bluuebunny/crossref_metadata_2025 huggingface dataset:
New, Innovative, Three-Dimensional In Vivo Model for High-Level Microsurgical and Supermicrosurgical Training: A Replacement for Animal Models
Authors: Pion Eric , Zucal Isabel , Troebs Johannes , Feder Anna-Lena , Kyaw Thura , Khin Sopyay , Heidekrueger Paul I. , Prantl Lukas , Härteis Silke , Aung Thiha
Published: June 2022

Microsurgery and supermicrosurgery are surgical subdomains necessary for a large variety of surgical disciplines. So far, there is no training model for lymphatic surgery or perforator flap surgery, and the most commonly used microsurgical training models are living animals. However, the ethical principles of replacement, refinement, and reduction (the three Rs) of living animals for training purposes were implemented, highlighting the necessity of an animal-sparing microsurgical training model. Formed during embryogenesis, the chick chorioallantoic membrane resembles a highly vascularized, noninnervated membrane within fertilized chicken eggs. The aim of this study was to utilize the chorioallantoic membrane model as an innovative and versatile training model for supermicrosurgery and microsurgery that can reduce the number of animals used for these purposes. The variety of different sized vessels for the implementation of an anastomosis proved the chorioallantoic membrane model as a well-functioning supermicrosurgical and microsurgical training model. The circulatory system is resilient enough to withstand the mechanical stress applied to the tissue, and the patency of the implemented anastomosis can be tested for the verification of the procedures. In summary, the integration of the chorioallantoic membrane model into a surgical training program can benefit its quality by representing a realistic anatomical and physiological model with a high variety of vascular structures. Moreover, the chorioallantoic membrane model satisfies the principles of replacement, refinement, and reduction as an animal-sparing model, indicating the potential of this model as an innovative microsurgical training model for the improvement of surgical skills.
Incidence of Contrast-Associated Acute Kidney Injury in Renal-Competent COVID-19 Patients Undergoing Computed Chest Angiography
Authors: Sedaghat Farzad , Vadvala Harshna V. , Shan Alan , McMahon Michael T. , Gawande Rakhee S.
Published: June 2022

Purpose

COVID-19 infection poses a significant risk of both renal injury and pulmonary embolism, producing a clinical challenge, as the criterion standard examination for pulmonary embolism, computed tomography angiography (CTA), requires the use of nephrotoxic iodinated contrast agents.

Our investigation evaluated whether symptomatic COVID-19–positive patients without laboratory evidence of renal impairment are at increased risk for developing contrast-associated acute kidney injury (CA-AKI).

Method

All COVID-19–positive patients undergoing noncontrast chest computed tomography and CTA at an apex tertiary medical center between March 1 and December 10, 2020, were retrospectively evaluated. A total of 258 renal-competent (estimated glomerular filtration rate >30) patients with baseline and 48- to 72-hour postexamination creatinine measurements were identified and analyzed for incidence of acute kidney injury (AKI) meeting the criteria for CA-AKI.

Results

Twenty-five of 191 patients undergoing CTA (13.1%) and 9 of the 67 undergoing noncontrast computed tomography (13.4%) experienced creatinine increases meeting the criteria for CA-AKI. Univariate and multivariate analyses accounting for known AKI risk factors revealed no correlation between iodinated contrast administration and the incidence AKI meeting the criteria for CA-AKI (univariable odds ratio, 0.97 [95% confidence interval, 0.43–2.20]; multivariable odds ratio, 0.97 [95% confidence interval, 0.40–2.36]).

Conclusions

Renal-competent COVID-19 patients undergoing chest CTA may not have an increased risk of AKI. Additional studies are needed to confirm this preliminary finding.
The pathogenesis of neurologic symptoms of the postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection
Authors: Walitt Brian , Johnson Tory P.
Published: June 2022

Purpose of review

The coronavirus disease 2019 (COVID) pandemic has resulted in significant mortality and morbidity globally. Patients who survive infection may develop continuing disease collectively known as the postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection (PASC), which includes neurologic symptoms especially fatigue and cognitive impairment. The pathogenic mechanisms driving PASC are unknown although a postinfectious process, persistent infection, or lasting pathophysiological changes that occur during acute infection are all suspected to contribute.

Recent findings

Here we review the current evidence underlying potential pathogenic mechanisms of the neurological complications of PASC with particular emphasis on the evidence for postinfectious immune processes and viral persistence.

Immune dysregulation favoring persistent inflammation, including neuroinflammation and enhanced autoimmunity, are present in patients with COVID and likely contribute to the development of PASC. Limited evidence of viral persistence exists but may explain the ongoing inflammatory processes and affinity maturation observed in some patients recovering from COVID infections. No specific studies to date have tied persistent infection to PASC. CNS trauma, in particular hypoxic changes in the CNS, and psychiatric complications occur with greater frequency in patients with COVID and may contribute to the development of PASC. Future research is needed to fully understand the pathophysiological mechanisms driving PASC.
Triggers of migraine: where do we stand?
Authors: Martinelli D. , Pocora M.M. , De Icco R. , Putortì A. , Tassorelli Cristina
Published: June 2022

Purpose of review

In this review, we illustrate and discuss the recent findings regarding the epidemiology and pathophysiology of migraine triggers and their implications in clinical practice.

Recent findings

Data from the literature suggest that individual triggers fail to provoke migraine attack in experimental settings. It is therefore possible that more triggers acting in combination are needed to induce an attack by promoting some degree of brain dysfunction and thus increasing the vulnerability to migraine. Caution is however needed, because some of the factors rated as triggers by the patients may actually be a component of the clinical picture of migraine attacks.

Trigger factors of migraine are endogenous or exogenous elements associated with an increased likelihood of an attack in a short period of time and are reported by up to 75.9% of patients. Triggers must be differentiated from premonitory symptoms that precede the headache phase but do not have a causative role in attack provocation, being rather the very first manifestations of the attack. Identification of real triggers is an important step in the management of migraine. Vice versa, promoting an active avoiding behaviour toward factors whose role as triggers is not certain would be ineffective and even frustrating for patients.
Promoting physical activity for mental health: an updated evidence review and practical guide
Authors: McKeon Grace , Curtis Jackie , Rosenbaum Simon
Published: June 2022

Purpose of review

The aim of this study was to provide psychiatrists with the knowledge, tools and guidance to support physical activity promotion in clinical practice. The review also aims to provide an up-to-date summary of the evidence regarding physical activity in the prevention and treatment of mental disorders in adults.

Recent findings

There is emerging evidence demonstrating that physical activity can protect against incident anxiety and depression. There is robust evidence showing that physical activity is an effective adjunct treatment strategy for depressive disorders and anxiety and stress-related disorders, with emerging evidence for schizophrenia and bipolar disorders. Translation of this evidence into practice is in general ad hoc, and large physical health disparities for people with mental disorders persist. The reasons for this are multifactorial, and include the intersection of social, economic and personal barriers to physical activity. Evidence-based approaches include regular screening of physical activity levels, staff culture change within mental health services and established referral pathways.

Translation of evidence regarding physical activity for mental health into routine programmes is critical. Efforts to move beyond solely targeting individual-level barriers to physical activity and address systemic barriers include lack of access to appropriate exercise services. This requires consideration of training needs, service structure and culture change.
Reversible bacteriophage resistance by shedding the bacterial cell wall
Authors: Ongenae Véronique , Mabrouk Adam Sidi , Crooijmans Marjolein , Rozen Daniel , Briegel Ariane , Claessen Dennis
Published: June 2022

Phages are highly abundant in the environment and pose a major threat for bacteria. Therefore, bacteria have evolved sophisticated defence systems to withstand phage attacks. Here, we describe a previously unknown mechanism by which mono- and diderm bacteria survive infection with diverse lytic phages. Phage exposure leads to a rapid and near-complete conversion of walled cells to a cell-wall-deficient state, which remains viable in osmoprotective conditions and can revert to the walled state. While shedding the cell wall dramatically reduces the number of progeny phages produced by the host, it does not always preclude phage infection. Altogether, these results show that the formation of cell-wall-deficient cells prevents complete eradication of the bacterial population and suggest that cell wall deficiency may potentially limit the efficacy of phage therapy, especially in highly osmotic environments or when used together with antibiotics that target the cell wall.
Live-cell microscopy or fluorescence anisotropy with budded baculoviruses—which way to go with measuring ligand binding to M
4
muscarinic receptors?
Authors: Tahk Maris-Johanna , Torp Jane , Ali Mohammed A. S. , Fishman Dmytro , Parts Leopold , Grätz Lukas , Müller Christoph , Keller Max , Veiksina Santa , Laasfeld Tõnis , Rinken Ago
Published: June 2022

M
4
muscarinic acetylcholine receptor is a G protein-coupled receptor (GPCR) that has been associated with alcohol and cocaine abuse, Alzheimer's disease, and schizophrenia which makes it an interesting drug target. For many GPCRs, the high-affinity fluorescence ligands have expanded the options for high-throughput screening of drug candidates and serve as useful tools in fundamental receptor research. Here, we explored two TAMRA-labelled fluorescence ligands, UR-MK342 and UR-CG072, for development of assays for studying ligand-binding properties to M
4
receptor. Using budded baculovirus particles as M
4
receptor preparation and fluorescence anisotropy method, we measured the affinities and binding kinetics of both fluorescence ligands. Using the fluorescence ligands as reporter probes, the binding affinities of unlabelled ligands could be determined. Based on these results, we took a step towards a more natural system and developed a method using live CHO-K1-hM
4
R cells and automated fluorescence microscopy suitable for the routine determination of unlabelled ligand affinities. For quantitative image analysis, we developed random forest and deep learning-based pipelines for cell segmentation. The pipelines were integrated into the user-friendly open-source Aparecium software. Both image analysis methods were suitable for measuring fluorescence ligand saturation binding and kinetics as well as for screening binding affinities of unlabelled ligands.
Brauer and partition diagram models for phylogenetic trees and forests
Authors: Francis Andrew , Jarvis Peter D.
Published: June 2022

We introduce a correspondence between phylogenetic trees and Brauer diagrams, inspired by links between binary trees and matchings described by Diaconis and Holmes (1998Proc. Natl Acad. Sci. USA95, 14 600–14 602. (doi:10.1073/pnas.95.25.14600)). This correspondence gives rise to a range of semigroup structures on the set of phylogenetic trees, and opens the prospect of many applications. We furthermore extend the Diaconis–Holmes correspondence from binary trees to non-binary trees and to forests, showing for instance that the set of all forests is in bijection with the set of partitions of finite sets.
The roles of growth regulation and appendage patterning genes in the morphogenesis of treehopper pronota
Authors: Kudla Anna M. , Miranda Ximena , Nijhout H. Frederik
Published: June 2022

Treehoppers of the insect family Membracidae have evolved enlarged and elaborate pronotal structures, which is hypothesized to involve co-opted expression of genes that are shared with the wings. Here, we investigate the similarity between the pronotum and wings in relation to growth. Our study reveals that the ontogenetic allometry of the pronotum is similar to that of wings in Membracidae, but not the outgroup. Using transcriptomics, we identify genes related to translation and protein synthesis, which are mutually upregulated. These genes are implicated in the eIF2, eIF4/p70S6K and mTOR pathways, and have known roles in regulating cell growth and proliferation. We find that species-specific differential growth patterning of the pronotum begins as early as the third instar, which suggests that expression of appendage patterning genes occurs long before the metamorphic molt. We propose that a network related to growth and size determination is the more likely mechanism shared with wings. However, regulators upstream of the shared genes in pronotum and wings need to be elucidated to substantiate whether co-option has occurred. Finally, we believe it will be helpful to distinguish the mechanisms leading to pronotal size from those regulating pronotal shape as we make sense of this spectacular evolutionary innovation.
Effects of environment and genotype on dispersal differ across departure, transfer and settlement in a butterfly metapopulation
Authors: DiLeo Michelle F. , Nonaka Etsuko , Husby Arild , Saastamoinen Marjo
Published: June 2022

Active dispersal is driven by extrinsic and intrinsic factors at the three stages of departure, transfer and settlement. Most empirical studies capture only one stage of this complex process, and knowledge of how much can be generalized from one stage to another remains unknown. Here we use genetic assignment tests to reconstruct dispersal across 5 years and 232 habitat patches of a Glanville fritillary butterfly (Melitaea cinxia) metapopulation. We link individual dispersal events to weather, landscape structure, size and quality of habitat patches, and individual genotype to identify the factors that influence the three stages of dispersal and post-settlement survival. We found that nearly all tested factors strongly affected departure probabilities, but that the same factors explained very little variation in realized dispersal distances. Surprisingly, we found no effect of dispersal distance on post-settlement survival. Rather, survival was influenced by weather conditions, quality of the natal habitat patch, and a strong interaction between genotype and occupancy status of the settled habitat patch, with more mobile genotypes having higher survival as colonists rather than as immigrants. Our work highlights the multi-causality of dispersal and that some dispersal costs can only be understood by considering extrinsic and intrinsic factors and their interaction across the entire dispersal process.
Hilltopping influences spatial dynamics in a patchy population of tiger moths
Authors: Pepi Adam , Grof-Tisza Patrick , Holyoak Marcel , Karban Richard
Published: June 2022

Dispersal is a key driver of spatial population dynamics. Dispersal behaviour may be shaped by many factors, such as mate-finding, the spatial distribution of resources, or wind and currents, yet most models of spatial dynamics assume random dispersal. We examined the spatial dynamics of a day-flying moth species (Arctia virginalis) that forms mating aggregations on hilltops (hilltopping) based on long-term adult and larval population censuses. Using time-series models, we compared spatial population dynamics resulting from empirically founded hilltop-based connectivity indices and modelled the interactive effects of temperature, precipitation and density dependence. Model comparisons supported hilltop-based connectivity metrics including hilltop elevation over random connectivity, suggesting an effect of hilltopping behaviour on dynamics. We also found strong interactive effects of temperature and precipitation on dynamics. Simulations based on fitted time-series models showed lower patch occupancy and regional synchrony, and higher colonization and extinction rates when hilltopping was included, with potential implications for the probability of persistence of the patch network. Overall, our results show the potential for dispersal behaviour to have important effects on spatial population dynamics and persistence, and we advocate the inclusion of such non-random dispersal in metapopulation models.
Changes in mean body size in an expanding population of a threatened species
Authors: Hays Graeme C. , Taxonera Albert , Renom Berta , Fairweather Kirsten , Lopes Anice , Cozens Jacquie , Laloë Jacques-Olivier
Published: June 2022

With some taxa, a reduction in the mean size of individuals may reflect over-harvesting and/or trophy hunting. However, we show that in sea turtles, a reduction in the mean size of breeding individuals may be part of the good news story of an expanding population. We describe a 70-fold increase in annual nest numbers on the island of Sal (Cape Verde, North Atlantic) between 2008 and 2020 (from 506 to 35 507 nests), making this now one of the largest loggerhead (
Caretta caretta
) nesting aggregations in the world. We use 20 128 measurements of the size of nesting turtles to show that their mean annual size has decreased by about 2.4 cm, from 83.2 to 80.8 cm. This decrease in the mean size of nesting turtles was not caused by the removal of larger turtles, for example by selective harvesting. Rather we develop a theoretical model to show than this decrease in mean size can be explained by an influx of first-time nesters, combined with a decrease in the size of those first-time nesters over time. A reduction in mean size of nesting turtles has been reported across the Atlantic, Pacific and Indian Oceans, and may be a common feature of population recoveries in sea turtles.
Methylophaga pinxianii sp. nov., isolated from the Mariana Trench
Authors: Wei Ting-Ting , Zhang Ru-Yi , Quan Zhe-Xue
Published: June 2022

Two strains, TMB456T and TMB1265, were isolated from different locations in the Mariana Trench. Analysis of the 16S rRNA gene and genomic rRNA sequences indicated that they were from the same novel species and were affiliated with the genus

Methylophaga

of the class

Gammaproteobacteria

. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the most closely related validly published species were

Methylophaga muralis

Kr3T (98.1 % similarity) and

Methylophaga nitratireducenticrescens

JAM1T (97.3 % similarity). Digital DNA–DNA hybridization values of TMB456T with

M. muralis

Kr3T and

M. nitratireducenticrescens

JAM1T were <25 %. The average nucleotide identity value between strain TMB456T and

M. muralis

Kr3T was 80.9 %. The genomic DNA G+C contents of strains TMB456T and TMB1265 were both 44.9 mol %. Strains TMB456T and TMB1265 could grow at 4–37 °C (optimum at 20–28 °C), at pH 3–10 (optimum at pH 7–9) and in the presence of 0–10 % (w/v) NaCl (optimum at 0–1 %). Cells of strains TMB456T and TMB1265 were Gram-negative rods (0.3–0.6 µm×0.7–1.3 µm). Chemotaxonomic analysis showed that ubiquinone 8 was the sole quinone produced by strain TMB456T and that the major cellular fatty acids were iso-C16 : 0, summed feature 3 (C16 : 1
 ω7c and/or C16 : 1
 ω6c) and summed feature 8 (C18 : 1
 ω7c and/or C18 : 1
 ω6c). The polar lipid profile of this strain included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphoglycolipids and two unidentified polar lipids. Based on the phenotypic, chemotaxonomic and molecular features, strains TMB456T and TMB1265 belong to a novel species within the genus

Methylophaga

, for which the name Methylophaga pinxianii sp. nov. is proposed. The type strain is TMB456T (=KCTC 82622T= MCCC 1K05898T).
Origins and Evolution of Seasonal Human Coronaviruses
Authors: Otieno JR , Cherry JL , Spiro DJ , Nelson MI , Trovao NS
Published: June 2022

Four seasonal human coronaviruses (sHCoVs) are endemic globally (229E, NL63, OC43, and HKU1), accounting for 5-30% of human respiratory infections. However, the epidemiology and evolution of these CoVs remain understudied due to their association with mild symptomatology. Using a multigene and complete genomes analysis approach, we find the evolutionary histories of sHCoVs to be more complex than previously recognized, owing to frequent recombination of CoVs, including within and between sHCoVs. Within sHCoV recombination rate was highest for 229E and OC43, and within genus highest for betaCoVs, whereas substitutions per recombination event inversely highest in NL63 and HKU1, and the alphaCoVs. Depending on the gene studied, OC43 may have ungulate, canine, or rabbit CoV ancestors, while 229E may have origins in a bat, camel or an unsampled intermediate host. HKU1 had the earliest most recent common ancestor (MRCA: 1809-1899), comprised two genetically divergent genotypes (A and B) possibly representing two independent transmission events from murine CoVs, and genotype B was genetically more diverse than all the other sHCoVs. Finally, we found shared amino acid substitutions in multiple proteins along the non-human to sHCoV host-jump branches. The complex evolution of CoVs and their frequent host switches could benefit from continued surveillance of CoVs across non-human hosts.
The TonB dependent uptake of pyrroloquinoline-quinone (PQQ) and secretion of gluconate by Escherichia coli K-12
Authors: Hantke Klaus , Friz Simon
Published: June 2022

Glucose is taken up by Escherichia coli through the phosphotransferase system (PTS) as the preferred carbon source. PTS mutants grow with glucose as a carbon source only in the presence of pyrroloquinoline quinone (PQQ), which is needed as a redox cofactor for the glucose dehydrogenase Gcd. The membrane-anchored Gcd enzyme oxidizes glucose to gluconolactone in the periplasm. For this reaction to occur, external supply of PQQ is required as E. coli is unable to produce PQQ de novo. Growth experiments show that PqqU (YncD) is the TonB-ExbBD dependent transporter for PQQ through the outer membrane. PQQ protected the cells from the PqqU dependent phage IsaakIselin (Bas10) by competition for the receptor protein. As a high affinity uptake system PqqU allows E. coli to activate Gcd even at surrounding PQQ concentrations of about 1 nmol/l. At about 30 fold higher PQQ concentrations the activation of Gcd gets PqqU independent. Due to its small size Pqq may also pass the outer membrane through porins. The PQQ dependent production of gluconate has been demonstrated in many plant growth promoting bacteria that solubilise phosphate minerals in the soil by secreting this acid. Under Pi limiting conditions also E. coli induces the glucose dehydrogenase and secretes gluconate, even in absence of PTS, that is, even when the bacterium is unable to grow on glucose without PQQ.
Instagram for student learning and library promotions: a quantitative study using the 5E Instructional Model
Authors: Lam Apple Hiu Ching , Ho Kevin K.W. , Chiu Dickson K.W.
Published: June 2022

Purpose

Libraries worldwide, including Hong Kong, increasingly use social media tools to introduce and promote their services and resources to users. Instagram, in particular, is used to target younger users. This study investigates the effectiveness of Instagram in promoting library services and university students' perceptions of the value of Instagram as a learning support tool.

Design/methodology/approach

A major academic library in Hong Kong was chosen for this study. Library users' habits, perceptions, preferences, and views on Instagram's effectiveness as a learning support tool were compared in two age groups. The data were collected using a survey based on the 5E Instructional Model.

Findings

Despite the significantly higher frequency of Instagram use by younger students, the results showed that Instagram was probably an ineffective promotion platform for either age group because of low user engagement, relatively neutral perception of Instagram as a learning support tool, and notably low user acceptance of Instagram as a promotional tool.

Originality/value

Studies of student perspectives on various social media tools have increased; however, few have explored the use of Instagram, especially in Hong Kong or Asia. This study provides researchers and librarians with practical insights into current Instagram users' engagement, perceptions, and preferences and their view of its effectiveness as a learning support tool. The study also provides suggestions for improving the current situation.
The influence of digital entrepreneurship and entrepreneurial orientation on intention of family businesses to adopt artificial intelligence: examining the mediating role of business innovativeness
Authors: Upadhyay Nitin , Upadhyay Shalini , Al-Debei Mutaz M. , Baabdullah Abdullah M. , Dwivedi Yogesh K.
Published: June 2022

Purpose

This study aims to investigate the adoption intention of artificial intelligence (AI) in family businesses through the perspectives of digital entrepreneurship and entrepreneurship orientation.

Design/methodology/approach

The study examines contributing factors explaining the adoption intention of AI in the context of family businesses. The developed research model is examined and validated using structural equation modelling based on 631 respondents' data. Purposeful sampling is used to collect the respondents' data.

Findings

The proposed model included two endogenous (i.e. business innovativeness and adoption intention) and six exogenous variables (i.e. affordances, culture and flexible design, entrepreneurial orientation, generativity, openness and technology orientation) through ten direct paths and three indirect paths. The results depicted the significant influence of all the exogenous variables on the endogenous variable reflecting support of all the hypotheses. The business innovativeness partially mediates the relationships of culture and flexible design, entrepreneurial orientation and technology orientation with adoption intention. Further, the results demonstrated a model variance of 24.6% for business innovativeness and 64.2% for adoption intention of artificial intelligence in the family business.

Research limitations/implications

The study contributes to theoretical developments in entrepreneurship and family business research and AI's theoretical progress, especially to digital entrepreneurship.

Originality/value

Theoretically, it contributes to the literature of entrepreneurship, particularly digital entrepreneurship. Additionally, the research model adds to the role of entrepreneurial orientation and digital entrepreneurship in the emerging family entrepreneurship literature. Considering the scarcity of research in this field, the empirically validated model explaining critical antecedents of AI adoption intention in the family business is a foundation for discussion, critique and future research.
An exploration of applicability of social constructivism approach in distance learning amid the COVID-19 pandemic; the case study of Hail University (UOH)
Authors: Abdullah Alkhabra Saleh
Published: June 2022

Purpose

The study aimed to explore and understand the perceptions of students, teachers and management about the distance learning and student learning at University of Hail (UOH) amid the COVID-19 pandemic, to identify whether student learning needs are being addressed in (UOH). This is facilitated through the use of interaction of distance learner with their peer groups, faculty members and assistants using different modes of interactions such as computers, internets such as chats and yahoo groups and mobile phones. These features of UOH approach toward learning are among the constructivist approach.

Design/methodology/approach

A qualitative research methodology was used to attain the objectives of this study. Looking into the nature, aim and objectives of the research study, semi-structured interviews were suitable and case studies, in total 11 interviews were conducted; five interviews were conducted from the students, three from the faculty members and three from the university administration. An interview guide was developed to conduct the interviews on the basis of themes such as training and development, performance management and firm performance. The data analysis suggests that UOH adopts quite a lot of main features of social constructivist approach of learning and teaching. This study finds that UOH adopts student-centered approach and provides the students opportunities to learn from real-life scenarios through case studies and projects.

Findings

This study has certain important theoretical contributions and implications for policy makers and managers; this study contributes to the distance learning education literature by exploring and understanding the perceptions of students, faculty members and management about the learning at UOH. The results of this study may be used by teachers and other instructional designers to improve materials for emergency distance learning.

Research limitations/implications

This study contains certain limitations. One key limitation is the limited number of interviews originating from lack of time and problems in accessing the university. Hence, more interviews would have provided a more detailed picture of the learning at UOH. Another limitation is the context based nature of this study, not allowing generalization of the results. Nevertheless, generalizations were not amongst the purposes of this study and hence were never intended. Due to this limitation findings can be argued as applicable and meaningful to a certain degree as determined by other researchers and practitioners.

Originality/value

This research also focuses on the social constructivist approach to distance learning by examining and analyzing how learning at UOH appears to align with the constructivist approach's learning values.
Hybridized neural network inspired behavioural modelling of pneumatic artificial muscles for assistive robotic applications
Authors: Arora Aman , Sarkar Debadrata , Majumder Arunabha , Sen Soumen , Roy Shibendu Shekhar
Published: June 2022

Purpose

This paper aims to devise a first-of-its-kind methodology to determine the design, operating conditions and actuation strategy of pneumatic artificial muscles (PAMs) for assistive robotic applications. This requires extensive characterization, data set generation and meaningful modelling between PAM characteristics and design variables. Such a characterization should cover a wide range of design and operation parameters. This is a stepping stone towards generating a design guide for this highly popular compliant actuator, just like any conventional element of a mechanism.

Design/methodology/approach

Characterization of a large pool of custom fabricated PAMs of varying designs is performed to determine their static and dynamic behaviours. Metaheuristic optimizer-based artificial neural network (ANN) structures are used to determine eight different models representing PAM behaviour. The assistance of knee flexion during level walking is targeted for evaluating the applicability of the developed actuator by attaching a PAM across the joint. Accordingly, the PAM design and the actuation strategy are optimized through a tabletop emulator.

Findings

The dependence of passive length, static contraction, dynamic step response for inflation and deflation of the PAMs on their design dimensions and operating parameters is successfully modelled by the ANNs. The efficacy of these models is investigated to successfully optimize the PAM design, operation parameters and actuation strategy for using a PAM in assisting knee flexion in human gait.

Originality/value

Characterization of static and the dynamic behaviour of a large pool of PAMs with varying designs over a wide range of operating conditions is the novel feature in this article. A lucid customizable fabrication technique is discussed to obtain a wide variety of PAM designs. Metaheuristic-based ANNs are used for tackling high non-linearity in data while modelling the PAM behaviour. An innovative tabletop emulator is used for investigating the utility of the models in the possible application of PAMs in assistive robotics.
Non-redundant inertial parameters determination for dynamic identification of branched articulated robots
Authors: Tan Chao , Zhao Huan , Ding Han
Published: June 2022

Purpose

Branched articulated robots (BARs) are highly non-linear systems; accurate dynamic identification is critical for model-based control in high-speed and heavy-load applications. However, due to some dynamic parameters being redundant, dynamic models are singular, which increases the calculation amount and reduces the robustness of identification. This paper aims to propose a novel methodology for the dynamic analysis and redundant parameters elimination of BARs.

Design/methodology/approach

At first, the motion of a rigid body is divided into constraint-dependent and constraint-independent. The redundancy of inertial parameters is analyzed from physical constraints. Then, the redundant parameters are eliminated by mapping posterior links to their antecedents, which can be applied for re-deriving the Newton–Euler formulas. Finally, through parameter transformation, the presented dynamic model is non-singular and available for identification directly.

Findings

New formulas for redundant parameters elimination are explicit and computationally efficient. This unifies the redundant parameters elimination of prismatic and revolute joints for BARs, and it is also applicable to other types of joints containing constraints. The proposed approach is conducive to facilitating the modelling phase during the robot identification. Simulation studies are conducted to illustrate the effectiveness of the proposed redundant parameters elimination and non-singular dynamic model determination. Experimental studies are carried out to verify the result of the identification algorithm.

Originality/value

This work proposes to determine and directly identify the non-redundant dynamic model of robots, which can help to reduce the procedure of obtaining the reversible regression matrix for identification.
Sponsoring many or few sports properties? Moderated mediation effect of perceived sponsor ubiquity depending on sponsor–property fit
Authors: Kang Taeahn , Matsuoka Hirotaka
Published: June 2022

Purpose

This study aims to examine the effect of the perceived sponsor ubiquity on sponsor favorability via perceived sponsor sincerity and the moderating effect of perceived sponsor–property fit.

Design/methodology/approach

Two studies via a questionnaire survey of spectators attending a Japanese professional basketball game were conducted, and Hayes’ PROCESS macro was used for data analyses. Study 1 (n = 134) assessed how perceived sponsor ubiquity affected sponsor favorability via perceived sponsor sincerity. Study 2 (n = 206) examined a moderated mediation model incorporating a perceived sponsor–property fit.

Findings

In Studies 1 and 2, spectators perceiving a higher degree of sponsor ubiquity reported a lower degree of sponsor sincerity compared with those perceiving a lower degree of sponsor ubiquity and less favorability toward sponsors. In Study 2, the less positive effect of highly perceived ubiquity was weakened when spectators perceived a higher degree of sponsor–property fit.

Practical implications

The findings provided sponsors with insights into effectively communicating perceived ubiquity and perceived sponsor–property fit. Hence, sponsors must be careful about their ubiquitous sponsorships, as their engagement in each property can be perceived as less distinctive among consumers.

Originality/value

To the best of the authors’ knowledge, this study is the first to highlight the mediating mechanism of perceived insincerity between perceived ubiquity and favorability toward sponsors. Furthermore, evidence that fit acted as a moderator on perceived ubiquity–outcome relationships extended previous studies mainly treating fit as a direct antecedent of sponsor response.
Dynamic and ambidextrous: international expansion of digital economy ventures from an emerging market
Authors: Buyukbalci Pinar , Dulger Meral
Published: June 2022

Purpose

This study aims to explore the internationalization trajectory of emerging country digital economy ventures by specifically concentrating on how ambidexterity facilitates international market expansion. Further, this paper examines how these ventures develop dynamic capabilities by using their ambidextrous skills in the entrepreneurial ecosystem (EE).

Design/methodology/approach

This study adopts a multiple-case research design where data were gathered from five digital economy ventures in Turkey, serving an international array of customers.

Findings

The analyses reveal that, to a large extent, internationalization is enabled by the extensive use of ambidextrous skills in the ecosystem domain. We found evidence for practicing exploration and exploitation while interacting with several ecosystem pillars grouped as founder-related, firm-related and business context-related factors. These interactions portray how ventures sense, seize and transform resources to support their international expansion.

Originality/value

This study extends the current literature on internationalization by discussing the role of ambidexterity as a dynamic capability. The findings also demonstrate the EE as a construct to explain international entrepreneurial activity. Further, the study extends the existing literature by considering the calls for research on dynamic capabilities of international new ventures (INVs). Finally, the findings point to several implications both for practitioners and policymakers.
Audit report construction: public sector organisation perspectives within a non-financial information context
Authors: Hecimovic Angela , Martinov-Bennie Nonna
Published: June 2022

Purpose

This study aims to explore the challenges in the construction of the audit report by a public sector organisation within a non-financial information (NFI) audit context.

Design/methodology/approach

This field study primarily uses data collected from semi-structured interviews, in addition to internal and external documents. The data are framed around the generic key audit report elements including audience, scope and criteria, and draw upon insights from Power (1999, 2003a, b) into NFI assurance and Fiske's (1990) insights into communication to draw inferences on the communicative value of the audit report under study.

Findings

The findings provide insights into the challenges in determining the appropriate stakeholder audience, objective, content and format of audit reports in a complex non-financial subject matter context. Despite the organisation going to considerable lengths to understand their audiences' needs and audit objectives/criteria when constructing the audit report as the literature suggests, unintended consequences resulted and the communicative value of the audit report was still questionable.

Research limitations/implications

The evidence was analysed from an assuror's perspective. Future research may examine in more detail the user's perceptions on the communicative value of the NFI financial audit report.

Practical implications

The paper's insights into one organisations' challenge in developing appropriate reporting practice(s) within a “new” NFI context have practical implications for the development of emerging assurance practices of other NFI both in public and private sector.

Originality/value

This paper is one of very few studies to use in-action field study approach to comprehensively examine how audit reporting practice develops in a complex non-financial subject matter context within a public sector context.
Vehicle-type strategies for manufacturer's car sharing
Authors: Liu Zhenfeng , Wang Yujie , Feng Jian
Published: June 2022

Purpose

This paper aims to study vehicle-type strategies for the manufacturer's car sharing by accounting for consumers' behavior and the subsidy.

Design/methodology/approach

The authors develop a game model, in which a monopoly manufacturer that can produce gasoline vehicles (GVs) or energy vehicles (EVs) not only sells vehicles in the sales market, but also rents them out in the sharing market by the self-built platform. The manufacturer strategically chooses which type of vehicles based on consumers' behavior and whether the government provides the EVs’ subsidy.

Findings

When consumers' low-carbon awareness is relatively high or the marginal cost is low, the manufacturer chooses EVs. The manufacturer chooses GVs when the low-carbon awareness and the marginal cost are low. Only when the low-carbon awareness and the subsidy are not too low, the manufacturer who originally chose GVs launches EVs. When the low-carbon awareness is high, the excessive subsidy discourages the manufacturer from entering the sharing market. If the government provides the subsidy, the manufacturer launches high-end EVs. Otherwise, the manufacturer launches low-end EVs. Moreover, the subsidy increases consumer surplus and social welfare since the high subsidy makes EVs’ sharing market demand be negative.

Originality/value

This study enriches the literature on vehicle-type strategies for the manufacturer's car sharing, owns a practical significance to guide the manufacturer's operation management in the car sharing market and provides advice on whether the government should provide EVs’ subsidy.
Commentary on “Research priorities relating to communication and swallowing for individuals with learning disabilities across the lifespan”
Authors: Backhouse Anna , Howells Sophie
Published: June 2022

Purpose

The purpose of this paper is to provide a commentary on the article by Chadd et al. The commentary sets out the key principles of good support and considers how the Royal College of Speech and Language Therapists research priorities impact on the practice of a team of Speech and Language Therapists who support people with learning disabilities, including autistic people and those with complex needs who display behaviour described as challenging. The commentary considers how the research priorities fit within current policies and frameworks and reflects on areas that could be considered further.

Design/methodology/approach

This commentary provides a narrative account of the reflections of a team of Speech and Language Therapists on the impact that the research priorities have had on their work.

Findings

The Speech and Language Therapy (SLT) team are all keen to be involved in research but identify barriers to this relating to time within their current roles and challenges in meaningfully involving people they support. The research priorities have provided a broad framework for them to use to consider areas for research, and the focus on measuring outcomes is welcome. The research priorities largely fit within the frameworks that support current social care practice; however, they are not written in a way that is accessible for most people with a learning disability, and some do not fully reflect the social model of disability. The wider involvement of people with lived experience may have led to different research priorities identified.

Originality/value

The commentary provides an account of the impact that the research priorities have had on a team of Speech and Language Therapists working within a social care setting. It encourages readers to consider the wider context for people with learning disabilities and the role SLT plays within the social model of support for improving quality of life.
Coronavirus disease 2019 and pityriasis rosea: A review of the immunological connection
Authors: Borgia Francesco , Li Pomi Federica , Alessandrello Clara , Vaccaro Mario , Pioggia Giovanni , Gangemi Sebastiano
Published: June 2022

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is characterized by the activation of a cytokine storm derived from an excess release of cytokine (interleukin [IL]‐6, interferon [IFN] I, C‐X‐C motif chemokine ligand [CXCL]10, tumor necrosis factor [TNF]‐α, macrophage inflammatory protein [MIP]1) due to an uncontrolled immune activation. There has been a fivefold increase in the number of cases of pityriasis rosea during the SARS‐CoV‐2 pandemic. Using the keywords “pityriasis” and “COVID‐19”, we carried out a PubMed search, including all articles in the English language published until November 2021. We aimed to investigate the possible connection between SARS‐CoV‐2 and pityriasis rosea (PR). Pityriasis could be considered an immunological disease due to the involvement of cytokines and chemokines. Our analysis yielded 65 articles of which 53 were not considered; the others (n = 12) concerning the association between PR and COVID‐19 were included in our study. We suggest two mechanisms underlying the involvement of the skin in viral infections: (i) viruses directly affecting the skin and/or inducing host immune response thus causing cutaneous manifestations; and (ii) viruses as a possible inducer of the reactivation of another virus. The first mechanism is probably related to a release of pro‐inflammatory cytokine and infection‐related biomarkers; in the second, several pathways could be involved in the reactivation of other latent viruses (human herpesviruses 6 and 7), such as a cytokine–cytokine receptor interaction, the Janus kinase–signal transducer and activator of transcription signaling pathway, and the IL‐17 signaling pathway. We thus believe that a cytokine storm could be directly or indirectly responsible for a cutaneous manifestation. More investigations are needed to find specific pathways involved and thus confirm our speculations.
Stability evaluation of gardenia yellow pigment in the presence of different antioxidants or microencapsulating agents
Authors: Wu Jun , Pu Cui , Zhang Yingjia , Wang Xiaona , Wang Maoxia , Shao Heyi , Yin Caiping , Zhang Yinglao
Published: June 2022

The chemical instability of gardenia yellow pigment (GYP) limits its utilization in the food industry. In this study, the effects of different antioxidants (0.2% of tea polyphenols, sodium phytate, potassium citrate, and ascorbic acid) and microencapsulating agents (gum Arabic, maltodextrin, inulin, and gum Arabic/maltodextrin) on the degradation of GYP under different conditions (heat, light, and ferric iron) were evaluated. Then, the characteristic properties of microcapsules coated with gum Arabic/maltodextrin, gum Arabic/maltodextrin/tea polyphenols, maltodextrin, and maltodextrin/tea polyphenols were investigated. Furthermore, food models were simulated to evaluate the GYP stability of the microcapsules. The results showed that tea polyphenols, maltodextrin, and gum Arabic/maltodextrin significantly improved the GYP stability. Moreover, the presence of GYP in microcapsules was confirmed by nuclear magnetic resonance and Fourier transform infrared spectroscopy. In addition, GYP‐MD/TP possessed high thermal stability under different cooking methods.

Practical Application

Gardenia yellow pigment (GYP) is easily degraded under light and high‐temperature conditions, which limits its applications in the food industry. This study will provide effective clues for expanding the practical applications of GYP in the natural pigment industry.