of water PPPs and reviewed the development of water PPPs in sub-Saharan Africa to identify failed ones. Eight failed case studies are completed through the rigorous approach of event sequence mapping.

Findings

Nine root causes of water PPP failure are identified through a thorough examination of these failed water PPP cases and the interrelationships between these failure causes are established. The failure causes are further generalized through literature focusing on water PPP failures in developing countries and problematic issues that hinder the implementation of successful water PPPs across different Sub-Saharan African countries. Recommendations are provided for future improvements in carrying out water PPPs in Sub-Saharan Africa by learning past lessons and drawing experiences.

Originality/value

This is the first case study on water PPP failures in Sub-Saharan Africa from a construction management perspective. This study will help governments and the private sector in developing stronger future water PPPs.
Entropy generation in MHD free convection of nanoliquid within a square open chamber with a solid body
Authors: Chinnasamy Sivaraj , E. Vignesh , Sheremet Mikhail
Published: July 2021

Purpose

The study aims to investigate magnetohydrodynamics thermal convection energy transference and entropy production in an open chamber saturated with ferrofluid having an isothermal solid block.

Design/methodology/approach

Analysis of thermal convection phenomenon was performed for an open chamber saturated with a nanofluid having an isothermal solid unit placed inside the cavity with various aspect ratios. The left border temperature is kept at Tc. An external cooled nanofluid of fixed temperature Tc penetrates into the domain from the right open border. The nanofluid circulation is Newtonian, incompressible, and laminar. The uniform magnetic field of strength B at the tilted angle of γ is applied. The finite volume technique is used to work out the non-linear equations of liquid motion and energy transport. For Rayleigh number (Ra=1e+7), numerical simulations were executed for varying the solid volume fractions of the nanofluid (ϕ = 0.01–0.04), the aspect ratios of a solid body (As = 0.25–4), the Hartmann number (Ha = 0–100), the magnetic influence inclination angle (γ = 0–π/2) and the non-dimensional temperature drop (Ω = 0.001–0.1) on the liquid motion, heat transference and entropy production.

Findings

Numerical outcomes are demonstrated by using isolines of temperature and stream function, profiles of mean Nusselt number and entropy generations. The results indicate that the entropy generation rate and mean Nu can be decreased with an increase in Ha. The inner solid block of As = 0.25 reflects the maximum heat transfer rate in comparison with other considered blocks. The addition of nano-sized particles results in a growth of energy transport and mean entropy generations.

Originality/value

An efficient computational technique has been developed to solve natural convection problem for an open chamber. The originality of this research is to scrutinize the convective transport and entropy production in an open domain with inner body. The outcomes would benefit scientists and engineers to become familiar with the investigation of convective energy transference and entropy generation in open chambers with inner bodies, and the way to predict the energy transference strength in the advanced engineering systems.
Numerical study of cavitating flow over hydrofoil in the presence of air
Authors: Wróblewski Włodzimierz , Bochon Krzysztof , Majkut Mirosław , Rusin Krzysztof , Hasani Malekshah Emad
Published: July 2021

Purpose

The presence of air in the water flow over the hydrofoil is investigated. The examined hydrofoil is ClarkY 11.7% with an angle of attack of 8 deg. The flow simulations are performed with the assumption of different models. The Singhal cavitation model and the models which resolve the non-condensable gas including 2phases and 3phases are implemented in the numerical model. The calculations are performed with the uRANS model with assumption of the constant temperature of the mixture. The two-phase flow is simulated with a mixture model. The dynamics and structures of cavities are compared with literature data and experimental results.

Design/methodology/approach

The cavitation regime can be observed in some working conditions of turbomachines. The phase transition, which appears on the blades, is the source of high dynamic forces, noise and also can lead to the intensive erosion of the blade surfaces. The need to control this process and to prevent or reduce the undesirable effects can be fulfilled by the application of non-condensable gases to the liquid.

Findings

The results show that the Singhal cavitation model predicts the cavity structure and related characteristics differently with 2phases and 3phases models at low cavitation number where the cavitating flow is highly dynamic. On the other hand, the impact of dissolved air on the cloud structure and dynamic characteristic of cavitating flow is gently observable.

Originality/value

The originality of this paper is the evaluation of different numerical cavitation models for the prediction of dynamic characteristics of cavitating flow in the presence of air.
Optimisation of restaurants’ hospitality performance: the roles of innovation, internal and external power understanding capability
Authors: Rahman Muhammad Sabbir , Hassan Hasliza , Fattah Fadi Abdel Muniem Abdel
Published: July 2021

Purpose

This study aims to explore which drivers of innovation in the hospitality industry optimise hospitality performance in a multivariate nexus of restaurants’ value system for hospitality (VSH) and internal–external power understanding capability.

Design/methodology/approach

The study applied a cross-sectional questionnaire survey research design, targeting employees who were working in full-service restaurants. Descriptive statistic, confirmatory factor analysis and structural equation modelling (SEM) were performed. A total of 364 respondent’s responses were used in the data analyses.

Findings

Results of the empirical analysis reveal that collaborative innovation capability has the closest relationship with hospitality performance optimisation (HPO), followed by VSH, employee creativity and knowledge management system capability. The analysis with the bootstrapping method shows that VSH mediates the relationship between the drivers of innovation and HPO. The empirical results also suggest that firms’ capabilities of understanding internal and external environments are significant moderators of the relationship between VSH and HPO.

Research limitations/implications

The empirical findings provide restaurant managers with an improved understanding of how the drivers of innovation capability influence HPO. Findings from this research emphasise that hotel managers should consider internal and external environmental issues to adjust their strategies for improving hospitality performance in a competitive environment.

Practical implications

Findings suggest that restaurant managers should implement the drivers of innovation in their respective work environment, together with their adequate involvement with staff and understanding of environmental issues, to produce innovative hospitality strategies.

Originality/value

This research contributes a comprehensive framework of HPO in the restaurant business setting that leads to a competitive advantage. To the best of the authors’ knowledge, this research is one of the pioneer studies to contribute to the hospitality literature that investigates the effect of the drivers of innovation on VSH and HPO by considering the moderation role of internal and external environmental understanding capability.