bluuebunny/crossref_metadata_2025 huggingface dataset:
Perturbation of transmembrane 6 superfamily member 2 expression alters lipid metabolism in a human liver cell line
Authors: Pant Asmita , Chen Yue , Kuppa Annapurna , Du Xiaomeng , Halligan Brian D , Speliotes Elizabeth K
Published: August 2021

Background

Nonalcoholic fatty liver disease (NAFLD) is caused by accumulation of excess lipids in hepatocytes. Genome wide association studies have identified strong association of NAFLD with non-synonymous E167K amino acid mutation in transmembrane 6 superfamily member 2 (TM6SF2) protein. The E167K mutation affects TM6SF2 stability and its carriers display increased hepatic lipids levels and lower serum triglycerides. While similar phenotype is evident in mice with TM6SF2 knockdown, effects of TM6SF2 on hepatic lipid metabolism is not completely understood.

Methods

Here, we overexpressed wild-type or E167K variant of TM6SF2 or knocked down TM6SF2 expression in lipid-treated Huh-7 cells and used biochemical assays, untargeted lipidomic analysis, RNAseq transcriptome analysis and high-throughput fluorescent imaging to determine changes in lipid metabolism.

Results

Both knockdown and E167K overexpression increased acylglyceride levels which was decreased by wild-type TM6SF2 overexpression. Further, mean intensity of individual lipid droplets was increased by E167K overexpression and knockdown while wild-type TM6SF2 had no effects. We also observed lipid chain remodeling for acylglycerides by TM6SF2 knockdown leading to a relative increase in species with shorter and more saturated side chains. RNA sequencing revealed differential expression of several lipid metabolizing genes, including genes belonging to AKR1 family and lipases, primarily in cells with TM6SF2 knockdown.

Conclusion

Taken together, our data shows that overexpression of TM6SF2 gene or its loss-of-function changes hepatic lipid species composition and expression of lipid metabolizing genes. Further, overexpression of E167K variant and TM6SF2 knockdown similarly increased hepatic lipid accumulation and lipid droplets profile further confirming a loss-of-function effect for variant.
A Self-Limiting Circuit Regulates Mammary Cap Cell Plasticity Through TGF-beta Signaling
Authors: Le Guelte Armelle , Macara Ian G.
Published: August 2021

The organization and maintenance of complex tissues requires emergent properties driven by self-organizing and self-limiting cell-cell interactions. We examined these interactions in the murine mammary gland. Luminal and myoepithelial subpopulations of the postnatal mammary gland arise from unipotent progenitors, but the destiny of cap cells, which enclose terminal end buds (TEB) in pubertal mice, remains controversial. Using a transgenic strain (Tg11.5kb-GFP) that specifically marks cap cells, we found ~50% of these cells undergo divisions perpendicular to the TEB surface, suggesting they might contribute to the underlying luminal cell population. To address their stemness potential we developed a lineage tracing mouse driven from the s-SHIP (11.5 kb) promoter. Induction of tdTomato (tdTom) from this promoter in vivo demonstrated that all cap cell progeny are myoepithelial, with no conversion to luminal lineage. Organoid cultures also exhibited unipotency. However, isolated cap cells cultured as mammospheres generated mixed luminal/myoepithelial spheres. Moreover, ablation of luminal cells in vivo using diphtheria toxin triggered repopulation by progeny of tdTom+ cap cells. A signaling inhibitor screen identified the TGFβ pathway as a potential regulator of multipotency. TGFβR inhibitors or gene deletion blocked conversion to the luminal lineage, consistent with an autocrine loop in which cap cells secrete TGFβ to activate the receptor and promote luminal transdifferentiation. Ductal tree regeneration in vivo from isolated cap cells was much more efficient when they were pre-treated with inhibitor, consistent with more cells retaining cap cell potential prior to transplantation. Notably, in vitro transdifferentiation of cap cells was blocked by co-culture with luminal cells. Overall, these data reveal a self-limiting cell circuit through which mammary luminal cells suppress cap cell conversion to the luminal lineage.
Extraction and high-throughput sequencing of oak heartwood DNA: assessing the feasibility of genome-wide DNA methylation profiling
Authors: Rossi Federico , Crnjar Alessandro , Comitani Federico , Feliciano Rodrigo , Jahn Leonie , Malim George , Southgate Laura , Kay Emily , Oakey Rebecca , Buggs Richard , Moir Andy , Kistler Logan , Mateos Ana Rodriguez , Molteni Carla , Schulz Reiner
Published: August 2021

Tree ring features are affected by environmental factors and therefore are the basis for dendrochronological studies to reconstruct past environmental conditions. Oak wood often provides the data for these studies because of the durability of oak heartwood and hence the availability of samples spanning long time periods of the distant past. Wood formation is regulated in part by epigenetic mechanisms such as DNA methylation. Studies of the methylation state of DNA preserved in oak heartwood thus could identify epigenetic tree ring features informing on past environmental conditions. In this study, we aimed to establish protocols for the extraction of DNA, the high-throughput sequencing of whole-genome DNA libraries (WGS) and the profiling of DNA methylation by whole-genome bisulfite sequencing (WGBS) for oak (Quercus spp.) heartwood drill cores taken from the trunks of living standing trees spanning the AD 1776-2014 time period. Heartwood contains little DNA, and large amounts of phenolic compounds known to hinder the preparation of high-throughput sequencing libraries. Whole-genome and DNA methylome library preparation and sequencing consistently failed for oak heartwood samples more than 100 and 50 years of age, respectively. DNA fragmentation increased with sample age and was exacerbated by the additional bisulfite treatment step during methylome library preparation. Relative coverage of the non-repetitive portion of the oak genome was sparse. These results suggest that quantitative methylome studies of oak hardwood will likely be limited to relatively recent samples and will require a high sequencing depth to achieve sufficient genome coverage.
IMMMUNE MEDIATORS IN IDIOPATHIC UVEITIS
Authors: Errera Marie-Hélène , Pratas Ana , Fisson Sylvain , Manicom Thomas , Boubaya Marouane , Sedira Neila , Héron Emmanuel , Merabet Lilia , Kobal Alfred , Levy Vincent , Warnet Jean-Michel , Chaumeil Christine , Brignole-Baudouin Françoise , Sahel José-Alain , Goldschmidt Pablo , Bodaghi Bahram , Bloch-Queyrat Coralie
Published: August 2021

To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis were analyzed by multiplex immunoassay. Infectious controls consisted of 16 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. Noninfectious controls consisted of 7 patients with Behçet disease related uveitis and 15 patients with sarcoidosis related uveitis. The control group consisted of AH and serum samples from 47 noninflammatory control patients with age-related cataract. In each sample, 27 immune mediators ± IL-21 and IL-23 were measured. In idiopathic uveitis, 13 of the 29 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-12, G-CSF, GM-CSF, MCP-1, IP-10, TNF-α and VEGF, were significantly elevated in the aqueous humor when compared to all controls. Moreover, IL-17, IP-10, and IL-21, were significantly elevated in the serum when compared to all controls. We clustered 4 subgroups of idiopathic uveitis using a statistical analysis of hierarchical unsupervised classification, characterized by the order of magnitude of concentrations of intraocular cytokines. The pathogenesis of idiopathic uveitis is characterized by the presence of predominantly proinflammatory cytokines and chemokines and vascular endothelial growth factor with high expression levels as compared to other causes of uveitis. There are indications for obvious Th-1/ IL21-Th17 pathways but also IL9-Th9 and increased IFN-γ-inducing cytokine (IL12) and IFN-γ-inducible CXC chemokine (IP-10). The combined data suggest that immune mediator expression is different among idiopathic uveitis. This study suggests various clusters among the idiopathic uveitis group rather than one specific uveitis entity.
Gender identity and sexual experience affect mating behaviour and chemical profile in the lesser mealworm,Alphitobius diaperinus(Coleoptera: Tenebrionidae)
Authors: Calla-Quispe Erika , Martel Carlos , Ibañez Alfredo J.
Published: August 2021

Alphitobius diaperinus(Coleoptera: Tenebrionidae), the lesser mealworm, is one of the most significant pests of the poultry industry worldwide. These insects cause structural damage in poultry houses and transmit several diseases, impacting chickens’ productivity and rearing costs. Although semiochemicals may offer alternative insect pest management strategies, basic information regarding pheromone identity and their role on the behavioural ecology according to their circadian pattern of sexual behaviour ofA. diaperinusis essentially lacking. This study is aimed to analyse the relation of gender identity and sexual experience of adults ofA. diaperinuson their mating behaviour and whether this response is related to their CHC profiles secreted. The following steps were taken to achieve the study’s goal. First, the circadian pattern of their sexual activity was observed in newly emerged pairs for at least twenty-one days (virgin adults) and experienced adults collected from the field to identify a difference based on their sexual experience and achieve the optimal mating season to develop the following assays. Subsequently, Y-tube olfactometer bioassays were conducted to evaluate their odour bouquet attraction based on gender and sexual experience. Additionally, mating behaviour bioassays were conducted to evaluate the two factor effects. Finally, cuticular analysis was performed using gas chromatography-mass spectrometry to evaluate possible chemical differences based on the two factors. With statistical and multivariate analysis, we found that behavioural, mating and chemical responses are different based on their sexual experience. The mating sequences were described into precopulatory, copulatory and postcopulatory phases. This finding gives us a deeper understanding of the sexual communication during mating. In summary, our findings provide new insights into the mating system and chemical ecology ofA. diaperinus. The results presented here may serve as a base for further studies to develop strategies for managing this pest.
The complete mitogenome of Lysmata vittata (Crustacea: Decapoda: Hippolytidae) and its phylogenetic position in Decapoda
Authors: Zhu Longqiang , Zhu Zhihuang , Zhu Leiyu , Wang Dingquan , Wang Jianxin , Lin Qi
Published: August 2021

In this study, the complete mitogenome of Lysmata vittata (Crustacea: Decapoda: Hippolytidae) has been determined. The genome sequence was 22003 base pairs (bp) and it included thirteen protein-coding genes (PCGs), twenty-two transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs) and three putative control regions (CRs). The nucleotide composition of AT was 71.50%, with a slightly negative AT skewness (−0.04). Usually the standard start codon of the PCGs was ATN, while cox1, nad4L and cox3 began with TTG, TTG and GTG. The canonical termination codon was TAA, while nad5 and nad4 ended with incomplete stop codon T, and cox1 ended with TAG. We compared the order of genes of Decapoda ancestor and found that the positions of the two tRNAs genes (trnA and trnR) of the L. vittata were translocated. The phylogenetic tree showed that L. vittata was an independent clade, namely Hippolytidae.
The role of artificial photo backgrounds of shelter dogs on pet profile clicking and the perception of sociability
Authors: Lamb F , Andrukonis A , Protopopova A
Published: August 2021

With the increasing prevalence of technology, the internet is often the first step for potential pet owners searching for an adoptable dog. However, best practices for the online portrayal of shelter and foster dogs remain unclear. Different online photo backgrounds appearing on adoption websites for shelter dogs may impact adoption speed by influencing viewer interest. Online clicking behaviour on pet profiles and human-directed sociability, broadly defined, has been previously linked to increased adoption likelihood. Therefore, the objective of this study was to determine the relationship between photo backgrounds of shelter dogs and online clicking as well as perceived human-directed sociability. In a virtual experiment, 680 participants were asked to rank the sociability and friendliness of four different adoptable dogs on a scale from 0-10. The photo background of each dog was digitally altered and randomly assigned to four experimental background conditions: 1) outdoor, 2) home indoor, 3) in-kennel indoor, and 4) plain coloured. As a proxy for adoption interest, a link to the dog’s adoption profile was presented on each slide and the clicking behaviour of participants on this link was recorded. Mixed logistic regression and poisson models revealed that background did not affect participants’ link-clicking behaviour (chisq = 3.55, df = 3, p = .314) nor perceptions of sociability (statistic = 6.19, df = 3, p = .103). Across all backgrounds, only 4.74% of presented slides culminated in participant link-clicking. Sociability scores also did not predict link clicking. Assessment of participant-related factors and dog ID revealed that link-clicking and sociability scores of photographs were influenced by differences between dogs themselves and unaffected by participants’ awareness of study hypotheses. We conclude that artificial background types did not affect participant responses. The results demonstrate the importance of empirical data in making marketing decisions in animal shelters. Understanding which aspects of online marketing materials impact viewer interest will provide guidance for both animal shelter personnel and foster families to improve speed of adoption of the animals in their care.
Reaching articular limits can negatively impact embodiment in virtual reality
Authors: Porssut Thibault , Blanke Olaf , Herbelin Bruno , Boulic Ronan
Published: August 2021

Providing Virtual Reality(VR) users with a 3D representation of their body complements the experience of immersion and presence in the virtual world with the experience of being physically located and more personally involved. A full-body avatar representation is known to induce a Sense of Embodiment (SoE) for this virtual body, which is associated with improvements in task performance, motivation and motor learning. Recent experimental research on embodiment provides useful guidelines, indicating the extent of discrepancy tolerated by users and, conversely, the limits and disruptive events that lead to a break in embodiment (BiE). Based on previous works on the limit of agency under movement distortion, this paper describes, studies and analyses the impact of a very common yet overlooked embodiment limitation linked to articular limits when performing a reaching movement. We demonstrate that perceiving the articular limit when fully extending the arm provides users with an additional internal proprioceptive feedback which, if not matched in the avatar’s movement, leads to the disruptive realization of an incorrect posture mapping. This study complements previous works on self-contact and visuo-haptic conflicts and emphasizes the risk of disrupting the SoE when distorting users’ movements or using a poorly-calibrated avatar.
Development and evaluation of a decision prediction tool for the reduction of fungicide applications for the control of strawberry powdery mildew epidemics
Authors: Dodgson Jolyon L. A. , Liu Bo , Wileman Hannah J. , Mutasa-Gottgens Euphemia S , Hall Avice M.
Published: August 2021

Strawberry powdery mildew (Podosphaera aphanis) causes serious losses in UK crops, potentially reducing yields by as much as 70%. Consequently, conventional fungicide application programmes tend to recommend a prophylactic approach using insurance sprays, risking the development of fungicide insensitivity and requiring careful management relative to harvest periods to avoid residual fungicides on harvested fruit. This paper describes the development of a prediction system to guide the control of P. aphanis by the application of fungicides only when pathogen infection and disease progression are likely. The system was developed over a 15-year period on commercial farms starting with its establishment, validation and then deployment to strawberry growers. This involved three stages: 1. Identification and validation of parameters for inclusion in the prediction system (2004-2008). 2. Development of the prediction system in compact disc format (2009-2015). 3. Development and validation of the prediction system in a web-based format and cost-benefit analysis (2016-2020). The prediction system was based on the temporal accumulation of conditions (temperature and relative humidity) conducive to the development of P. aphanis, which sporulates at 144 accumulated disease-conducive hours. Sensitivity analysis was performed to refine the prediction system parameters. Field validation of the results demonstrated that to effectively control disease, the application of fungicides was best done between 125 and 144 accumulated hours of disease-conducive conditions. A cost-benefit analysis indicated that, by comparison with the number and timing of fungicide applications in conventional insurance disease control programmes, the prediction system enabled good disease control with significantly fewer fungicide applications (between one and four sprays less) (df=7, t=7.6, p=0.001) and reduced costs (savings between £35-£493/hectare) (df=7, t=4.0, p=0.01) for the growers.
Low-level overexpression of wild type TDP-43 causes late-onset, progressive neurodegeneration and paralysis in mice
Authors: Yang Chunxing , Qiao Tao , Yu Jia , Wang Hongyan , Guo Yansu , Salameh Johnny , Metterville Jake , Parsi Sepideh , Brown Robert H. , Cai Huaibin , Xu Zuoshang
Published: August 2021

Modestly increased expression of transactive response DNA binding protein (TDP-43) gene have been reported in amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and other neuromuscular diseases. However, whether this modest elevation triggers neurodegeneration is not known. Although high levels of TDP-43 overexpression have been modeled in mice and shown to cause early death, models with low-level overexpression that mimic the human condition have not been established. In this study, transgenic mice overexpressing wild type TDP-43 at less than 60% above the endogenous CNS levels were constructed, and their phenotypes analyzed by a variety of techniques, including biochemical, molecular, histological, behavioral techniques and electromyography. The TDP-43 transgene was expressed in neurons, astrocytes, and oligodendrocytes in the cortex and predominantly in astrocytes and oligodendrocytes in the spinal cord. The mice developed a reproducible progressive weakness ending in paralysis in mid-life. Detailed analysis showed ∼30% loss of large pyramidal neurons in the layer V motor cortex; in the spinal cord, severe demyelination was accompanied by oligodendrocyte injury, protein aggregation, astrogliosis and microgliosis, and elevation of neuroinflammation. Surprisingly, there was no loss of lower motor neurons in the lumbar spinal cord despite the complete paralysis of the hindlimbs. However, denervation was detected at the neuromuscular junction. These results demonstrate that low-level TDP-43 overexpression can cause diverse aspects of ALS, including late-onset and progressive motor dysfunction, neuroinflammation, and neurodegeneration. Our findings suggest that persistent modest elevations in TDP-43 expression can lead to ALS and other neurological disorders involving TDP-43 proteinopathy. Because of the predictable and progressive clinical paralytic phenotype, this transgenic mouse model will be useful in preclinical trial of therapeutics targeting neurological disorders associated with elevated levels of TDP-43.
Allelopathy as an evolutionarily stable strategy
Authors: McCoy Rachel M. , Widhalm Joshua R. , McNickle Gordon G.
Published: August 2021

In plants, most competition is resource competition, where one plant simply pre-empts the resources away from its neighbours. Interference competition, as the name implies, is a form of direct interference to prevent resource access. Interference competition is common among animals who can physically fight, but in plants, one of the main mechanisms of interference competition is Allelopathy. allelopathic plants release of cytotoxic chemicals into the environment which can increase their ability to compete with surrounding organisms for limited resources. The circumstances and conditions favoring the development and maintenance of allelochemicals, however, is not well understood. Particularly, it seems strange that, despite the obvious benefits of allelopathy, it seems to have only rarely evolved. To gain insight into the cost and benefit of allelopathy, we have developed a 2 × 2 matrix game to model the interaction between plants that produce allelochemicals and plants that do not. Production of an allelochemical introduces novel cost associated with synthesis and detoxifying a toxic chemical but may also convey a competitive advantage. A plant that does not produce an allelochemical will suffer the cost of encountering one. Our model predicts three cases in which the evolutionarily stable strategies are different. In the first, the non-allelopathic plant is a stronger competitor, and not producing allelochemicals is the evolutionarily stable strategy. In the second, the allelopathic plant is the better competitor and production of allelochemicals is the more beneficial strategy. In the last case, neither is the evolutionarily stable strategy. Instead, there are alternating stable states, depending on whether the allelopathic or non-allelopathic plant arrived first. The generated model reveals circumstances leading to the evolution of allelochemicals and sheds light on utilizing allelochemicals as part of weed management strategies. In particular, the wide region of alternative stable states in most parameterizations, combined with the fact that the absence of allelopathy is likely the ancestral state, provides an elegant answer to the question of why allelopathy rarely evolves despite its obvious benefits. Allelopathic plants can indeed outcompete non-allelopathic plants, but this benefit is simply not great enough to allow them to go to fixation and spread through the population. Thus, most populations would remain purely non-allelopathic.
uPIC–M: efficient and scalable preparation of clonal single mutant libraries for high-throughput protein biochemistry
Authors: Appel Mason J. , Longwell Scott A. , Morri Maurizio , Neff Norma , Herschlag Daniel , Fordyce Polly M.
Published: August 2021

New high-throughput biochemistry techniques complement selection-based approaches and provide quantitative kinetic and thermodynamic data for thousands of protein variants in parallel. With these advances, library generation rather than data collection has become rate limiting. Unlike pooled selection approaches, high-throughput biochemistry requires mutant libraries in which individual sequences are rationally designed, efficiently recovered, sequence-validated, and separated from one another, but current strategies are unable to produce these libraries at the needed scale and specificity at reasonable cost. Here, we present a scalable, rapid, and inexpensive approach for creating User-designed Physically Isolated Clonal–Mutant (uPIC–M) libraries that utilizes recent advances in oligo synthesis, high-throughput sample preparation, and next-generation sequencing. To demonstrate uPIC–M, we created a scanning mutant library of SpAP, a 541 amino acid alkaline phosphatase, and recovered 94% of desired mutants in a single iteration. uPIC–M uses commonly available equipment and freely downloadable custom software and can produce a 5000 mutant library at 1/3 the cost and 1/5 the time of traditional techniques.
Opposing roles of p38α-mediated phosphorylation and arginine methylation in driving TDP-43 proteinopathy
Authors: Aikio Mari , Wobst Heike J. , Odeh Hana M. , Lee Bo Lim , Class Bradley , Ollerhead Thomas A. , Mack Korrie L. , Ford Alice F. , Barbieri Edward M. , Cupo Ryan R. , Drake Lauren E. , Castello Nicholas , Baral Ashmita , Dunlop John , Gitler Aaron D. , Javaherian Ashkan , Finkbeiner Steven , Brown Dean G. , Moss Stephen J. , Brandon Nicholas J. , Shorter James
Published: August 2021

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder typically characterized by insoluble inclusions of hyperphosphorylated TDP-43. The mechanisms underlying toxic TDP-43 accumulation are not understood. Persistent activation of p38 mitogen-activated protein kinase (MAPK) is implicated in ALS. However, it is unclear how p38 MAPK affects TDP-43 proteinopathy. Here, we demonstrate that inhibition of p38α MAPK reduces pathological TDP-43 phosphorylation, aggregation, cytoplasmic mislocalization, and neurotoxicity. We establish that p38α MAPK phosphorylates TDP-43 at pathological serine 409/410 (S409/S410) and serine 292 (S292), which reduces TDP-43 liquid-liquid phase separation (LLPS) but allows pathological TDP-43 aggregation. Moreover, we show that protein arginine methyltransferase 1 methylates TDP-43 at R293. Importantly, S292 phosphorylation reduces R293 methylation, and R293 methylation reduces S409/S410 phosphorylation. R293 methylation permits TDP-43 LLPS and reduces pathological TDP-43 aggregation. Thus, strategies to reduce p38α-mediated TDP-43 phosphorylation and promote R293 methylation could have therapeutic utility for ALS and related TDP-43 proteinopathies.
Mathematical Relationships between Spinal Motoneuron Properties
Authors: Caillet Arnault , Phillips Andrew T.M. , Farina Dario , Modenese Luca
Published: August 2021

Our understanding of the behaviour of spinal alpha-motoneurons (MNs) in mammals partly relies on our knowledge of the relationships between MN membrane properties, such as MN size, resistance, rheobase, capacitance, time constant, axonal conduction velocity and afterhyperpolarization period.

We reprocessed the data from 40 experimental studies in adult cat, rat and mouse MN preparations, to empirically derive a set of quantitative mathematical relationships between these MN electrophysiological and anatomical properties. This validated mathematical framework, which supports past findings that the MN membrane properties are all related to each other and clarifies the nature of their associations, is besides consistent with the Henneman’s size principle and Rall’s cable theory.

The derived mathematical relationships provide a convenient tool for neuroscientists and experimenters to complete experimental datasets, to explore relationships between pairs of MN properties never concurrently observed in previous experiments, or to investigate inter-mammalian-species variations in MN membrane properties. Using this mathematical framework, modelers can build profiles of inter-consistent MN-specific properties to scale pools of MN models, with consequences on the accuracy and the interpretability of the simulations.
Comparison of different fidelity mass analyses
Authors: Mieloszyk Jacek , Tarnowski Andrzej , Goetzendorf-Grabowski Tomasz , Kowalski Mariusz , Goliszek Bartłomiej
Published: August 2021

Purpose

Aircraft structure mass estimation is a very important issue in aerospace. Multiple methods of different fidelity are available, which give results with varying accuracy. Sometimes these methods are giving a high discrepancy of estimated mass compared to the real mass of the structure. The discrepancy is especially noticeable in the case of small aircraft with a composite structure. Their mass properties highly depend not only on the material but also on technology and the human factor. Moreover, methods of mass estimation for unmanned aerial vehicle (UAV) platforms are even less established and examined. The purpose of this paper is to present and discuss various methods of mass estimation.

Design/methodology/approach

The paper presents different procedures of mass estimation for small UAVs with a composite structure. Beginning from the simplest one, where mass is estimated basing on a single equation and finishing with a mass estimation based on finite element method model and three-dimensional computer-aided design model. The results from all methods are compared with the airworthy aircraft and conclusions are discussed.

Findings

Mass of flying aircraft was estimated with different methods and compared. It revealed levels of accuracy of the investigated methods. Moreover, the influence on structure mass of human factor, glueing and painting is underlined.

Practical implications

Mass of the structure is a key factor in aerospace, which influences the performance of the aircraft. Thorough knowledge about the accuracy of the mass estimation methods and possible sources of discrepancies in mass analyses provides an essential tool for designers, which can be used with confidence and allows for the development of new cutting-edge constructions.

Originality/value

There are very few comparisons of mass estimation methods with an actual mass of manufactured and functional airframes. Additionally, mass estimation inaccuracies based on technological issues are presented, which is seldom done.
Performance of a microjet using component map scaling
Authors: Coban Kahraman , Ekici Selcuk , Colpan Can Ozgur , Karakoç Tahir Hikmet
Published: August 2021

Purpose

This paper aims to investigate the cycle performance of a small size turbojet engine used in unmanned aerial vehicles at 0–5,000 m altitude and 0–0.8 Mach flight speeds with real component maps.

Design/methodology/approach

The engine performance calculations were performed for both on-design and off-design conditions through an in-house code generated for simulating the performance of turbojet engines at different flight regimes. These calculations rely on input parameters in which fuel composition are obtained through laboratory elemental analysis.

Findings

Exemplarily, according to comparative results between in-house developed performance code and commercially available software, there is 0.25% of the difference in thrust value at on-design conditions.

Practical implications

Once the on-design performance parameters and fluid properties were determined, the off-design operation calculations were performed based on the compressor and turbine maps and scaling methodology. This method enables predicting component maps and fitting them to real conditions.

Originality/value

A method to be used easily by researchers on turbojet engine performance calculations which best fits to real conditions.
The impact of strategic competitive innovation on the financial performance of SMEs during COVID-19 pandemic period
Authors: El Chaarani Hani , Vrontis Prof. Demetris , El Nemar Sam , El Abiad Zouhour
Published: August 2021

Purpose

The purpose of this paper is to reveal the impact of strategic competitive innovation types on the financial performance of SMEs during a very critical period: the COVID-19 pandemic. Four strategic competitive innovation types are considered in this study: marketing innovation, organizational innovation, product innovation and processes innovation.

Design/methodology/approach

To examine empirically the relationship between strategic competitiveness and financial performance, data were collected from a sample of 426 Lebanese SMEs belonging to seven different sectors.

Findings

The empirical findings of principle component analysis model (PCA) and multiple regression model (MR) reveal that the ability to innovate is essential to an SME’s survival during a crisis. The results of this study confirm the existence of a positive impact of marketing innovation and processes innovation on the financial performance of SMEs during the COVID-19 pandemic.

Practical implications

Moreover, results suggest that, in Lebanese SMEs, product innovation and organizational innovation do not have any impact on the financial performance during the pandemic period.

Originality/value

This research focused on strategic competitive innovation as a broadly considered essential condition for the survival of SMEs during the COVID-19 crises.
The learning organization: the time is ripe for starting to certify the idea
Authors: Örtenblad Anders
Published: August 2021

Purpose

To convince readers that the time is ripe to start certifying the learning organization and to outline what would be needed to accomplish such a certification.

Design/methodology/approach

This is an argumentative piece based on the author’s almost 30 years of experience from researching and authoring the learning organization.

Findings

It is argued that the idea of the learning organization is still “fluffy” and that it is not universally applicable as is. It is suggested that a broad, inclusive definition of the learning organization is taken as the starting point for the process of contextualizing the idea to reach a set of “contextualized standards”, which could be used when certifying the learning organization.

Research limitations/implications

Researchers are encouraged – in cooperation with practitioners – to sculpture one “contextualized standard” of the learning organization for each single industry. Such contextualized standards outline what, exactly, that could be demanded from organizations within the particular industry that want to become learning organizations.

Practical implications

There is a need for one – or some – non-profit association/s that could start to certify the learning organization on the basis of a set of contextualized standards. There may also be a need for consultants assisting organizations to transform themselves into learning organizations in accordance with these contextualized standards.

Originality/value

This is the first time (at least in writing) that it is suggested that the learning organization is certified.
How different rewards tend to influence employee non-compliance with information security policies
Authors: Khatib Rima , Barki Henri
Published: August 2021

Purpose

To help reduce the increasing number of information security breaches that are caused by insiders, past research has examined employee non-compliance with information security policy. However, existent studies have observed mixed results, which suggest that an interaction is likely to exist among the variables that explain employee non-compliance. In an effort to provide evidence for this possibility, this paper aims to better explain why employees routinely engage in non-compliant behaviors by examining the direct and interactive effects of employees’ perceived costs and rewards of compliance and non-compliance on their routinized non-compliant behaviors.

Design/methodology/approach

Based on rational choice theory, this study used 16 hypothetical scenarios in an experimental survey, collecting data from 326 respondents and analyzing them via structural equation modeling and a four-way factorial experiment.

Findings

The results suggest that routinized non-compliance of employees is more strongly influenced by the rewards than the costs they perceive in their non-compliance. Further, employees’ routinized non-compliance behavior was found to be positively influenced by an interactive effect of perceived rewards of compliance when their perceptions of their non-compliance costs and rewards were both high and low.

Originality/value

This paper’s key contribution is to suggest that non-compliance behavior is influenced by direct and interactive effects of perceived rewards of compliance and non-compliance.
Validity of zakat ratios as Islamic performance indicators in Islamic banking: a congeneric model and confirmatory factor analysis
Authors: Nomran Naji Mansour , Haron Razali
Published: August 2021

Purpose

There is much debate in the literature about how the performance of Islamic banks (IBs) should be measured. Basically, IBs’ business models are different from that of conventional banks; thus, the performance of IBs should be measured by using a Sharīʿah-based approach. This paper considers zakat (Islamic tax) as an alternative indicator to measure the performance of IBs. This paper aims to examine whether zakat ratios can be used as Islamic performance (ISPER) indicators for IBs besides the conventional performance (COPER) indicators.

Design/methodology/approach

The investigation covered a sample of 214 yearly observations of 37 IBs located in Indonesia, Malaysia, Bahrain, Saudi Arabia and the United Arab Emirates for the period 2007–2015. This study used a single-factor congeneric model and confirmatory factor analysis, performed using the AMOS 23.0 software.

Findings

The findings assert that the discriminant validity of multi-bank performance, as measured by ISPER [zakat on assets (ZOA) and zakat on equity (ZOE)] and COPER indicators (return on assets, return on equity and operational efficiency in terms of assets), is very high. Hence, ISPER and COPER measurements are valid, either together to measure the multi-performance of IBs from both the Islamic and conventional perspectives, or independently as each measurement is valid to measure the Islamic and conventional performance if it is used separately.

Research limitations/implications

This paper does not investigate whether the findings are constant across time. This represents one of the limitations of this study.

Practical implications

It is strongly recommended that IBs calculate and disclose zakat ratios, particularly ZOA and ZOE, in their annual reports. Researchers and academicians should use these ratios for measuring the ISPER of IBs, either along with COPER or separately.

Originality/value

Empirical evidence is provided in this paper on the development and validity of zakat ratios as ISPER indicators in the Islamic banking industry. Zakat ratios are suitable indicators that can measure IBs’ performance and achieve the goals of IBs as well as those of Islamic economics. Technically, zakat has a dynamic ability to reflect the profitability of IBs. The more the IBs generate profit, the more they pay zakat. Furthermore, the greater the total assets of IBs, the higher the amount of zakat that they should pay. Thus, zakat ratios can be used as profitability measurements as in the case of tax ratios.
A social ecological model (SEM) to exploring barriers of and facilitators to the implementation of opioid agonist treatment (OAT) programmes in prisons
Authors: Komalasari Rita , Wilson Sarah , Haw Sally
Published: August 2021

Purpose

Opioid agonist treatment (OAT) programmes in prisons play a significant role in preventing the human immunodeficiency virus (HIV). Despite its proven effectiveness, both the availability and coverage of prison OAT programmes remain low. This Indonesian study explores facilitators of, and barriers to, the delivery of methadone programmes in prisons using the social ecological model (SEM).

Design/methodology/approach

The study used a qualitative case study approach comprising two prisons with, and one prison without, methadone programmes. Purposive and snowball sampling was used to recruit study participants. In total, 57 in-depth interviews were conducted with prison governors, health-care staff, prison officers and prisoners. Data was analysed thematically.

Findings

The study findings identified facilitators of and barriers to the delivery of prison OAT programmes at all three levels of the SEM as follows: intrapersonal barriers including misperceptions relating to HIV transmission, the harm reduction role of OAT programmes, methadone dependency and withdrawal symptoms; interpersonal barriers such as inflexible OAT treatment processes and the wide availability of illicit drugs in prisons and; social-structural barriers, notably the general lack of resources.

Research limitations/implications

The findings highlight the importance of and overlap between, organisational and inter-personal, as well as intrapersonal factors. Such an approach is particularly important in the context of the implementation and delivery of methadone programmes in low/middle income countries, where the lack of resources is so significant.

Practical implications

Three main strategies for improvement were suggested as follows: the development of comprehensive education and training programmes for prisoners and all prison staff; the re-assessment of practices relating to the delivery of methadone, and a comprehensive review of harm reduction strategy in prisons, that should consider the role of prisoners’ families to increase support for prisoner participation; the re-assessment of prison policies to support the delivery of methadone programmes in prisons.

Social implications

The author suggests that ongoing international support and national drug policies are vital to the continuation and sustainability of methadone programmes in prisons.

Originality/value

This study contributes to the overall evidence base for OAT programmes in middle-income prison contexts.
Knowledge of the Good Samaritan Drug Overdose Act and possession of a naloxone kit among people recently released from prison
Authors: McLeod Katherine E. , Xavier Jessica , Okhowat Ali , Williams Sierra , Korchinski Mo , Young Pamela , Papamihali Kristi , Martin Ruth Elwood , Monaghan Angus , Sharifi Nader , Buxton Jane A.
Published: August 2021

Purpose

This study aims to describe knowledge of Canada’s Good Samaritan Drug Overdose Act (GSDOA) and take home naloxone (THN) training and kit possession among people being released from provincial correctional facilities in British Columbia.

Design/methodology/approach

The authors conducted surveys with clients of the Unlocking the Gates Peer Health Mentoring program on their release. The authors compared the characteristics of people who had and had not heard of the GSDOA and who were in possession of a THN kit.

Findings

In this study, 71% people had heard of the GSDOA, and 55.6% were in possession of a THN kit. This study found that 99% of people who had heard of the GSDOA indicated that they would call 911 if they saw an overdose. Among people who perceived themselves to be at risk of overdose, 28.3% did not have a THN kit. Only half (52%) of participants had a mobile phone, but 100% of those with a phone said they would call 911 if they witnessed an overdose.

Originality/value

The authors found that people with knowledge of the GSDOA were likely to report that they would call 911 for help with an overdose. Education about the GSDOA should be a standard component of naloxone training in correctional facilities. More than one in four people at risk of overdose were released without a naloxone kit, highlighting opportunities for training and distribution. Access to a cellphone is important in enabling calls to 911 and should be included in discharge planning.
Does the second wave of COVID-19 undermine corporate immunity? International evidence
Authors: Hoang Huy Viet , Nguyen Cuong , Hoang Khanh
Published: August 2021

Purpose

This study compares the impact of the COVID-19 pandemic on stock returns in the first two waves of infection across selected markets, given built-in corporate immunity before the global outbreak.

Design/methodology/approach

The data are collected from listed firms in five markets that have experienced the second wave of COVID-19 contagion, namely the United States (US), Australia, China, Hong Kong and South Korea. The period of investigation in this study ranges from January 24 to August 28, 2020 to cover the first two COVID-19 waves in selected markets. The study estimates the research model by employing the ordinary least square method with fixed effects to control for the heterogeneity that may confound the empirical outcomes.

Findings

The analysis reveals that firms with larger size and more cash reserves before the COVID-19 outbreak have better stock performance under the first wave; however, these advantages impede stock resilience during the second wave. Corporate governance practices significantly influence stock returns only in the first wave as their effects fade when the second wave emerges. The results also suggest that in economies with greater power distance, although stock price depreciation was milder in the first wave, it is more intense when new cases again surge after the first wave was contained.

Practical implications

This paper provides practical implications for corporate managers, policymakers and governments concerning crisis management strategies for COVID-19 and future pandemics.

Originality/value

This study is the first to evaluate built-in corporate immunity before the COVID-19 shock under successive contagious waves. Besides, this study accentuates the importance of cultural understanding in weathering the ongoing pandemic across different markets.
Using real-world engagements for sustainability learning in ODeL in the Global South: challenges and opportunities
Authors: Pretorius Rudi Wessel , Carow Sanet , Wilson Graeme , Schmitz Peter
Published: August 2021

Purpose

This paper aims to showcase and critically review the value of selected pedagogies in which real-world engagements are used to enhance sustainability learning in an open, distance and e-learning (ODeL) context in the Global South. The paper considers opportunities, issues, alternatives and implementation guidelines.

Design/methodology/approach

The School of Ecological and Human Sustainability (University of South Africa) serves as case study, with blended and fully online learning used as examples of pedagogies. The assessment of these pedagogies uses examples of learning activities and exercises, critical reflections on feedback by lecturers and students and consideration against criteria for real-world learning.

Findings

The experiences showcased illustrate that despite challenges in ODeL, real-world engagements can be used successful as pedagogy for sustainability learning in the Global South context. Limited access to ICTs can be mitigated through mobile technologies and free and open software applications, as illustrated by the examples in this paper.

Research limitations/implications

The case study approach and qualitative methodology present limitations, with focus on only two examples. However, significant depth is achieved with the assessment of these examples, while the recommendations and lessons learnt can be applied in other contexts, thus expanding on the knowledge and experience in this field.

Originality/value

This paper showcases innovative approaches to incorporate real-world engagements for sustainability learning in ODeL. Application of real-world engagements in ODeL in the Global South context is original and addresses the need for teaching and learning strategies responding to the digital divide and contributing to expand access to higher education and an Afrocentric discourse to best practice.