bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel human cell expression method reveals the role and prevalence of posttranslational modification in non-muscle tropomyosins
Authors: Carman Peter J. , Barrie Kyle R. , Dominguez Roberto
Published: April 2021

Biochemical studies require large protein quantities, which are typically obtained using bacterial expression. However, the folding machinery of bacteria is inadequate for many mammalian proteins, which additionally undergo posttranslational modifications (PTMs) that bacteria, yeast, or insect cells cannot perform. Many proteins also require native N- and C-termini and cannot tolerate extra tag amino acids for function. Tropomyosin, a coiled coil that decorates most actin filaments in cells, requires both native N- and C-termini and PTMs, specifically N-terminal acetylation, to polymerize along actin filaments. Here, we describe a new method that combines native protein expression in human cells with an intein-based purification tag that can be precisely removed after purification. Using this method, we expressed several non-muscle tropomyosin isoforms. Mammalian cell-expressed tropomyosins are functionally different from theirE. coli-expressed counterparts, display multiple types of PTMs, and can form heterodimers. This method can be extended to other proteins, as demonstrated here for α-synuclein.
The Okur-Chung Neurodevelopmental Syndrome (OCNDS) mutation CK2K198Rleads to a rewiring of kinase specificity
Authors: Caefer Danielle M , Phan Nhat Q , Liddle Jennifer C , Balsbaugh Jeremy L , O’Shea Joseph P , Tzingounis Anastasios V , Schwartz Daniel
Published: April 2021

Okur-Chung Neurodevelopmental Syndrome (OCNDS) is caused by heterozygous mutations to the CSNK2A1 gene, which encodes the alpha subunit of casein kinase II (CK2). The most frequently occurring mutation is lysine 198 to arginine (K198R). To investigate the impact of this mutation, we first generated a high-resolution phosphorylation motif of CK2WT, including the first characterization of specificity for tyrosine phosphorylation activity. A second high resolution motif representing CK2K198Rsubstrate specificity was also generated. Here we report for the first time the impact of the OCNDS associated CK2K198Rmutation. Contrary to prior speculation, the mutation does not result in a loss of function, but rather shifts the substrate specificity of the kinase. Broadly speaking the mutation leads to 1) a decreased preference for acidic residues in the +1 position, 2) a decreased preference for threonine phosphorylation, 3) an increased preference for tyrosine phosphorylation, and 4) an alteration of the tyrosine phosphorylation specificity motif. To further investigate the result of this mutation we have developed a probability-based scoring method, allowing us to predict shifts in phosphorylation in the K198R mutant relative to the wild type kinase. As an initial step we have applied the methodology to the set of axonally localized ion channels in an effort to uncover potential alterations of the phosphoproteome associated with the OCNDS disease condition.
Early life Western diet-induced memory impairments and gut microbiome changes in female rats are long-lasting despite healthy dietary intervention
Authors: Tsan Linda , Sun Shan , Bridi Lana , Chirala Lekha S. , Noble Emily E. , Fodor Anthony A. , Kanoski Scott E.
Published: April 2021

Objective

Consumption of a Western diet during adolescence results in hippocampus (HPC)-dependent memory impairments and gut microbiome dysbiosis. Whether these adverse outcomes are reversible in adulthood following intervention with a healthy diet is unknown. Here we assessed the short- and long-term effects of adolescent consumption of a Western diet enriched with either sugar alone, or sugar and fat on metabolic outcomes, HPC-dependent memory, and gut microbiota.

Methods

Adolescent female rats (PN 26) were fed a standard chow diet (CTL), a chow diet with access to 11% sugar solution (SUG), or a junk food cafeteria-style diet (CAF) containing a variety of fat- and/or sugar-enriched foods. During adulthood (PN 65+), metabolic outcomes, HPC-dependent memory, and gut microbial populations were evaluated both before and after a 5-week dietary intervention period where all groups were fed a diet of water standard chow.

Results

Prior to the dietary intervention both the CAF and SUG groups demonstrated impaired HPC-dependent memory, increased adiposity, and altered gut microbial populations relative to controls. However, impaired peripheral glucose regulation was only observed in the SUG group. The dietary intervention reversed the metabolic dysfunction in both the CAF and SUG groups, whereas HPC-dependent memory impairments were reversed in the SUG, but not the CAF group. The composition of the gut microbiota remained distinct from controls in both groups after dietary intervention.

Conclusions

While the metabolic impairments associated with adolescent cafeteria diet consumption are reversible in adulthood with dietary intervention, the HPC-dependent memory impairments and the gut microbiome dysbiosis persist.
Exploiting Family History in Aggregation Unit-based Genetic Association Tests
Authors: Wang Yanbing , Chen Han , Peloso Gina Marie , DeStefano Anita , Dupuis Josée
Published: April 2021

The development of sequencing technology calls for new powerful methods to detect disease associations and lower the cost of sequencing studies. Family history (FH) contains information on disease status of relatives, adding valuable information about the probands’ health problems and risk of diseases. Incorporating data from FH is a cost-effective way to improve statistical evidence in genetic studies, and moreover, overcomes limitations in study designs with insufficient cases or missing genotype information for association analysis. We proposed family history aggregation unit-based test (FHAT) and optimal FHAT (FHAT-O) to exploit available FH for rare variant association analysis. Moreover, we extended liability threshold model of case-control status and FH (LT-FH) method in aggregated unit-based methods and compared that with FHAT and FHAT-O. The computational efficiency and flexibility of the FHAT and FHAT-O were demonstrated through both simulations and applications. We showed that FHAT, FHAT-O and LT-FH method offer reasonable control of the type I error unless case/control ratio is extremely unbalanced, in which case they result in smaller inflation than that observed with conventional methods excluding FH. We also demonstrated that FHAT and FHAT-O are more powerful than LT-FH method and conventional methods in many scenarios. By applying FHAT and FHAT-O to the analysis of all cause dementia and hypertension using the exome sequencing data from the UK Biobank, we showed that our methods can improve significance for known regions. Furthermore, we replicated the previous associations in all cause dementia and hypertension and detected novel regions through the exome-wide analysis.
Interspecies recombination has driven the macroevolution of cassava mosaic begomoviruses
Authors: Crespo-Bellido Alvin , Steen Hoyer J. , Dubey Divya , Jeannot Ronica B. , Duffy Siobain
Published: April 2021

Begomoviruses (familyGeminiviridae, genusBegomovirus) significantly hamper crop production and threaten food security around the world. The frequent emergence of new begomovirus genotypes is facilitated by high mutation frequencies and the propensity to recombine and reassort. Homologous recombination has been especially implicated in the emergence of novel cassava mosaic begomovirus (CMB) genotypes, which cause cassava mosaic disease (CMD). Cassava (Manihot esculenta) is a staple food crop throughout Africa, and an important industrial crop in Asia, two continents where production is severely constrained by CMD. The CMD species complex is comprised of 11 bipartite begomovirus species with ample distribution throughout Africa and the Indian subcontinent. While recombination is regarded as a frequent occurrence for CMBs, a revised, systematic assessment of recombination and its impact on CMB phylogeny is currently lacking. We assembled datasets of all publicly available, full-length DNA-A (n=880) and DNA-B (n=369) nucleotide sequences from the 11 recognized CMB species. Phylogenetic networks and complementary recombination detection methods revealed extensive recombination among the CMB sequences. Six out of the eleven species have descended from unique interspecies recombination events. Estimates of recombination and mutation rates revealed that all species experience mutation more frequently than recombination, but measures of population divergence indicate that recombination is largely responsible for the genetic differences between species. Our results support that recombination has significantly impacted the CMB phylogeny and is driving speciation in the CMD species complex.

IMPORTANCE

Cassava mosaic disease (CMD) is a significant threat to cassava production throughout Africa and Asia. CMD is caused by a complex comprised of 11 recognized virus species exhibiting accelerated rates of evolution, driven by high frequencies of mutation and genetic exchange. Here, we present a systematic analysis of the contribution of genetic exchange to cassava mosaic virus diversity. Most of these species emerged as a result of genetic exchange. This is the first study to report the significant impact of genetic exchange on speciation in a group of viruses.
Unraveling the host-selective toxic interaction of cassiicolin with lipid membranes and its cytotoxicity
Authors: Ngo Kien Xuan , Quoc Nguyen Bao , Nguyen Phuong Doan N. , Furusho Hirotoshi , Miyata Makoto , Shimonaka Tomomi , Chau Nguyen Ngoc Bao , Vinh Nguyen Phuong , Nghia Nguyen Anh , Mohammed Tareg Omer , Ichikawa Takehiko , Kodera Noriyuki , Konno Hiroki , Fukuma Takeshi , Ando Toshio
Published: April 2021

Cassiicolin (Cas), a toxin produced byCorynespora cassiicola, is responsible for corynespora leaf fall disease in rubber trees. Currently, the molecular mechanism of the cytotoxicity of Cas and its host selectivity have not been fully elucidated. Here, we analyzed the binding of Cas1 and Cas2 to membranes consisting of different plant lipids and their membrane-disruption activities. Using high-speed atomic force microscopy and confocal microscopy, we reveal that the binding and disruption activities of Cas1 and Cas2 on lipid membranes are strongly dependent on the specific plant lipids. The negative phospholipids, glycerolipids, and sterols are more susceptible to membrane damage caused by Cas1 and Cas2 than neutral phospholipids and betaine lipids. Cytotoxicity tests on rubber leaves of RRIV 1, RRIV 4, and PB 255 clones suggest that the toxins cause necrosis of rubber leaves, except for the strong resistance of PB 255 against Cas2. Cryo- SEM analyses of necrotic leaf tissues exposed to Cas1 confirm that cytoplasmic membranes are vulnerable to the toxin. Thus, the host selectivity of Cas toxin is attained by the lipid-dependent binding activity of Cas to the membrane, and the cytotoxicity of Cas arises from its ability to form biofilm-like structures and disrupt specific membranes.

Graphic Abstract

Highlights

Cas1 and Cas2 directly damage and cause necrosis in the leaves of specific rubber clones.

Cas1 and Cas2 can form biofilm-like structures on specific lipid membranes (negative phospholipids, glycerolipids, and sterols). The biofilm-like formation of Cas toxin plays an important role in selective disruption on lipid membranes.

Vulnerability of the specific cytoplasmic membranes to the selective Cas toxin that is the most remarkable feature of cytotoxicity of Cas toxin on plant cells.
The males of the parasitoid wasp,Nasonia vitripennis, can identify which fly hosts contain females
Authors: Prazapati Garima , Yadav Ankit , Ambili Anoop , Sharma Abhilasha , Raychoudhury Rhitoban
Published: April 2021

The reproductive success of a male is limited by the number of females it can mate with. Thus, males deploy elaborate mate-finding strategies to maximize access to females. In the haplodiploid wasp genus, Nasonia, which are parasitoids of cyclorrhaphous flies, mate-finding is restricted to the natal patch, where males compete for access to females. This study investigates whether there are any additional mate finding strategies of males, especially, whether they can identify the presence of adult females which are still inside the fly host. Results reveal that only one out of the four species, N. vitripennis, can distinguish which hosts specifically have adult female wasps indicating a species-specific unique mate-finding capability. Behavioral assays revealed that the cues used by N. vitripennis males are olfactory in nature and not auditory or visual. GC-MS analyses show that these olfactory cues are female-specific cuticular hydrocarbons (CHCs), possibly emanating from within the fly puparium. Further assays indicated that N. vitripennis males can also detect differences in the concentrations of compounds to identify female-specific cues from male-specific ones. This study, therefore, uncovers a previously unknown mate-finding strategy in one of the most widely studied parasitoid wasp.
A CRISPR/Cas12a-assisted platform for identification and quantification of single CpG methylation sites
Authors: van Dongen J.E. , Berendsen J.T.W. , Eijkel J.C.T. , Segerink L.I.
Published: April 2021

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/associated nuclease (Cas) systems have repeatedly shown to have excellent performance in nucleotide sensing applications1–5. High specificity and selectivity of Cas effector proteins is determined by the CRISPR RNA’s (crRNA’s) interchangeable spacer sequence, as well as position and number of mismatches between target sequence and the crRNA sequence1. Some diseases are characterized by epigenetic alterations rather than nucleotide changes, and are therefore unsuitable for CRISPR-assisted sensing methods. Here we demonstrate a method to discriminate single CpG site methylation in DNA, which is an epigenetic alteration, by the use of methylation-sensitive restriction enzymes (MSREs) followed by Cas12a-assisted sensing. Non-methylated sequences are digested by MSREs, resulting in fragmentation of the target sequence that influences the R-loop formation between crRNA and target DNA. We show that fragment size, fragmentation position and number of fragments influence the subsequent collateraltrans-cleavage activity towards single stranded DNA (ssDNA), enabling deducting the methylation position from the cleavage activity. Utilizing MSREs in combination with Cas12a, single CpG site methylation levels of a cancer gene were for the first time determined. The modularity of both Cas12a and MSREs provide a high level of versatility to the Cas12a–MSRE combined sensing method, which opens the possibility to easily and rapidly study single CpG methylation sites for disease detection.
Rapid Kinetic Fingerprinting of Single Nucleic Acid Molecules by a FRET-based Dynamic Nanosensor
Authors: Khanna Kunal , Mandal Shankar , Blanchard Aaron T. , Tewari Muneesh , Johnson-Buck Alexander , Walter Nils G.
Published: April 2021

Biofluids contain cell-free nucleic acids such as microRNAs (miRNAs) and circulating tumor-derived DNAs (ctDNAs) that have emerged as promising disease biomarkers. Conventional detection of these biomarkers by digital PCR and next generation sequencing, although highly sensitive, requires time-consuming extraction and amplification steps that increase the risk of sample loss and cross-contamination, respectively. To achieve the direct, rapid detection of miRNAs and ctDNAs with near-perfect specificity and single-molecule level sensitivity, we herein describe an accelerated amplification-free single-molecule kinetic fingerprinting. This approach, termed intramolecular single-molecule recognition through equilibrium Poisson sampling (iSiMREPS), exploits a dynamic DNA nanosensor comprising a surface anchor and a pair of fluorescent detection probes: one probe captures individual target molecules onto the surface, while the other transiently interrogates them to generate kinetic fingerprints by intramolecular single-molecule Förster resonance energy transfer (smFRET). Formamide is used to further accelerate the kinetics of probe-target interactions and fingerprinting, while background signals are reduced by removing non-target-bound probes from the surface using toehold-mediated strand displacement. We show that iSiMREPS can detect in as little as 10 seconds two distinct, promising cancer biomarkers—miR-141 and a commonEGFRexon 19 deletion—reaching a limit of detection (LOD) of ~3 fM and a mutant allele fraction among excess wild-type as low as 1 in 1 million, or 0.0001%. We anticipate that iSiMREPS will find utility in research and clinical diagnostics based on its features of rapid detection, high specificity, sensitivity, and generalizability.
Constrained G4 structures unveil topology specificity of known and new G4 binding proteins
Authors: Pipier A. , Devaux A. , Lavergne T. , Adrait A. , Couté Y. , Britton S. , Calsou P. , Riou J.F. , Defrancq E. , Gomez D.
Published: April 2021

G-quadruplexes (G4) are non-canonical secondary structures consisting in stacked tetrads of hydrogen-bonded guanines bases. An essential feature of G4 is their intrinsic polymorphic nature, which is characterized by the equilibrium between several conformations (also called topologies) and the presence of different types of loops with variable lengths. In cells, G4 functions rely on protein or enzymatic factors that recognize and promote or resolve these structures. In order to characterize new G4-dependent mechanisms, extensive researches aimed at identifying new G4 binding proteins. Using G-rich single-stranded oligonucleotides that adopt non-controlled G4 conformations, a large number of G4-binding proteins have been identifiedin vitro, but their specificity towards G4 topology remained unknown.

Constrained G4 structures are biomolecular objects based on the use of a rigid cyclic peptide scaffold as a template for directing the intramolecular assembly of the anchored oligonucleotides into a single and stabilized G4 topology. Here, using various constrained RNA or DNA G4 as baits in human cell extracts, we establish the topology preference of several well-known G4-interacting factors. Moreover, we identify new G4-interacting proteins such as the NELF complex involved in the RNA-Pol II pausing mechanism, and we show that it impacts the clastogenic effect of the G4-ligand pyridostatin.
Using AI predicted personality to enhance advertising effectiveness
Authors: Shumanov Michael , Cooper Holly , Ewing Mike
Published: April 2021

Purpose

The purpose of this study is twofold: first to demonstrate the application of an algorithm using contextual data to ascertain consumer personality traits; and second to explore the factors impacting the relationship between personality traits and advertisement persuasiveness.

Design/methodology/approach

A mixed-method approach that comprises two distinct yet complementary studies. The first uses quantitative methods and is based on a sample of 35,264 retail banking customers. Study 2 explores the findings that emerge from Study 1 using qualitative methods.

Findings

This paper finds that matching consumer personality with congruent advertising messages can lead to more effective consumer persuasion for most personality types. For consumers who exhibit neurotic personality traits, ameliorating perceived risks during purchasing and providing cues for social acceptance and goal attainment are important factors for advertising effectiveness. These factors also had a positive impact on the purchasing behaviour of extroverted consumers.

Research limitations/implications

This research focusses on understanding purchasing behaviour based on the most dominant personality trait. However, people are likely to exhibit a combination of most or even all of the Big Five personality traits.

Practical implications

Building on advances in natural language processing, enabling the identification of personality from language, this study demonstrates the possibility of influencing consumer behaviour by matching machine inferred personality to congruent persuasive advertising. It is one of the few studies to use contextual instead of social media data to capture individual personality. Such data serves to capture an authentic rather than contrived persona. Further, the study identifies the factors that may moderate this relationship and thereby provides an explanation of why some personality traits exhibit differences in purchasing behaviour from those that are anticipated by existing theory.

Originality/value

Although the idea that people are more likely to be responsive to advertising messages that are congruent with their personality type has already been successfully applied by advertising practitioners and documented by advertising scholars, this study extends existing research by identifying the factors that may moderate this relationship and thereby provides an explanation why some personality traits may exhibit differences in purchasing behaviour from those that are anticipated by existing theory.
Forming digital identities in social networks: the role of privacy concerns and self-esteem
Authors: Papaioannou Thanos , Tsohou Aggeliki , Karyda Maria
Published: April 2021

Purpose

This paper aims to identify the data elements that social network sites (SNS) users consider important for shaping their digital identity and explore how users’ privacy concerns, self-esteem and the chosen SNS shape this process.

Design/methodology/approach

This study conducted an online survey with the participation of 759 individuals, to examine the influence of privacy concerns, self-esteem and the chosen SNS platform, on the shaping of the digital identity, through a classification of identity elements that users disclose when using a SNS, the Rosenberg self-esteem scale and relevant constructs from the literature.

Findings

Findings reveal that users consider the name, gender, picture, interests and job as most important elements for shaping their digital identity. They also demonstrate that privacy concerns do not seem to affect the amount of information users choose to publish when shaping their digital identity. Specific characteristics of SNS platforms are found to affect the way that users shape their digital identity and their privacy behavior. Finally, self-esteem was found to affect privacy concerns and digital identity formation.

Research limitations/implications

To avoid a lengthy questionnaire and the risk of low participation, the respondents answered the questions for one SNS of their choice instead of answering the full questionnaire for each SNS that they use. The survey included the most popular SNSs at the time of the survey in terms of popularity.

Practical implications

The results contribute to the theory by furthering our knowledge on the elements that shape digital identity and by providing evidence with regard to the role of privacy and self-esteem within social networking. In practice, they can be useful for SNS providers, as well as for entities that design security and privacy awareness campaigns.

Originality/value

This paper identifies novel factors that influence digital identity formation, including the specific SNS used with its particular characteristics in combination with privacy concerns and self-esteem of the user.
Collective information security behaviour: a technology-driven framework
Authors: Snyman Dirk P. , Kruger Hennie
Published: April 2021

Purpose

This paper aims to present the development of a framework for evaluating group behaviour in information security in practice.

Design/methodology/approach

Information security behavioural threshold analysis is used as the theoretical foundation for the proposed framework. The suitability of the proposed framework is evaluated based on two sets of qualitative measures (general frameworks and information security frameworks) which were identified from literature. The successful evaluation of the proposed framework, guided by the identified evaluation measures, is presented in terms of positive practical applications, as well as positive peer review and publication of the underlying theory.

Findings

A methodology to formalise a framework to analyse group behaviour in information security can successfully be applied in a practical environment. This application takes the framework from only a theoretical conceptualisation to an implementable solution to evaluate and positively influence information security group behaviour.

Practical implications

Behavioural threshold analysis is identified as a practical mechanism to evaluate information security group behaviour. The suggested framework, as implemented in a management decision support system (DSS), allows practitioners to assess the security behaviour and awareness in their organisation. The resulting information can be used to exert an influence for positive change in the information security of the organisation.

Originality/value

A novel conceptual mapping of two sets of qualitative evaluation measures is presented and used to evaluate the proposed framework. The resulting framework is made practical through its encapsulation in a DSS.
Evaluating the profit efficiency of bioenergy industry and its determinants in EU28 region
Authors: Zubair A.O. , Alsaleh Mohd , Abdul-Rahim Abdul Samad
Published: April 2021

Purpose

The purpose of this study is to evaluate the profit efficiency of bioenergy industry and its determinants in EU28 region roadmaps for the transition towards energy efficiency which is increasingly perceived by stakeholders, researchers and the public as a pathway to bring dependency on fossil resources to a significant reduction. Many studies overlooked the importance of profit efficiency as a factor for bioenergy industry business improvement. More so, external environmental variables can play a key role in achieving profit efficiency in the industry.

Design/methodology/approach

This paper seeks to answer the questions on the following: (1) the profit efficiency level using the data envelopment analysis (DEA) approach in the EU28 region during the period between 1990 and 2018; and (2) to explore the impacts of external environmental variables on the profit efficiency level using panel regression model in the EU28 region during the period between 1990 and 2018.

Findings

Results revealed that gross domestic product, size of biomass and investment are essential for the development of the bioenergy industry and positively influence on profit efficiency level. The increase in temperature change decreased the profit efficiency level during 1990–2018.

Research limitations/implications

For those profit-inefficient bioenergy industries in countries such as Cyprus and Ireland, participation in innovative programs, expanding a knowledge-based economic system and implementation of support policy for bioenergy technologies, by investing in biomass sources that are suitable for their respective renewable energy development will enhance specialization, resource efficiency and improved profitability can be expected in future.

Originality/value

Unlike other previous studies, this study investigated the profit efficiency by applying the DEA statistical method. Moreover, the authors have applied a second regression analysis to estimate the impacts of macroeconomic and microeconomic variables on the profit efficiency level. This study has focused on the EU28 region, including both developed and developing countries, to compare the level of profit efficiency levels in the selected sample. The authors have applied data panel analysis for the period from 1990 to 2018. No previous study has applied the methods, samples and periods as those used in this study. Therefore, this study contributes significantly to the bioenergy industry specifically and the renewable energy industry in general and to the associated extant research.
Digital transformation in West Africa: a two country, two-sector analysis
Authors: Madichie Nnamdi O. , Bolat Elvira , Taura Nasiru
Published: April 2021

Purpose

The purpose of this paper is to explore opportunities and challenges of accelerating digital entrepreneurship development in key economic growth sectors in West Africa.

Design/methodology/approach

The study uses case illustrations from the media and agriculture sectors to highlight some of the opportunities and challenges that have shaped current business practices in this digital space in West Africa.

Findings

Technological infrastructure featured as one of the main challenges for fostering success in the media-tech cases and perhaps linked to the low internet penetration rates. Likewise, infrastructure proved to be a challenge in the agri-tech sector cases.

Originality/value

This study highlights the importance of partnerships within the entrepreneurship ecosystems as a critical condition for ensuring positive benefits for all stakeholders within the entrepreneurial ecosystem taken from the lens of West Africa.
The resilience and realignment of house prices in the era of Covid-19*
Authors: Duca John V. , Hoesli Martin , Montezuma Joaquim
Published: April 2021

Purpose

The study aims to analyze the effects of the Covid-19 pandemic on house prices.

Design/methodology/approach

The authors start by discussing the possibility that house price indexes may not fully incorporate the effects of the pandemic as of yet. Against the background of the pandemic, the authors then analyze economic and behavioral effects affecting house prices. The authors also discuss how the linkages between tourism and house prices have been affected. The authors further present evidence of an emerging shift in preferences from urban locations to more peripheral ones.

Findings

The authors report variance in the evolution of house prices across countries at the onset of the pandemic, with locations depending heavily on tourism showing slower price appreciation while appreciation has firmed in other places. The authors argue that the resilience of house prices is not only because of the low-interest rate environment and government efforts to support firms and households, but also behavioral factors. In some locations, the price of condominiums has declined relative to the price of detached houses. This could indicate that wealthier households are seeking more space and larger units as a result of the crisis. There is also evidence of a downward pressure on rents, leading to increased price–rent ratios in the USA.

Originality/value

By considering both economic and behavioral factors, this paper provides for a better understanding of the resilience and realignment of house prices at the onset of the Covid-19 pandemic.
The growing Russian role in sub-Saharan Africa: interests, opportunities and limitations
Authors: Elbassoussy Ahmed
Published: April 2021

Purpose

The purpose of this study is to identify various Russian manifestations on expanding its role in sub-Saharan Africa, as well as shed light on the major obstacles it may face.

Design/methodology/approach

The research paper uses the “national role theory” to analyze the factors that helped in the growing Russian role in sub-Saharan African countries. It assumes that every state seeks to play a particular role, and that role is reflected in its foreign policy, which is known as “role performance,” and this role originates from several sources. On the other hand, this role faces various obstacles, mostly from the external environment, especially the international system’s structure, global values and international obligations, known as “role prescriptions.”

Findings

Despite Russia’s ability to use all its capacities in expanding its role in the African continent, the degree of its influence varied from one field to another. While it was very influential in the military, security, political, diplomatic and technical fields, it is relatively less in the economic and counter-terrorism areas.

Research limitations/implications

This study paves the way for further researches related to international competition over sub-Saharan Africa, whether economically, militarily or politically, in addition to other studies related to potential cooperation opportunities, especially in security and combating terrorism.

Originality/value

This research’s significance stems from using the existing theoretical structure represented in national role theory in analyzing the Russian orientation toward sub-Saharan Africa, giving more attention to the latest developments in Russian strategy, as well as clarifying the major obstacles that may hinder its activities.
Corporate sustainability assessment based on rough-grey set theory
Authors: Karimi Tooraj , Hojati Arvin
Published: April 2021

Purpose

The purpose of this paper is to design an inference engine to measure the level of readiness of each bank before starting the corporate sustainability auditing process. Based on the output of the designed inference engine, the audition team can decide about the audition resources and the auditing process.

Design/methodology/approach

In this paper, the hybrid rough and grey set theory are used to design and create a rule model system to measure the sustainability level of banks. First, 16 rule models are extracted using rough set theory (RST), and the cross-validation of each model is done. Then, the grey clustering is used to combine the same condition attributes and improve the validity of the final model. A total of 16 new rule models are extracted based on the decreased condition attributes, and the best model is selected based on the cross-validation results.

Findings

By comparing the accuracy of rough-gray’s rule models and as a result of decreasing the condition attributes, a proper increase in the accuracy of all models is obtained. Finally, the Naive/Genetic/object-related reducts model with 95.6% accuracy is selected as an inference engine to measure new banks’ readiness level.

Originality/value

Sustainability measurement of banks based on RST is a new approach in the field of corporate sustainability. Furthermore, using the grey clustering for combining the condition attributes is a novel solution for improving the accuracy of the rule models.
Sustainable optimal ordering quantity for non-instantaneous deteriorating items under joint replenishment with substitution and carbon emission
Authors: Singh Ranu , Mishra Vinod Kumar
Published: April 2021

Purpose

Carbon emission is a significant issue for the current business market and global warming. Nowadays, most countries have focused to reduce the environmental impact of business with durable financial benefits. The purpose of this study is to optimize the entire cost functions with carbon emission and to find the sustainable optimal ordering quantity for retailers.

Design/methodology/approach

This paper illustrates a sustainable inventory model having a set of two non-instantaneous substitutable deteriorating items under joint replenishment with carbon emission. In this model demand and deterioration rate are considered as deterministic, constant and triangular fuzzy numbers. The objective is to find the optimal ordering quantity for retailers and to minimize the total cost function per unit time with carbon emission. The model is then solved with the help of Maple software.

Findings

This paper presents a solution method and also develop an algorithm to determine the order quantities which optimize the total cost function. A numerical experiment illustrates the improvement in optimal total cost of the inventory model with substitution over without substitution. The graphical results show the convexity of the cost function. Finally, sensitivity analysis is given to get the impact of parameters and validity of the model.

Originality/value

This study considers a set of two non-instantaneous substitutable deteriorating items under joint replenishment with carbon emission. From the literature review, in the authors’ knowledge no researcher has undergone this kind of study.
Discerning citation patterns in dominant BME literature streams: lessons for BME scholars
Authors: Arbaugh J. Ben , Hwang Alvin , McNally Jeffrey J. , Fornaciari Charles J. , Burke-Smalley Lisa A.
Published: April 2021

Purpose

This paper aims to compare the nature of three different business and management education (BME) research streams (online/blended learning, entrepreneurship education and experiential learning), along with their citation sources to draw insights on their support and legitimacy bases, with lessons on improving such support and legitimacy for the streams and the wider BME research field.

Design/methodology/approach

The authors analyze the nature of three BME research streams and their citation sources through tests of differences across streams.

Findings

The three streams differ in research foci and approaches such as the use of managerial samples in experiential learning, quantitative studies in online/blended education and literature reviews in entrepreneurship education. They also differ in sources of legitimacy recognition and avenues for mobilization of support. The underlying literature development pattern of the experiential learning stream indicates a need for BME scholars to identify and build on each other’s work.

Research limitations/implications

Identification of different research bases and key supporting literature in the different streams shows important core articles that are useful to build research in each stream.

Practical implications

Readers will understand the different research bases supporting the three research streams, along with their targeted audience and practice implications.

Social implications

The discovery of different support bases for the three different streams helps identify the network of authors and relationships that have been built in each stream.

Originality/value

According to the authors’ knowledge, this paper is the first to uncover differences in nature and citation sources of the three continuously growing BME research streams with recommendations on ways to improve the support of the three streams.
Experimental investigation of various ethanol blends impact on combustion and emissions characteristics of diesel ignited dual fuel HCCI engine
Authors: Gawale Ganesh Rupchand , G. Naga Srinivasulu
Published: April 2021

Purpose

Homogeneous charge compression ignition (HCCI) engine is an advanced combustion method to use alternate fuel with higher fuel economy and, reduce NOX and soot emissions. This paper aims to investigate the influence of ethanol fraction (ethanol plus gasoline) on dual fuel HCCI engine performance.

Design/methodology/approach

In this study, the existing CI engine is modified into dual fuel HCCI engine by attaching the carburetor to the inlet manifold for the supply of ethanol blend (E40/E60/E80/E100). The mixture of ethanol blend and the air is ignited by diesel through a fuel injector into the combustion chamber at the end of the compression stroke. The experiments are conducted for high load conditions on the engine i.e. 2.8 kW and 3.5 kW maximum output power for 1,500 constant rpm.

Findings

It is noticed from the experimental results that, with an increase of ethanol in the blends, ignition delay (ID) increases and the start of combustion is retarded. It is noticed that E100 shows the highest ID and low in-cylinder pressure; however, E40 shows the lowest ID compared to higher fractions of ethanol blends. An increase in ethanol proportion reduces NOX and smoke opacity but, HC and CO emissions increase compared to pure diesel mode engine. E100 plus diesel dual-fuel HCCI engine shows the highest brake thermal efficiency compared to remaining ethanol blends and baseline diesel engine.

Originality/value

This experimental study concluded that E100 plus diesel and E80 plus diesel gave optimum dual fuel HCCI engine performance for 2.8 kW and 3.5 kW rated power, respectively.
Increased grazing intensities induce differentiation of the relationships between functional traits and aboveground plant biomass in shrub‐ and grass‐dominated community in desert steppe
Authors: Zhao Shenglong , Zhang Tonghui , Yue Ping , Lv Peng , Hu Ya , Medina‐Roldán Eduardo , Zuo Xiaoan
Published: April 2021

Grazing disturbance plays a crucial role in regulating plant community structure and ecosystem function in drylands. However, few studies show that how grazing disturbance affects the relationships between functional traits and aboveground plant biomass (AGB). Here, we presented a comparative result from grazing experiment with three levels of grazing intensities (no grazing, moderate and heavy grazing) between shrub‐ and grass‐dominated community in desert steppe, Inner Mongolia. We measured vegetation characteristics and plant traits (plant height, LT: leaf thickness, SLA: specific leaf area, LDMC: leaf dry matter content, LCC: leaf carbon content and LNC: leaf nitrogen content) in the two communities across 2 years (2017–2018). We used the linear regression analysis and the structural equation modeling (SEM) to examine how grazing affect the associations of AGB with plant traits. We found that grazing decreased vegetation cover, AGB and litter mass in two communities, and caused the differences in AGB among two communities. Heavy grazing eliminated the associations of AGB with SLA and LCC in shrub community, while led to their positive or negative associations in grass community. The SEM showed that grazing indirectly decreased AGB through its effect on LT in shrub community, and its effect on plant height in grass community. These results suggest that changes in leaf traits induced by heavy grazing can explain AGB in grass‐ rather than shrub‐community, thereby possibly contributing to AGB differences between two communities. Indirect effects of increased grazing intensities on AGB in shrub or grass community are dependent on specific functional traits.
Sob gene is critical to wing development in Bombyx mori and Tribolium castaneum
Authors: Ye Zhan‐Feng , Zhang Pan , Gai Ting‐Ting , Lou Jing‐Hou , Dai Fang‐Yin , Tong Xiao‐Ling
Published: April 2021

The development of insect appendages requires the expression of multiple genes in a strict spatial and temporal order. The odd‐skipped family genes are vital transcriptional factors involved in embryonic development. The development and morphogenesis of the insect wing requires multiple transcription factors to regulate the expression of wing patterning genes at the transcriptional level. However, the function of odd‐related genes in insect wing morphogenesis and development during postembryonic stages is unclear. We focused on the roles of the sister of odd and bowl (sob) gene, a member of odd‐skipped family genes, during the wing morphopoiesis in Bombyx mori using the clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR‐associated protein 9 system and in Tribolium castaneum by RNA interference. The results showed that the wings were significantly smaller and degenerated, and wing veins were indistinct in the sob gene loss‐of‐function group in both B. mori and T. castaneum. Quantitative real‐time polymerase chain reaction revealed that the Tcsob gene regulated the expression of wing development genes, such as the cht 7 and the vg gene. The findings suggest the importance of sob gene in insect wing morphology formation during postembryonic stages.
Differentiation and classification of Chinese Luzhou‐flavor liquors with different geographical origins based on fingerprint and chemometric analysis
Authors: Qian Yu , Zhang Liang , Sun Yue , Tang Yongqing , Li Dan , Zhang Huaishan , Yuan Siqi , Li Jinsong
Published: April 2021

In order to differentiate and characterize Chinese Luzhou‐flavor liquor according to geographical origins, the volatile flavor compounds were analyzed for forty commercial Luzhou‐flavor liquor samples from Sichuan, Jiangsu, and Hubei provinces. A total of 113 volatile flavor compounds were quantified; among them, 29 flavor compounds were quantified according to the internal standard method. The differences in flavor composition among different brands of Luzhou‐flavor liquor were compared. A data matrix of 64 (flavor components) × 40 (samples) was studied and interpreted using chemometric analysis. The research object could be naturally clustered according to geographical origin (brand) based on the hierarchical cluster analysis (HCA), principal component analysis (PCA) and multivariate analysis of variance (MANOVA) methods. A 100% of predication ability was obtained by the application of K‐nearest neighbor model (KNN) for study sample classification. The results demonstrate that the abundance of volatile flavor components in liquors combined with appropriate multivariate statistical methods could be used for the division and traceability of liquors from different geographic origins.

Practical Application

This study can provide the basis for the identification of liquor authenticity and the traceability of liquor.
Merging computational fluid dynamics and machine learning to reveal animal migration strategies
Authors: Olivetti Simone , Gil Michael A. , Sridharan Vamsi K. , Hein Andrew M.
Published: April 2021

Understanding how migratory animals interact with dynamic physical environments remains a major challenge in migration biology. Interactions between migrants and wind and water currents are often poorly resolved in migration models due to both the lack of high‐resolution environmental data, and a lack of understanding of how migrants respond to fine‐scale structure in the physical environment.

Here we develop a generalizable, data‐driven methodology to study the migration of animals through complex physical environments. Our approach combines validated computational fluid dynamic (CFD) modelling with animal tracking data to decompose migratory movements into two components, namely movement caused by physical forcing and movement due to active locomotion. We then use a flexible recurrent neural network model to relate local environmental conditions to locomotion behaviour of the migrating animal, allowing us to predict a migrant's force production, velocity and trajectory over time.

We apply this framework to a large dataset containing measured trajectories of migrating Chinook salmon through a section of river in California's Sacramento‐San Joaquin Delta. We show that the model is capable of describing fish migratory movements as a function of local flow variables, and that it is possible to accurately forecast migratory movements on which the model was not trained.

After validating our model, we show how our framework can be used to understand how migrants respond to local‐flow conditions, how migratory behaviour changes as overall conditions in the system change and how the energetic cost of migratory movements depends on environmental conditions in space and time. Our framework is flexible and can readily be applied to other species and systems.