bluuebunny/crossref_metadata_2025 huggingface dataset:
Normothermic Machine Perfusion Systems: Where Do We Go From Here?
Authors: López-Martínez Sara , Simón Carlos , Santamaria Xavier
Published: April 2023

Normothermic machine perfusion (NMP) aims to preserve organs ex vivo by simulating physiological conditions such as body temperature. Recent advancements in NMP system design have prompted the development of clinically effective devices for liver, heart, lung, and kidney transplantation that preserve organs for several hours/up to 1 d. In preclinical studies, adjustments to circuit structure, perfusate composition, and automatic supervision have extended perfusion times up to 1 wk of preservation. Emerging NMP platforms for ex vivo preservation of the pancreas, intestine, uterus, ovary, and vascularized composite allografts represent exciting prospects. Thus, NMP may become a valuable tool in transplantation and provide significant advantages to biomedical research. This review recaps recent NMP research, including discussions of devices in clinical trials, innovative preclinical systems for extended preservation, and platforms developed for other organs. We will also discuss NMP strategies using a global approach while focusing on technical specifications and preservation times.
Behavioral and Brain Correlates of Emotional Distress in Older Adults During COVID-19 Quarantine
Authors: Benari Ori , Ravona Springer Ramit , Almog Ganit , Yore Iscka , Zadok Maya , Lin Hung-Mo , Ouyang Yuxia , Sano Mary , Bendlin Barbara B. , Livny Abigail , Heymann Anthony , Schnaider Beeri Michal
Published: April 2023

COVID-19 led to unprecedented lockdowns and changes in older adults’ lives, especially those with type 2 diabetes who have high risk of complications and mortality. We investigated the associations of cognitive and motor function and gray matter volumes (GMVs) with COVID-19 lockdown-related emotional distress of type 2 diabetes older adults, participating in the Israel Diabetes and Cognitive Decline Study. We administered a questionnaire to obtain information about anxiety, depression, general well-being, and optimism during a mandated lockdown. Lower grip strength before lockdown was associated with increased sadness, anxiety, and less optimism. Slower gait speed was associated with greater sadness. Lower GMV was related to greater anxiety during the lockdown when compared with anxiety levels before the COVID-19 outbreak. Yet, global cognition was not associated with any emotional distress measure. These results support the role of good motor function on emotional well-being during acute stress and GMV as a potential underlying mechanism.
Yield of Staging Laparoscopy for Pancreatic Cancer in the Modern Era: Analysis of Over 1000 Consecutive Patients
Authors: Gudmundsdottir Hallbera , Yonkus Jennifer A , Alva-Ruiz Roberto , Kendrick Michael L , Smoot Rory L , Warner Susanne G , Starlinger Patrick , Thiels Cornelius A , Nagorney David M , Cleary Sean P , Grotz Travis E , Truty Mark J
Published: April 2023

Background:

Accurate staging prior to resection of pancreatic ductal adenocarcinoma (PDAC) is imperative to avoid unnecessary operative morbidity and oncologic futility in patients with occult intraabdominal distant metastases. We aimed to determine the diagnostic yield of staging laparoscopy (SL) and identify factors associated with increased risk of positive laparoscopy (PL) in the modern era.

Study Design:

Patients with radiographically localized PDAC who underwent SL 2017-2021 were retrospectively reviewed. The yield of SL was defined as the proportion of patients with PL, including gross metastases and/or positive peritoneal cytology. Factors associated with PL were assessed using univariate analysis and multivariable logistic regression.

Results:

Of 1004 patients who underwent SL, 180 (18%) had PL due to gross metastases (n=140) and/or positive cytology (n=96). Patients who had neoadjuvant chemotherapy prior to laparoscopy had lower rates of PL (14% versus 22%, p=0.002). When the analysis was restricted to chemo-naive patients who had concurrent peritoneal lavage performed, 95 of 419 patients (23%) had PL. In multivariable analysis, PL was associated with younger (<60) age, indeterminate extrapancreatic lesions on preoperative imaging, body/tail tumor location, larger tumor size, and elevated serum CA 19-9 (all p<0.05). Among patients with no indeterminate extrapancreatic lesions on preoperative imaging, the rate of PL ranged from 1.6% in patients with no risk factors to 42% in young patients with large body/tail tumors and elevated serum CA 19-9.

Conclusion:

The rate of PL in patients with PDAC remains high in the modern era. SL with peritoneal lavage should be considered for the majority of patients prior to resection, specifically those with high-risk features, and ideally prior to neoadjuvant chemotherapy.
Longitudinal study of humoral immunity against SARS-CoV-2 of health professionals in Brazil: the impact of booster dose and reinfection on antibody dynamics
Authors: Franco-Luiz Ana Paula Moreira , Fernandes Nubia Monteiro Gonçalves Soares , de Souza Silva Thais Bárbara , de Oliveira Santos Bernardes Wilma Patrícia , Westin Mateus Rodrigues , Santos Thais Garcia , da Rocha Fernandes Gabriel , Simões Taynãna César , e Silva Eduardo Fernandes , Gava Sandra Grossi , Alves Breno Magalhães , de Carvalho Melo Mariana , da Silva-Pereira Rosiane A. , Alves Pedro Augusto , Fonseca Cristina Toscano
Published: April 2023

The pandemic caused by SARS-CoV-2 has had a major impact on health systems. Vaccines have been shown to be effective in improving the clinical outcome of COVID-19, but they are not able to fully prevent infection and reinfection, especially that caused by new variants. Here, we tracked for 450 days the humoral immune response and reinfection in 52 healthcare workers from Brazil. Infection and reinfection were confirmed by RT-qPCR, while IgM and IgG antibody levels were monitored by rapid test. Of the 52 participants, 19 (36%) got reinfected during the follow-up period, all presenting mild symptoms. For all participants, IgM levels dropped sharply, with over 47% of them becoming seronegative by the 60th day. For IgG, 90% of the participants became seropositive within the first 30 days of follow-up. IgG antibodies also dropped after this period reaching the lowest level on day 270 (68.5±72.3, p<0.0001). Booster dose and reinfection increased the levels of both antibodies, with the interaction between them resulting in an increase in IgG levels of 130.3 units. Overall, our data indicate that acquired humoral immunity declines over time and suggests that IgM and IgG antibody levels are not associated with the prevention of reinfection.

Importance

This prospective observational study monitored the kinetics of humoral response and the occurrence of reinfection in a population of healthcare workers (HCW) who got COVID-19 over a period of 450 days. During the study period, HCW was a prioritized in COVID-19 vaccination campaign, several SARS-CoV-2 variants of concern circulated in the country, and nineteen participants of the study got reinfected. So, we were able to investigate the duration of humoral response against COVID-19, the impact of vaccination boost and reinfection in the production of anti-SARS-CoV-2 antibodies, and the associating of this antibodies with protection against reinfection. These information are important to support health managers in defining COVID19 surveillance and control actions.
euka: Robust detection of eukaryotic taxa from modern and ancient environmental DNA using pangenomic reference graphs
Authors: Vogel Nicola Alexandra , Rubin Joshua Daniel , Swartz Mikkel , Vlieghe Juliette , Sackett Peter Wad , Pedersen Anders Gorm , Pedersen Mikkel Winther , Renaud Gabriel
Published: April 2023

1. Ancient environmental DNA (eDNA) is a crucial source of in-formation for past environmental reconstruction. However, the com-putational analysis of ancient eDNA involves not only the inherited challenges of ancient DNA (aDNA) but also the typical difficulties of eDNA samples, such as taxonomic identification and abundance esti-mation of identified taxonomic groups. Current methods for ancient eDNA fall into those that only perform mapping followed by taxo-nomic identification and those that purport to do abundance estima-tion. The former leaves abundance estimates to users, while methods for the latter are not designed for large metagenomic datasets and are often imprecise and challenging to use.

2. Here, we introduce euka, a tool designed for rapid and accurate characterisation of ancient eDNA samples. We use a taxonomy-based pangenome graph of reference genomes for robustly assigning DNA sequences and use a maximum-likelihood framework for abundance estimation. At the present time, our database is restricted to mito-chondrial genomes of tetrapods and arthropods but can be expanded in future versions.

3. We find euka to outperform current taxonomic profiling tools as well as their abundance estimates. Crucially, we show that regardless of the filtering threshold set by existing methods, euka demonstrates higher accuracy. Furthermore, our approach is robust to sparse data, which is idiosyncratic of ancient eDNA, detecting a taxon with an average of fifty reads aligning. We also show that euka is consistent with competing tools on empirical samples and about ten times faster than current quantification tools.

4. euka’s features are fine-tuned to deal with the challenges of ancient eDNA, making it a simple-to-use, all-in-one tool. It is available on GitHub:https://github.com/grenaud/vgan. euka enables re-searchers to quickly assess and characterise their sample, thus allowing it to be used as a routine screening tool for ancient eDNA.
Integration of serial self-testing for COVID-19 as part of contact tracing in the Brazilian public health system: A pragmatic trial protocol
Authors: Green Rebecca K. , Manchola Camilo , Gerth-Guyette Emily , Silva Michelle Oliveira , Stephanie Raissa , Santos Soares Tainá dos , Gottin Luiza Bastos , Coelho Milena , Green Kimberly E. , Costa Alexandre Dias Tavares , Pereira Dhélio Batista
Published: April 2023

Background

The coronavirus disease (COVID-19) pandemic has led to an unprecedented public health crisis. Insufficient testing continues to limit the effectiveness of the global response to the COVID-19 pandemic. Molecular testing methods such as reverse transcriptase polymerase chain reaction (RT-PCR) continue to be highly centralized and are a sub-optimal option for population surveillance. Rapid antigen tests (Ag-RDTs) offer multiple benefits including low costs, high flexibility to conduct tests in a wide variety of settings, and faster return of results. Recently, self-test Ag-RDTs (STs) have gained approval in several markets and offer the possibility to expand testing, reaching at-risk populations. While STs have the potential to assist the COVID-19 response, test result integrity, reporting, and appropriate linkage to care continue to hinder the widespread implementation of self-testing programs.

Methods

This protocol presents a mixed-methods pragmatic trial (ISRCTN91602092) to better understand the feasibility of self-testing as part of a contact tracing strategy within the Brazilian public health system. Approximately 604 close contacts of 150 index cases testing positive for COVID-19 will be enrolled. Close contacts will be randomized to either serial (daily) self-testing over a 10-day follow-up period or a more traditional approach to contact tracing with a professional Ag-RDT at one time point post-exposure. Usability workshops and focus group discussions will also be conducted.

Discussion

This study protocol presents a comprehensive plan to assess the effectiveness, operational feasibility, and stakeholder preferences of a serial self-testing strategy for contact tracing within the Brazilian public health system. Our results will contribute to better understanding of the feasibility of a self-testing strategy within the public sector. Potential risks and limitations are discussed. Our findings will have important implications as governments continue working to mitigate the impact of COVID-19, particularly in the context of where to direct limited resources for testing and healthcare infrastructure.
The value of inspiratory muscle training on post-stroke sarcopenia and its effect on rehabilitation outcomes: A randomized controlled trial
Authors: Zhao Qianping , Shao Chenlan , Wang Yongzheng , Zhao Weiwei , Wang Liang , Zhou Wei , Mo Yuxing
Published: April 2023

Withdrawal statement: The authors have withdrawn their manuscript owing to that this manuscript still needs to be revised. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.
Predictors of acute ischemic cerebral lesions in immune-mediated thrombotic thrombocytopenic purpura and hemolytic uremic syndrome
Authors: Neuman Lisa , Joseph Adrien , Bouzid Raïda , Lescroart Mickael , Mariotte Eric , Ederhy Stéphane , Tuffet Sophie , Baudel Jean-Luc , Benhamou Ygal , Galicier Lionel , Grangé Steven , Provôt François , Neel Antoine , Pène Frédéric , Delmas Yahsou , Presne Claire , Poullin Pascale , Wynckel Alain , Perez Pierre , Barbet Christelle , Halimi Jean-Michel , Chatelet Valérie , Rebibou Jean-Michel , Ojeda-Uribe Mario , Vigneau Cécile , Mesnard Laurent , Veyradier Agnès , Azoulay Elie , Coppo Paul , Chabriat Hugues
Published: April 2023

Background

The immune form of thrombotic thrombocytopenic purpura (iTTP) and the hemolytic and uremic syndrome (HUS) are two major forms of thrombotic microangiopathy (TMA). Their treatment has been recently greatly improved. In this new era, both the prevalence and predictors of cerebral lesions occurring during the acute phase of these severe conditions remain poorly known.

Aim

The prevalence and predictors of cerebral lesions appearing during the acute phase of iTTP and shigatoxin-producingEscherichia coli-HUS or atypical HUS were evaluated in a prospective multicenter study.

Methods

Univariate analysis was performed to report the main differences between patients with iTTP and those with HUS or between patients with acute cerebral lesions and the others. Multivariable logistic regression analysis was used to identify the potential predictors of these lesions.

Results

Among 73 TMA cases (mean age 46.89 ± 15.99 years (range: 21-87 years) with iTTP (n = 57) or HUS (n= 16), one third presented with acute ischemic cerebral lesions on magnetic resonance imagery (MRI); two individuals also had hemorrhagic lesions. One in ten patients had acute ischemic lesions without any neurological symptom. The neurological manifestations did not differ between iTTP and HUS. In multivariable analysis, 3 factors predicted the occurrence of acute ischemic lesions on cerebral MRI: 1) the presence of old infarcts on cerebral MRI, 2) the level of blood pulse pressure, 3) the diagnosis of iTTP.

Conclusion

Cerebral MRI is crucial to detect both symptomatic and covert ischemic lesions at the acute phase of iTTP and HUS and helps identify patients with old infarcts, at the highest risk of neurological worsening. The diagnosis of iTTP further increases the risk of ischemic lesions but also an increased level of blood pressure that may represent a potential target to further improve the therapeutic management of these conditions.

Key points

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One third of patients with immune-mediated thrombotic thrombocytopenic purpura (iTTP) or the hemolytic uremic syndrome (HUS) present with acute ischemic cerebral lesions on magnetic resonance imagery (MRI);

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The cerebral manifestations on MRI did not differ between iTTP and HUS;

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The presence of old infarcts on cerebral MRI, the level of blood pulse pressure and a diagnosis of iTTP predict the occurrence of acute ischemic lesions on cerebral MRI.
SaLSa: a combinatory approach of semi-automatic labeling and long short-term memory to classify behavioral syllables
Authors: Sakata Shuzo
Published: April 2023

Accurately and quantitatively describing mouse behavior is an important area. Although advances in machine learning have made it possible to track their behaviors accurately, reliable classification of behavioral sequences or syllables remains a challenge. In this study, we present a novel machine learning approach, called SaLSa (a combination of semi-automatic labeling and long short-term memory-based classification), to classify behavioral syllables of mice exploring an open field. This approach consists of two major steps: first, after tracking multiple body parts, spatial and temporal features of their egocentric coordinates are extracted. A fully automated unsupervised process identifies candidates for behavioral syllables, followed by manual labeling of behavioral syllables using a graphical user interface. Second, a long short-term memory (LSTM) classifier is trained with the labeled data. We found that the classification performance was marked over 97%. It provides a performance equivalent to a state-of-the-art model while classifying some of the syllables. We applied this approach to examine how hyperactivity in a mouse model of Alzheimer’s disease (AD) develops with age. When the proportion of each behavioral syllable was compared between genotypes and sexes, we found that the characteristic hyper-locomotion of female AD mice emerges between 4 and 8 months. In contrast, age-related reduction in rearing is common regardless of genotype and sex. Overall, SaLSa enables detailed characterization of mouse behavior.

Significance Statement

Describing complex animal behavior is a challenge. Here, we developed an open-source, combinatory approach to behavioral syllable classification, called SaLSa (a combination ofsemi-automatic labeling andlongshort-term memory-based classification). In order to classify behavioral syllables, this approach combines multiple machine learning methods to label video frames semi- automatically and train a deep learning model. To demonstrate SaLSa’s versatility, we monitored the exploratory behavior of an Alzheimer’s disease mouse model and delineated their complex behaviors. We found that female Alzheimer’s mice become hyperactive in the sense that their locomotion behavior, but not other active behaviors, appear more frequently than controls and even male Alzheimer’s mice as they age. SaLSa offers a toolkit to analyze complex behaviors.
Missense variants inPLA2G6contribute to a spectrum of clinical syndromes and provide pharmacogenomic correlates
Authors: Janardhanan Meghana , Anbhazagan Padmanabhan , Viswanath Biju , Balasundaram Padmanabhan , Jain Sanjeev , Purushottam Meera
Published: April 2023

Background

Risk alleles in a gene for a genetic disorder can often cause a spectrum of syndromes. The number of copies, deleteriousness and position in the sequence could influence phenotype manifestation.

Methods

Whole exome sequencing in 310 individuals from 100 families with severe mental illness revealed 851 instances of variants in thePLA2G6gene. We assessed the population frequency and deleteriousness of the nonsynonymous variants usingin-silicoprediction methods. Molecular docking analyses with antipsychotics was performed to investigate possible pharmacogenomic implications of thePLA2G6mutations identified.

Results

We found six nonsynonymous variants predicted to be deleterious by VarSome. The frequency of non-synonymous variants was found to vary across populations. The preliminary molecular docking analysis suggests that chlorpromazine and risperidone are predicted to bind at three drug-binding sites however, risperidone has a greater binding affinity to PLA2G6. The occurrence of variants close to these drug-binding sites suggests a possible mechanism for the mediation of parkinsonian side effects on drug intake in patients harboring these variants.

Conclusion

Variants in thePLA2G6, a gene previously known to be associated with Parkinson’s disease may thus contribute to the risk of psychiatric phenotypes, as observed in these 9 individuals from 6 families with severe mental illness.
Integrating multiple single-cell multi-omics samples with Smmit
Authors: Wan Changxin , Ji Zhicheng
Published: April 2023

Multi-sample single-cell multi-omics datasets, which simultaneously measure multiple data modalities in the same cells across multiple samples, facilitate the study of gene expression, gene regulatory activities, and protein abundances on a population scale. We developed Smmit, a computational method for integrating data both across samples and modalities. Compared to existing methods, Smmit more effectively removes batch effects while preserving relevant biological information, resulting in superior integration outcomes. Additionally, Smmit is more computationally efficient and builds upon existing computational pipelines, requiring minimal effort for implementation. Smmit is an R software package that is freely available on Github:https://github.com/zji90/Smmit.
BetaBuddy: An end-to-end computer vision pipeline for the automated analysis of insulin secreting β-cells
Authors: Alsup Anne M. , Fowlds Kelli , Cho Michael , Luber Jacob M.
Published: April 2023

Insulin secretion from pancreatic β-cells is integral in maintaining the delicate equilibrium of blood glucose levels. Calcium is known to be a key regulator and triggers the release of insulin. This sub-cellular process can be monitored and tracked through live-cell imaging and subsequent cell segmentation, registration, tracking, and analysis of the calcium level in each cell. Current methods of analysis typically require the manual outlining of β-cells, involve multiple software packages, and necessitate multiple researchers - all of which tend to introduce biases. Utilizing deep learning algorithms, we have therefore created a pipeline to automatically segment and track thousands of cells, which greatly reduces the time required to gather and analyze a large number of sub-cellular images and improve accuracy. Tracking cells over a time-series image stack also allows researchers to isolate specific calcium spiking patterns and spatially identify those of interest, creating an efficient and user-friendly analysis tool. Using our automated pipeline, a previous dataset used to evaluate changes in calcium spiking activity in β-cells post-electric field stimulation was reanalyzed. Changes in spiking activity were found to be underestimated previously with manual segmentation. Moreover, the machine learning pipeline provides a powerful and rapid computational approach to examine, for example, how calcium signaling is regulated by intracellular interactions in a cluster of β-cells.
Structured memory representations develop at multiple time scales in hippocampal-cortical networks
Authors: Tambini Arielle , Miller Jacob , Ehlert Luke , Kiyonaga Anastasia , D’Esposito Mark
Published: April 2023

Influential views of systems memory consolidation posit that the hippocampus rapidly forms representations of specific events, while neocortical networks extract regularities across events, forming the basis of schemas and semantic knowledge. Neocortical extraction of schematic memory representations is thought to occur on a protracted timescale of months, especially for information that is unrelated to prior knowledge. However, this theorized evolution of memory representations across extended timescales, and differences in the temporal dynamics of consolidation across brain regions, lack reliable empirical support. To examine the temporal dynamics of memory representations, we repeatedly exposed human participants to structured information via sequences of fractals, while undergoing longitudinal fMRI for three months. Sequence-specific activation patterns emerged in the hippocampus during the first 1-2 weeks of learning, followed one week later by high-level visual cortex, and subsequently the medial prefrontal and parietal cortices. Schematic, sequence-general representations emerged in the prefrontal cortex after 3 weeks of learning, followed by the medial temporal lobe and anterior temporal cortex. Moreover, hippocampal and most neocortical representations showed sustained rather than time-limited dynamics, suggesting that representations tend to persist across learning. These results show that specific hippocampal representations emerge early, followed by both specific and schematic representations at a gradient of timescales across hippocampal-cortical networks as learning unfolds. Thus, memory representations do not exist only in specific brain regions at a given point in time, but are simultaneously present at multiple levels of abstraction across hippocampal-cortical networks.
The Effect of E-Cigarettes on the Human Heart Studied using Cardiomyocytes Generated from Induced Pluripotent Stem Cells
Authors: Bhowmik Ava T. , Zhao Shane R. , Wu Joseph C.
Published: April 2023

Although many dangerous effects of smoking e-cigarettes on lungs have come to light, limited and only qualitative efforts have been made to analyze the impact of e-cigarettes on the human heart directly. In this study, we experimentally determined e-liquid cardiotoxicity in both healthy cells and cells with long QT syndrome by treating healthy and diseased human cardiomyocytes with e-liquids with varying nicotine concentrations. These cardiomyocytes were generated from human induced pluripotent stem cells. The cardiomyocytes were divided into 5 groups, a control group and 4 test groups, each treated with e-liquid containing varying amounts of nicotine between 0% and 70%. The cells’ biological indicators such as heart rate, pulse pressure, essential protein concentration, and metabolic activity, were measured and characterized using three different functional assays: contractility, Western blot, and viability, and tracked over 4 days. The results demonstrated that acute exposure to e-liquid led to tachycardia, hypertension, decreased protein levels, and cell death. The rate of cardiotoxicity increases with higher nicotine concentrations. The basal fluid also showed non-negligible toxicity. Under identical conditions, the functionality of the diseased heart cells declined at a faster rate compared to healthy cells. Overall, this work establishes the harmful physiological effects of e-cigarettes on the human heart quantitatively.
Overactivated epithelial NF-κB disrupts lung development in human and nitrofen CDH
Authors: Dylong Florentine , Riedel Jan , Amonkar Gaurang M. , Peukert Nicole , Lieckfeldt Paula , Sturm Katinka , Höxter Benedikt , Tse Wai Hei , Miyake Yuichiro , Mayer Steffi , Keijzer Richard , Lacher Martin , Ai Xingbin , Gosemann Jan-Hendrik , Wagner Richard
Published: April 2023

Background & Objective

Abnormal lung development is the main cause of morbidity and mortality in neonates with congenital diaphragmatic hernia (CDH), a common birth defect (1:2500) of largely unknown pathobiology. Recent studies discovered that inflammatory processes, and specifically NF-κB associated pathways are enriched in human and experimental CDH. However, the molecular signaling of NF-κB in abnormal CDH lung development and its potential as a therapeutic target requires further investigation.

Methods & Results

Using sections and hypoplastic lung explant cultures from the nitrofen rat model of CDH and human fetal CDH lungs, we demonstrate that NF-κB and its downstream transcriptional targets are hyperactive during abnormal lung formation in CDH. NF-κB activity was especially elevated in the airway epithelium of nitrofen and human CDH lungs at different developmental stages. Fetal rat lung explants had impaired pseudoglandular airway branching after exposure to nitrofen, together with increased phosphorylation and transcriptional activity of NF-κB. Dexamethasone, the broad and clinically applicable anti-inflammatory NF-κB antagonist, rescued lung branching and normalized NF-κB signaling in hypoplastic lung explants. Moreover, specific NF-κB inhibition with curcumenol similarly rescuedex vivolung hypoplasia and restored NF-κB signaling. Lastly, we showed that prenatal intraperitoneal dexamethasone administration to pregnant rat dams carrying fetuses with hypoplastic lungs, significantly improves lung branching and normalizes NF-κBin vivo. Conclusions: Our results indicate that NF-κB is aberrantly activated in human and nitrofen CDH lungs. Anti-inflammatory treatment with dexamethasone and/ or specific NF-κB inhibition should be investigated further as a therapeutic avenue to target lung hypoplasia in CDH.
High-energy synchrotron-radiation-based X-ray micro-tomography enables non-destructive and micro-scale palaeohistological assessment of macro-scale fossil dinosaur bones
Authors: Imai Takuya , Hattori Soki , Uesugi Kentaro , Hoshino Masato
Published: April 2023

Palaeohistological analysis has numerous applications in understanding the palaeobiology of extinct dinosaurs. Recent developments of synchrotron-radiation-based X-ray micro-tomography (SXMT) have allowed the non-destructive assessment of palaeohistological features in fossil skeletons. Yet, the application of the technique has been limited to specimens on the millimetre to micrometre scale because its high-resolution capacity has been obtained at the expense of a small field of view and low X-ray energy. Here, SXMT analyses of dinosaur bones with widths measuring ∼3 cm under a voxel size of ∼4 µm at beamline BL28B2 at SPring-8 (Hyogo, Japan) are reported, and the advantages of virtual-palaeohistological analyses with large field of view and high X-ray energy are explored. The analyses provide virtual thin-sections visualizing palaeohistological features comparable with those obtained by traditional palaeohistology. Namely, vascular canals, secondary osteons and lines of arrested growth are visible in the tomography images, while osteocyte lacunae are unobservable due to their micrometre-scale diameter. Virtual palaeohistology at BL28B2 is advantageous in being non-destructive, allowing multiple sampling within and across skeletal elements to exhaustively test the skeletal maturity of an animal. Continued SXMT experiments at SPring-8 should facilitate the development of SXMT experimental procedures and aid in understanding the paleobiology of extinct dinosaurs.
Bullying, mental health and absenteeism: A moderated mediation approach
Authors: Léné Alexandre
Published: April 2023

Purpose

This study aims to examine the role of mental health disorders (anxiety and depression) underlying the relationship between bullying and absenteeism. Moreover, the author tested the potentially moderating role that job autonomy, supervisor and colleagues’ support may play in the relationship between bullying and mental health disorders.

Design/methodology/approach

A moderated mediation analysis was conducted with a sample of French workers, controlling for their individual characteristics and their working conditions. The sample comprised 22,661 employees. This sample is representative of the French working population.

Findings

The results showed that the positive relationship between workplace bullying and absenteeism was partially mediated by anxiety and depression. In addition, job autonomy and supervisor support appear to be moderators of bullying effects. Regarding the moderating role of colleagues support, the study’s results are more nuanced.

Originality/value

Many studies show that exposure to workplace bullying increases the risk of developing mental health problems and sickness absence. This study extends previous studies by proposing a more comprehensive understanding of how and when bullying results in absenteeism. In particular, this study identified some moderators that can mitigate the harmful effects of workplace bullying on mental health and absenteeism. This study contributes to the literature on this subject by showing that organizations can reduce the potentially negative effects of workplace bullying. Organizational resources can help make individuals capable of coping with aggression. They thus contribute to their resilience.
From Austrian theory of capital to dissent: Nicholas Kaldor, Friedrich A. Hayek and the way to disequilibrium
Authors: Telles Keanu
Published: April 2023

Purpose

In the early 1930s, Nicholas Kaldor could be classified as an Austrian economist. The author reconstructs the intertwined paths of Kaldor and Friedrich A. Hayek to disequilibrium economics through the theoretical deficiencies exposed by the Austrian theory of capital and its consequences on equilibrium analysis.

Design/methodology/approach

The author approaches the discussion using a theoretical and historical reconstruction based on published and unpublished materials.

Findings

The integration of capital theory into a business cycle theory by the Austrians and its shortcomings – e.g. criticized by Piero Sraffa and Gunnar Myrdal – called attention to the limitation of the theoretical apparatus of equilibrium analysis in dynamic contexts. This was a central element to Kaldor’s emancipation in 1934 and his subsequent conversion to John Maynard Keynes’ The General Theory of Employment, Interest, and Money (1936). In addition, it was pivotal to Hayek’s reformulation of equilibrium as a social coordination problem in “Economics and Knowledge” (1937). It also had implications for Kaldor’s mature developments, such as the construction of the post-Keynesian models of growth and distribution, the Cambridge capital controversy, and his critique of neoclassical equilibrium economics.

Originality/value

The close encounter between Kaldor and Hayek in the early 1930s, the developments during that decade and its mature consequences are unexplored in the secondary literature. The author attempts to construct a coherent historical narrative that integrates many intertwined elements and personas (e.g. the reception of Knut Wicksell in the English-speaking world; Piero Sraffa’s critique of Hayek; Gunnar Myrdal’s critique of Wicksell, Hayek, and Keynes; the Hayek-Knight-Kaldor debate; the Kaldor-Hayek debate, etc.) that were not connected until now by previous commentators.
Precursors and outcomes of satisfaction of fair trade coffee consumers
Authors: Mili Samira , Ferro-Soto Carlos
Published: April 2023

Purpose

This paper aims to identify the antecedents and postcedents of customer satisfaction, including utilitarian, social and emotional factors, in a fair trade (FT) coffee consumption context.

Design/methodology/approach

This paper is based on a broad range of 177 consumers of FT coffee in Spain, the data analysis used structural equation modeling (SEM) with SPSS/AMOS 26.0 software.

Findings

This paper supports that both customer social value and quality affect perceived value (PV). PV in turn has effects on customer satisfaction and the latter influences loyalty. Conversely, both customer emotional value and customer expectations were not confirmed as antecedents of PV.

Research limitations/implications

The consumer satisfaction analysis conducted differs substantially from those of conventionally traded coffee, as social and emotional factors were considered along with utilitarian factors.

Practical implications

Practitioners, retailers and relevant institutions should design strategies to manage efficiently channel efforts to improve the consumer satisfaction and its loyalty.

Originality/value

This paper contributes to a substantial improvement in the understanding of consumer satisfaction and its consequences, in FT coffee consumption contexts. A new integrated theoretical model on customer satisfaction has been provided, which includes social and emotional perception factors, along with cognitive perception (quality and expectations) factors.
How to evaluate company directors at state owned enterprises? A framework of virtue and competence based on the Chinese experience
Authors: Xu Xuhong , Hu Tiancheng , Guo Rui , Chen Shang , Ning Lutao
Published: April 2023

Purpose

This paper proposes a framework for director evaluation in the context of Chinese state-owned enterprises (SOEs), taking into account the influences of traditional and modern Chinese ideologies.

Design/methodology/approach

Following the Delphi method, a series of semi-structured interviews were conducted with Chinese SOE directors.

Findings

The framework used has been validated by examining seven dimensions of virtue and four dimensions of competence functions in Chinese SOEs. Effective and representative characteristics of each dimension are identified through interviews.

Originality/value

First, through this research, indicators of virtue have been materialized and those of competence have been specified in a broader range. Second, this research provides advice for training of candidate directors whose experience were in private firms before they step in as SOE directors.
Relationship between organisational culture and collective coping strategies in project teams: an exploratory quantitative study in the UAE construction industry
Authors: Badi Sulafa
Published: April 2023

Purpose

This study explores the role of organisational culture in promoting collective coping strategies in construction project teams in the United Arab Emirates (UAE). Three collective coping strategies were examined, including problem-focused, relationship-focused and emotion-focused coping strategies.

Design/methodology/approach

O'Reilly et al.’s (1991) organisational culture profile (OCP) assessed organisational culture values. Data were collected through an online questionnaire from practitioners in the United Arab Emirates (UAE) construction organisations.

Findings

The findings show a high correlation between competitiveness culture values and problem-focused team coping strategy. Relationship-focused team coping strategy was found to have a high correlation with emphasis on rewards and performance orientation values. Conversely, an emotion-focused team coping strategy correlates highly with competitiveness, supportiveness and emphasis on rewards cultural values.

Research limitations/implications

The cross-sectional design of the survey and the UAE context may present limits to the generalisability of findings.

Practical implications

Limited attempts have been made to study collective coping in construction project teams. The study paves the path for exploring emergent socio-psychological concepts in construction organisations, including the impact of organisational culture on team collective coping with adverse events.

Originality/value

Understanding the pivotal impact of culture on successful team coping provides managers with valuable insights into managing situational adversity in construction project teams.
Effect of Ti3SiC2 mass fraction on microstructure and tribological performance of laser cladded NiCr coating at high temperature
Authors: Chengwen Sun , Wei Li , Dejun Kong
Published: April 2023

Purpose

This paper aims to investigate the effect of Ti3SiC2 on the high-temperature tribological behaviors of NiCr coating, which was beneficial to improve the friction-wear performance of hot work mold.

Design/methodology/approach

NiCr-Ti3SiC2 coatings were prepared on H13 steel substrate by laser cladding. The microstructure, phases and hardness of obtained coatings were analyzed using a super-depth of field microscope, X-ray diffraction and microhardness tester, respectively, and the tribological performance of obtained coatings at 500°C was investigated using a high-temperature tester.

Findings

The results show the NiCr-Ti3SiC2 coatings are comprised of γ-Ni solid, solution, TixNiy, TiC and Ti3SiC2 phases, and the coating hardness is increased with the increase of Ti3SiC2 mass fraction, which is contributed to the fine-grain and dispersion strengthening effect by the addition of Ti3SiC2. The NiCr-Ti3SiC2 coatings present excellent friction reduction and wear resistance by the synergetic action of Ti3SiC2 lubricant and hard phase, and the wear mechanism is predominated by abrasive wear and oxidation wear.

Originality/value

Ti3SiC2 phase was used to reinforce the tribological performance of H13 steel at high temperature, and the roles of friction reduction and wear resistance were discussed.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2023-0004/
Do avatar-assisted virtual classrooms work for students with low speaking confidence?: A qualitative study
Authors: Hirata Yoko
Published: April 2023

Purpose

This study aims to explore if and to what extent an online avatar-assisted virtual classroom can work to alleviate groups of Japanese university students’ anxiety around giving spoken presentations. It also explores how to create a more inclusive language learning environment and encourage interaction between the students in the virtual classroom.

Design/methodology/approach

A self-reported survey compares the same group of students’ responses to three learning contexts: an everyday in-person or conventional English learning classroom; an online videoconferencing-based classroom, via Zoom; and an online “virtual” or avatar-based classroom simulation, via the software “Gather”.

Findings

The findings suggest that the avatar-assisted virtual classroom helps students experience the least amount of fear and apprehension when speaking out loud in English and improves their speaking confidence. Similar to the findings in terms of everyday in-person lessons, the overwhelming majority of students attending Zoom lessons showed high levels of anxiety toward speaking out loud.

Originality/value

Challenges making use of the target language remain a persistent source of stress for Japanese students. The global shift toward online learning and the associated technologies have created opportunities to experiment with novel approaches to teaching. The discussion considers the data in the context of online classroom environments and existing speaking anxiety research. While the sample size is small, this study seeks to provide a safe and non-threatening learning environment for disadvantaged and diverse students, as well as suggestions for further research.
Translating quality criteria in university accreditation
Authors: Degn Lise , Madsen Miriam , Brøgger Katja
Published: April 2023

Purpose

The purpose of this paper is to explore how Danish higher education institutions (HEIs) navigate the demands and expectations of accreditation procedures, and how the limited freedom posed by accreditation schemes is used by HEIs by way of translation.

Design/methodology/approach

Through document studies of policy documents and the institutional self-assessment reports, the paper follows the concept of quality from the international level to the Danish national level, and onwards into the individual HEIs, where the authors examine how notions of quality are constructed through the translation of national regulation, guidelines and procedures of accreditation into the self-narratives of the self-assessment reports.

Findings

The authors find that the national guidelines for accreditation represents a complex translation of supranational guidelines by minimizing certain aspects and enhancing others. This national translation is then analyzed as the frame for the institutional translations where the analysis reveals how HEIs exercise a great deal of agency, within a quite narrow frame constituted by regulations and guidelines.

Originality/value

By using the Olivers (1991) typology of organizational responses, the authors discuss how the HEIs not only imitate and abide to institutionalized norms and concepts of quality but also reformulate, edit, omit and enhance certain elements of quality. The authors demonstrate that when accreditation meets the HEIs, it is clearly the national agendas that are most pervasive and offer the most relevant vocabulary for the HEIs.
The leopard’s spots: changing change management
Authors: Hirsch Peter Buell
Published: April 2023

Purpose

This study aims to discuss the tension between the almost universal existence of ongoing change management initiatives, the speed of C Suite transitions and the shrinking of middle management.

Design/methodology/approach

This viewpoint looks at coverage of change management initiatives and the statistics on management transitions across different industries.

Findings

The review of the data suggests that the increase in change management initiatives set against senior management instability and the shrinkage in middle management is leading to diminishing returns. The author suggests that increasing stability and consistency in core areas is becoming more important to corporate financial success.

Originality/value

While change management has been extensively studied, little attention has been paid to the juxtaposition of these initiatives with senior management fluidity and shrinking middle management resources.
Psychometric properties of the successful school leadership survey
Authors: Leithwood Kenneth , Sun Jingping , Schumacker Randall , Hua Cheng
Published: April 2023

Purpose

This study extends research on one of the most frequently cited school leadership frameworks by examining the psychometric properties of the instrument designed to assess many of the practices included in that framework.

Design/methodology/approach

Using data collected from 1,401 teachers the study examined the instrument’s measurement invariance, score reliabilities, as well as construct and predictive validities. Polytomous latent trait models (Many-Facet Rasch model), scale and principal component analysis using second-order Confirmatory Factor Analysis, and Structural Equation Modeling (SEM)-Path modelling were used for these purposes.

Findings

Findings report levels of score reliability and valid score inferences. Results concerning the predictive validity of the instrument indicate a complex set of relations among the domains of leadership practices measured by the instrument, variables selected as mediators of leaders’ influence, and their direct and indirect effects on student learning.

Research limitations/implications

This study provides researchers with a reliable and valid instrument for use in their future research. Data for the study were provided by elementary teachers in one US state. The extent to which results of the instrument are valid across different cultural and organizational settings remains to be determined.

Practical implications

Leadership developers may find the instrument useful for assessing the strengths and weaknesses of those participating in their programs while leaders themselves many find the instrument useful for self-diagnosis.

Originality/value

This study contributes to the development of school leadership measures by including Rasch modeling among the methods used for examining the instrument’s psychometric properties.