bluuebunny/crossref_metadata_2025 huggingface dataset:
Yersinia pseudotuberculosis YopE prevents uptake by M cells and instigates M cell extrusion in human ileal enteroid-derived monolayers
Authors: Fasciano Alyssa C. , Dasanayake Gaya S. , Estes Mary K. , Zachos Nicholas C. , Breault David T. , Isberg Ralph R. , Tan Shumin , Mecsas Joan
Published: August 2021

Many pathogens use M cells to access the underlying Peyer’s patches and spread to systemic sites via the lymph as demonstrated by ligated loop murine intestinal models. However, the study of interactions between M cells and microbial pathogens has stalled due to the lack of cell culture systems. To overcome this obstacle, we use human ileal enteroid-derived monolayers containing five intestinal cell types including M cells to study the interactions between the enteric pathogen, Yersinia pseudotuberculosis (Yptb) and M cells. The Yptb type three secretion system (T3SS) effector Yops inhibit host defenses including phagocytosis and are critical for colonization of the intestine and Peyer’s patches. Therefore, it is not understood how Yptb traverses through M cells to breach the epithelium. By growing Yptb under two physiological conditions that mimic the early infectious stage (low T3SS-expression) or host-adapted stage (high T3SS-expression), we found that large numbers of Yptb specifically associated with M cells, recapitulating murine studies. Transcytosis through M cells was significantly higher by Yptb expressing low levels of T3SS, because YopE and YopH prevented Yptb uptake. YopE also caused M cells to extrude from the epithelium without inducing cell-death or disrupting monolayer integrity. Sequential infection with early infectious stage Yptb reduced host-adapted Yptb association with M cells. These data underscore the strength of enteroids as a model by discovering that Yops impede M cell function, indicating that early infectious stage Yptb more effectively penetrates M cells while the host may defend against M cell penetration of host-adapted Yptb.
speedingCARs: accelerating the engineering of CAR T cells by signaling domain shuffling and single-cell sequencing
Authors: Di Roberto Raphael B. , Castellanos-Rueda Rocio , Schlatter Fabrice S. , Palianina Darya , Nguyen Oanh T.P. , Kapetanovic Edo , Hierlemann Andreas , Khanna Nina , Reddy Sai T.
Published: August 2021

Chimeric antigen receptors (CARs) consist of an extracellular antigen-binding region fused to intracellular signaling domains, thus enabling customized T cell responses against target cells. Due to the low-throughput process of systematically designing and functionally testing CARs, only a small set of immune signaling domains have been thoroughly explored, despite their major role in T cell activation, effector function and persistence. Here, we present speedingCARs, an integrated method for engineering CAR T cells by signaling domain shuffling and functional screening by single-cell sequencing. Leveraging the inherent modularity of natural signaling domains, we generated a diverse library of 180 unique CAR variants, which were genomically integrated into primary human T cells by CRISPR-Cas9. Functional and pooled screening of the CAR T cell library was performed by co-culture with tumor cells, followed by single-cell RNA sequencing (scRNA-seq) and single-cell CAR sequencing (scCAR-seq), thus enabling high-throughput profiling of multi-dimensional cellular responses. This led to the discovery of several CAR variants that retained the ability to kill tumor cells, while also displaying diverse transcriptional signatures and T cell phenotypes. In summary, speedingCARs substantially expands and characterizes the signaling domain combinations suited for CAR design and supports the engineering of next-generation T cell therapies.
Tunable Cellular Localization and Extensive Cytoskeleton-Interplay of Reflectins
Authors: Song Junyi , Liu Chuanyang , Li Baoshan , Liu Liangcheng , Zeng Ling , Ye Zonghuang , Mao Ting , Wu Wenjian , Hu Biru
Published: August 2021

Reflectin proteins are nature copolymers consist of repeated canonical domains, locating in a biophotonic system called Bragg lamellae and manipulating the dynamic structural coloration of iridocytes. Their biological functions are intriguing, but the underlying mechanism is not fully understood. In this study, reflectin A1, A2, B1 and C were found to present distinguished cyto-/nucleoplasmic localization preferences. Comparable intracellular localization can be reproduced by truncated reflectin variants, suggesting a conceivable evolutionary order among reflectin proteins. Secondly, the size-dependent access of reflectin variants into nucleus demonstrate a potential model of how reflectins get into Bragg lamellae. Thirdly, RfA1 was found to extensively interact with cytoskeleton, including its binding to actin and microtubule minus-end-directed movement. This implies cytoskeleton system plays fundamental role during the organization and transportation of reflectin proteins. Findings presented here recommend reflectins as programmable biomaterials which can be used to decipher their evolution processes, to delineate their biological mechanism, and to achieve tunable intracellular targeting as editable tags.
Viral spillover risk increases with climate change in High Arctic lake sediments
Authors: Lemieux Audrée , Colby Graham A. , Poulain Alexandre J. , Aris-Brosou Stéphane
Published: August 2021

The host spectrum of viruses is quite diverse, as they can sustainedly infect a few species to several phyla. When confronted with a new host, a virus may even infect it and transmit sustainably in this new host, a process called “viral spillover.” However, the risk of such events is difficult to quantify. As climate change is rapidly transforming environments, it is becoming critical to quantify the potential for spillovers. To address this issue, we resorted to a metagenomics approach and focused on two environments, soil and lake sediments from Lake Hazen, the largest High Arctic freshwater lake in the world. We used DNA and RNA sequencing to reconstruct the lake’s virosphere in both its sediments and soils, as well as its range of eukaryotic hosts. We then estimated the spillover risk by measuring the congruence between the viral and the eukaryotic host phylogenetic trees, and show that spillover risk is higher in lake sediments than in soil, and increases with runoff from glacier melt, a proxy for climate change. Should climate change also shift species range of potential viral vectors and reservoirs northwards, the High Arctic could become fertile ground for emerging pandemics.
Isolation and Genomics of multidrug-resistant Brevundimonas diminuta collected from patients with pertussis-like symptoms
Authors: Safarchi Azadeh , Nikbin Vajihe Sadat , Saedi Samaneh , Dinarvand Mojdeh , Sedaghatpour Mahdi , Lotfi Masoumeh Nakhost , Tay Chin Yen , Lamichhane Binit , Shahcheraghi Fereshteh
Published: August 2021

Brevundinomas diminuta is known as an opportunistic pathogen and is rarely associated with invasive infections in humans causing infection in the different parts of the body. In this study, we identified three B. diminuta isolates from three patients with an initial diagnosis of pertussis. Isolates were confirmed using biochemical tests and 16s rRNA sequencing. All isolates were resistant to three different classes of antimicrobial drugs including ceftazidime and ciprofloxacin. We performed Illumina whole-genome sequencing for two isolates. The results showed an average genome size of 3.25 Mbp with the G+C content 67% with multiple predicted virulence factors and genes leading to antibiotic resistance. We found an open pan-genome with 1502 core genes by analysing 13 available global B. diminuta isolated from different environments such as water, soil, or gentamicin fermentation residue. In the phylogenetic analysis, our isolates were grouped with B. diminuta isolate collected from an oral cavity of a patient in the USA.
Beyond body maps: information content of specific body parts is distributed across the somatosensory Homunculus
Authors: Muret Dollyane , Root Victoria , Kieliba Paulina , Clode Danielle , Makin Tamar R.
Published: August 2021

The somatosensory homunculus in primary somatosensory cortex (S1) is topographically organised, with relatively high selectivity to each body part in its primary area. This dominant feature may eclipse other organising principles in S1. Recent multivariate methodologies allow us to identify representational features beyond selectivity, e.g., information content, providing new opportunities to characterise the homunculus. Using Representational Similarity Analysis, we asked whether body part information content can be identified in S1 beyond the primary area of a given body part. Representational dissimilarities in fMRI activity patterns were compared between different body parts (face, hand and feet) and subparts (e.g., fingers), and between different actions performed with the same body part. Throughout the S1 homunculus, we identified significant dissimilarities between non-primary body parts (e.g., between the hand and the lips in the foot area). We also observed significant dissimilarities between body subparts in distant non-primary areas (e.g., different face parts in the foot area). Finally, we could significantly dissociate between two movements performed by one body part (e.g., the hand) well beyond its primary area (e.g., in the foot and face areas), even when focusing the analysis along the most topographically organised sub-region of S1, Brodmann area 3b. Altogether, our results demonstrate that body part and action-related information content is more distributed across S1 homunculus than previously considered. While this finding does not revoke the general topographic organising principle of S1, it reveals yet unexplored underlying information contents that could be harnessed for rehabilitation, as well as novel brain-machine interfaces.
SARS-CoV-2 infection induces soluble platelet activation markers and PAI-1 in the early moderate stage of COVID-19
Authors: Al-Tamimi Abaher O. , Yusuf Ayesha M. , Jayakumar Manju N. , Ansari Abdul W. , Elhassan Mona , AbdulKarim Fatema , Kannan Meganathan , Halwani Rabih , Ahmad Firdos
Published: August 2021

Introduction

Coagulation dysfunction and thromboembolism emerge as strong comorbidity factors in severe COVID-19. However, it is unclear when particularly platelet activation markers and coagulation factors dysregulated during the pathogenesis of COVID-19. Here, we sought to assess the levels of coagulation and platelet activation markers at moderate and severe stages of COVID-19 to understand the pathogenesis.

Methods

To understand this, hospitalized COVID-19 patients with (severe cases that required intensive care) or without pneumonia (moderate cases) were recruited. Phenotypic and molecular characterizations were performed employing basic coagulation tests including PT, APTT, D-Dimer and TFPI. The flow cytometry-based multiplex assays were performed to assess FXI, anti-thrombin, prothrombin, fibrinogen, FXIII, P-selectin, sCD40L, plasminogen, tissue-plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) and D-Dimer.

Results

The investigations revealed induction of plasma P-selectin and CD40 ligand (sCD40L) in moderate COVID-19 cases which were significantly abolished with the progression of COVID-19 severity. Moreover, a profound reduction in plasma tissue factor pathway inhibitor (TFPI) and FXIII were identified particularly in the severe COVID-19. Further analysis revealed fibrinogen induction in both moderate and severe patients. Interestingly, an elevated PAI-1 more prominently in moderate, and tPA particularly in severe COVID-19 cases were observed. Particularly, the levels of fibrinogen and tPA directly correlated with the severity of the disease.

Conclusions

In summary, induction of soluble P-selectin, sCD40L, fibrinogen and PAI-1 in moderate COVID-19 cases suggests the activation of platelets and coagulation system before patients require intensive care. These findings would help in designing better thromboprophylaxis to limit the COVID-19 severity.
Counterbalance of Foxp3 and IDO expression at different tumor stages in aggressive breast cancer subtypes
Authors: Canzoneri Romina , Lacunza Ezequiel , Rabassa Martín E. , Cavalli Fiorella A. , Ferretti Valeria , Barbera Luis A. , Cretón Aldo , Croce Maria Virginia , Larrain Marina T. Isla
Published: August 2021

Foxp3 and IDO1 are known immunomodulatory molecules involved in tumor escape and could be related to tumor infiltrating lymphocytes (TILs) in the tumor microenvironment. In this study, tumoral Foxp3 and IDO1 expression in breast cancer were evaluated in relation to lymphocyte biomarkers such as CD8 and CD45R0, regulatory T cells, as well as intratumoral and stromal TILs (iTILs and sTILs, respectively). Clinical and histopathological features were also included in the analysis. Foxp3 and IDO1 were found in tumor cells showing mainly cytoplasmic patterns in 60% and 62% tumor samples, respectively. TILs were found in 76% of samples; iTILs were detected in 92% of those samples and sTILs in 55%. Foxp3+ TILs were detected only in 12% of TILs+ samples associated with tumoral Foxp3 expression. Tumoral Foxp3 was mainly expressed at lower tumor stages while IDO1 expression was associated with advanced tumor stages; both correlated with CD8+ TILs which were observed in 77% of TILs+ samples. CD45R0+ were observed in 81% of TILs+ samples and correlated with higher tumor stages and poorly differentiated tumors. In ER negative tumors, an inverse correlation between Foxp3 and IDO1 tumoral expression was found in relation to tumor stage. TNBC subtype showed a positive correlation with the presence of iTILs. In silico analysis showed that Foxp3 and coexpressed genes in breast cancer were associated with immune response genes. Foxp3 was found predominantly in Basal and Her2-enriched subtypes in relation to Luminal A subtype, by RNA seq and RNA microarray database analysis. In conclusion, the expression of Foxp3 and IDO1 in tumors at different stages suggests a potential compensatory mechanism to evade the strong CTL response observed. This is relevant since the cumulative data indicates that Foxp3 as well as IDO1 could be potential targets of immunotherapy in patients with tumors at different stages and for the most aggressive breast cancer subtypes such as TNBC and Her2-enriched.

HIGHLIGHTS

Foxp3 and IDO1 were found overexpressed in the cytoplasm of tumor cells, observed in BC samples at early or advanced tumor stages, respectively, both associated with abundant cytotoxic CD8+ lymphocytes infiltrates.

Tumor immunosuppression by Foxp3 and IDO1 tumoral expression could counteract the attempt of the host’s immune system to eradicate the tumor by CD8+ and CD45R0+ TILs cytotoxic activity.

It is well-known the tolerogenic role of Foxp3 in Treg and less understood the role of Foxp3 in tumors. However, there is increasing evidence that Foxp3+ tumor cells appear to promote an immunosuppressive microenvironment similar to Treg. Whether this is a consequence of the effect of other immunosuppressive factors secreted by the tumor cells which can be induced by Foxp3 expression, such as TGFβ, remains to be determined.
Rates of convergence in the two-island and isolation-with-migration models
Authors: Legried Brandon , Terhorst Jonathan
Published: August 2021

A number of powerful demographic inference methods have been developed in recent years, with the goal of fitting rich evolutionary models to genetic data obtained from many populations. In this paper we investigate the statistical performance of these methods in the specific case where there is continuous migration between populations. Compared with earlier work, migration significantly complicates the theoretical analysis and demands new techniques. We employ the theories of phase-type distributions and concentration of measure in order to study the two-island and isolation-with-migration models, resulting in both upper and lower bounds. For the upper bounds, we consider inferring rates of coalescent and migration on the basis of directly observing pairwise coalescent times, and, more realistically, when (conditionally) Poisson-distributed mutations dropped on latent trees are observed. We complement these upper bounds with information-theoretic lower bounds which establish a limit, in terms of sample size, below which inference is effectively impossible.
Time Evolution of the Stroke Symptom-Herb Networks Based on TCM Prescriptions
Authors: Fu Xing , Li Qianqian , Yang Feng , Zhou Ranran , Li Ran , Hou Jianchen , Tao Xiaohua
Published: August 2021

Traditional Chinese Medicine (TCM) has its origins in distant antiquity and has piled up over a long time with much knowledge about diseases, especially stroke. Different combinations of symptom variables yield different combinations of herbs to form a myriad of prescriptions, and they have undergone repeated confirmation and are worthy objects of excavation and analysis. Herbal studies on stroke have developed from genomics to transcriptomics, proteomics and metabolomics, yet more thought is needed on putting time in a wider perspective of the symptoms and herbs for stroke in Chinese medicine.

Due to this, we studied the dynamic structure of TCM prescriptions on stroke, using over 270 TCM prescription books containing 2231 prescriptions related to stroke recorded from 341 to 2000 CE. We labeled the functions of the prescriptions with the symptoms based on subject terms in MESHNeurologic Manifestations, then standardized the herbs in the prescriptions, and finally connected the co-occurring symptoms and herbs in the prescriptions to build an undirected complex network. The Stroke Symptom-Herb Networks (SSHNs) can be seen from its network characteristics that it is not a random network and has small-world characteristics. It has experienced two peaks in its nearly 1700-year history, during the Song dynasty, the Ming and Qing dynasties. From 600 years onwards, the core herb cluster has been initially formed. The comparison of sub-network similarities allowed us to identify several symptoms with similar herb clusters.

We divided the community based on modularity, and by analyzing the community evolution, we found a more fixed historical evolutionary trend withHemiplegiaandSialorrheanodes and their associated symptom and herb nodes. In the time series analysis, we found many symptom-herb combinations that were consistently closely related to historic time depends on assessing the similarity between the symptoms and the herbs. The complex network provides a distinctive perspective for understanding the symptom-herb relationships embedded in TCM prescriptions in remote antiquity.
Directed Differentiation of Human Pluripotent Stem Cells into Radial Glia and Astrocytes Bypasses Neurogenesis
Authors: Jovanovic Vukasin M. , Malley Claire , Tristan Carlos A. , Ryu Seungmi , Chu Pei-Hsuan , Barnaeva Elena , Ormanoglu Pinar , Mercado Jennifer Colon , Michael Sam , Ward Michael E. , Simeonov Anton , Singeç Ilyas
Published: August 2021

Derivation of astrocytes from human pluripotent stem cells (hPSCs) is inefficient and cumbersome, impeding their use in biomedical research. Here, we developed a highly efficient chemically defined astrocyte differentiation strategy that overcomes current limitations. This approach largely bypasses neurogenesis, which otherwise precedes astrogliogenesis during brain development and in vitro experiments. hPSCs were first differentiated into radial glial cells (RGCs) exhibiting in vivo-like radial glia signatures. Activation of NOTCH and JAK/STAT pathways in bona fide RGCs resulted in direct astrogliogenesis confirmed by expression of various glial markers (NFIA, NFIB, SOX9, CD44, S100B, GFAP). Transcriptomic and genome-wide epigenetic analyses confirmed RGC-to-astrocyte differentiation and absence of neurogenesis. The morphological and functional identity of hPSC-derived astrocytes was confirmed by using an array of methods (e.g. electron microscopy, calcium imaging, co-culture with neurons, grafting into mouse brains). Lastly, the scalable protocol was adapted to a robotic platform and used to model Alexander disease. In conclusion, our findings uncover remarkable plasticity in neural lineage progression that can be exploited to manufacture large numbers of human hPSC-derived astrocytes for drug development and regenerative medicine.
Profiling Transcription Initiation in Peripheral Leukocytes Reveals Severity-Associated Cis-Regulatory Elements in Critical COVID-19
Authors: Lam Michael Tun Yin , Duttke Sascha H. , Odish Mazen F. , Le Hiep D. , Hansen Emily A. , Nguyen Celina T. , Trescott Samantha , Kim Roy , Deota Shaunak , Chang Max W. , Patel Arjun , Hepokoski Mark , Alotaibi Mona , Rolfsen Mark , Perofsky Katherine , Warden Anna S. , Foley Jennifer , Ramirez Sydney I , Dan Jennifer M. , Abbott Robert K , Crotty Shane , Crotty Alexander Laura E , Malhotra Atul , Panda Satchidananda , Benner Christopher W. , Coufal Nicole G.
Published: August 2021

The contribution of transcription factors (TFs) and gene regulatory programs in the immune response to COVID-19 and their relationship to disease outcome is not fully understood. Analysis of genome-wide changes in transcription at both promoter-proximal and distal cis-regulatory DNA elements, collectively termed the ’active cistrome,’ offers an unbiased assessment of TF activity identifying key pathways regulated in homeostasis or disease. Here, we profiled the active cistrome from peripheral leukocytes of critically ill COVID-19 patients to identify major regulatory programs and their dynamics during SARS-CoV-2 associated acute respiratory distress syndrome (ARDS). We identified TF motifs that track the severity of COVID- 19 lung injury, disease resolution, and outcome. We used unbiased clustering to reveal distinct cistrome subsets delineating the regulation of pathways, cell types, and the combinatorial activity of TFs. We found critical roles for regulatory networks driven by stimulus and lineage determining TFs, showing that STAT and E2F/MYB regulatory programs targeting myeloid cells are activated in patients with poor disease outcomes and associated with single nucleotide genetic variants implicated in COVID-19 susceptibility. Integration with single-cell RNA-seq found that STAT and E2F/MYB activation converged in specific neutrophils subset found in patients with severe disease. Collectively we demonstrate that cistrome analysis facilitates insight into disease mechanisms and provides an unbiased approach to evaluate global changes in transcription factor activity and stratify patient disease severity.
Suppressor of Fused regulation of Hedgehog Signaling is Required for Proper Astrocyte Differentiation
Authors: Spice Danielle M. , Dierolf Joshua , Kelly Gregory M.
Published: August 2021

Hedgehog signaling is essential for vertebrate development, however, less is known about the negative regulators that influence this pathway. Using the mouse P19 embryonal carcinoma cell model, Suppressor of Fused (SUFU), a negative regulator of the Hedgehog pathway, was investigated during retinoic acid-induced neural differentiation. We found Hedgehog signaling was activated in the early phase of differentiation but was inactive during terminal differentiation of neurons and astrocytes. Early activation was required for neural differentiation however, it alone was not sufficient to induce neural lineages. SUFU, which regulates signaling at the level of GLI, remained relatively unchanged during differentiation, but its loss through CRISPR-Cas9 gene editing resulted in ectopic expression of Hedgehog target genes. Interestingly, these SUFU-deficient cells were unable to differentiate without retinoic acid, and when used they showed delayed and decreased astrocyte differentiation; neuron differentiation was unaffected. Ectopic activation of Hh target genes in SUFU-deficient cells remained throughout retinoic acid-induced differentiation and this was accompanied by the loss of GLI3, despite the presence of the Gli3 message. Thus, the study indicates the proper timing and proportion of astrocyte differentiation requires SUFU, and its normal regulation of GLI3 to maintain Hh signaling in an inactive state.
Low-temperature crystal structure of 4-chloro-1H-pyrazole
Authors: Rue Kelly , Raptis Raphael G.
Published: August 2021

The structure of 4-chloro-1H-pyrazole, C3H3ClN2, at 170 K has orthorhombic (Pnma) symmetry and is isostructural to its bromo analogue. Data were collected at low temperature since 4-chloro-1H-pyrazole sublimes when subjected to the localized heat produced by X-rays. The structure displays intermolecular N—H...N hydrogen bonding and the packing features a trimeric molecular assembly bisected by a mirror plane (m normal to b) running through one chlorine atom, one carbon atom and one N—N bond. The asymmetric unit therefore consists of one and one-half 4-chloro-1H-pyrazole molecules. Thus, the N—H proton is crystallographically disordered over two positions of 50% occupancy each.
The effects of overconfident yield forecasting on cross-coverage level crop insurance demand
Authors: Michaud Clayton P.
Published: August 2021

Purpose

This paper examines the effect of overconfident yield forecasting (optimism bias) on crop insurance coverage level choices across both yield and revenue insurance.

Design/methodology/approach

This study simulates a representative producer’s preferred coverage level for both yield and revenue insurance under three potential models of decision-making and four potential manifestations of overconfident yield forecasting. The study then uses this framework to examine how coverage level choices change as overconfidence increases (decreases).

Findings

As overconfidence increases, producers prefer lower levels of crop insurance coverage than they would otherwise prefer, with extreme overconfidence inducing farmers to buy no insurance at all. While overconfidence affects cross-coverage demand for revenue and yield insurance similarly, this effect is more pronounced for yield insurance. Cross-coverage level demand for revenue insurance is relatively stable across changes in the correlation between prices and yields.

Practical implications

This research has important implications for crop insurance subsidy design and crop insurance demand modeling.

Originality/value

There is a growing body of literature suggesting that producers are overconfident with regard to their future yield risk and that this bias reduces their willingness to pay for risk management tools such as crop insurance. This is the first study to look at how such overconfidence affects cross-coverage level demand for crop insurance.
From rationale to lessons learned in the cloud information security risk assessment: a study of organizations in Sweden
Authors: Faizi Ana , Padyab Ali , Naess Andreas
Published: August 2021

Purpose

This study aims to address the issue of practicing information security risk assessment (ISRA) on cloud solutions by studying municipalities and large organizations in Sweden.

Design/methodology/approach

Four large organizations and five municipalities that use cloud services and conduct ISRA to adhere to their information security risk management practices were studied. Data were gathered qualitatively to answer the study’s research question: How is ISRA practiced on the cloud? The Coat Hanger model was used as a theoretical lens to study and theorize the practices.

Findings

The results showed that the organizations aimed to follow the guidelines, in the form of frameworks or their own experience, to conduct ISRA; furthermore, the frameworks were altered to fit the organizations’ needs. The results further indicated that one of the main concerns with the cloud ISRA was the absence of a culture that integrates risk management. Finally, the findings also stressed the importance of a good understanding and a well-written legal contract between the cloud providers and the organizations using the cloud services.

Originality/value

As opposed to the previous research, which was more inclined to try out and evaluate various cloud ISRA, the study provides insights into the practice of cloud ISRA experienced by the organizations. This study represents the first attempt to investigate cloud ISRA that organizations practice in managing their information security.
Comparative analysis of three categories of four-DOFs exoskeleton mechanism based on relative movement offsets
Authors: Cao Qiang , Li Jianfeng , Dong Mingjie
Published: August 2021

Purpose

The purpose of this paper is to evaluate three categories of four-degrees of freedom (4-DOFs) upper limb rehabilitation exoskeleton mechanisms from the perspective of relative movement offsets between the upper limb and the exoskeleton, so as to provide reference for the selection of exoskeleton mechanism configurations.

Design/methodology/approach

According to the configuration synthesis and optimum principles of 4-DOFs upper limb exoskeleton mechanisms, three categories of exoskeletons compatible with upper limb were proposed. From the perspective of human exoskeleton closed chain, through reasonable decomposition and kinematic characteristics analysis of passive connective joints, the kinematic equations of three categories exoskeletons were established and inverse position solution method were addressed. Subsequently, three indexes, which can represent the relative movement offsets of human–exoskeleton were defined.

Findings

Based on the presented position solution and evaluation indexes, the joint displacements and relative movement offsets of the three exoskeletons during eating movement were compared, on which the kinematic characteristics were investigated. The results indicated that the second category of exoskeleton was more suitable for upper limb rehabilitation than the other two categories.

Originality/value

This paper has a certain reference value for the selection of the 4-DOFs upper extremity rehabilitation exoskeleton mechanism configurations. The selected exoskeleton can ensure the safety and comfort of stroke patients with upper limb dyskinesia during rehabilitation training.
The Giotto's Bell Tower at Firenze (Italy): foundation assessment
Authors: Coli Massimo , Tanganelli Marco , Baldi Michele , Viti Stefania
Published: August 2021

Purpose

The paper is aimed at assessing the safety of the Giotto's Bell Tower, with special attention to its foundation system, i.e. the foundation works and soil. The tower, well known all over the world, has a squared plan, with sides of 14.45 m each, and a total height equal to 84.7 m. The structural response of the tower is assessed with reference to the gravitational load and to the expected seismic action, quantified according to the seismic hazard of the site and the foundation soil.

Design/methodology/approach

A simplified analysis has been performed to check the safety level of the tower to seismic actions. Special attention has been paid to quantify the horizontal actions representing the seismic loads. Such quantification, indeed, has been made both through the elastic spectrum of the tower and by performing a site response analysis on the foundation soil, represented as a one-dimensional stratification of soil layers, described on the basis of experimental investigations. After defining the loading actions, a simplified assessment of the foundation safety has been made by considering the action over foundation, the geotechnical data and the safety factor.

Findings

The findings of the paper concern the assessment of the safety of the tower's foundation system. A lot of experimental data on the foundation soil, provided by various geological investigations, have been provided and used for the assessment. Moreover, the mechanical properties of the materials used for the structure have been collected and shown in the paper.

Originality/value

The paper collects a lot of technical information regarding the Giotto's Bell Tower, both regarding its foundation soil and the constituting materials. On the basis of the collected information, a structural analysis has been made to assess the seismic safety of the tower, and the results of such assessment are provided and discussed.
Exploring critical success factors (CSFs) of humanitarian supply chain management (HSCM) in flood disaster management (FDM)
Authors: Damoah Isaac Sakyi
Published: August 2021

Purpose

This study explores the critical success factors (CSFs) in humanitarian supply chain management (HSCM) by focussing on flood disaster management (FDM) in Ghana.

Design/methodology/approach

An in-depth semi-structured interview and questionnaire surveys in a sequential data collection approach were used to collect data from definitive stakeholders of humanitarian organisations. The data was analysed using exploratory factor analysis (EFA), confirmatory factors analysis (CFA) and structural equation modelling (SEM) techniques.

Findings

Seventy-four factors were identified as success factors of HSCM of flood disaster management. However, 41 of these factors were statistically significant and considered as critical. In descending order, these factors relate to management practices, education and training, stakeholder involvement and cooperation, infrastructure, innovation and technology, materials and resources, administrative practices, socio-cultural and economic. Whilst some factors are internal to the humanitarian organisations, others are external factors that are beyond the control of humanitarian organisations.

Research limitations/implications

Even though this study offers empirical results that could guide policymakers in their decision-making about humanitarian operations, care needs to be taken since the data is within one country and within a specific disaster context – hence, policymakers need to consider the local contextual dynamics. Future studies could look at different disasters context to make a comparative analysis of various types of disaster operations.

Practical implications

Institutions such as World Health Organization, Red Cross organisations and UN seeking to curbs global-warming-related disasters and the reduction of the effects of flood disaster can use findings as a guide during the formulation of HSCM policies and strategies.

Originality/value

Unlike previous studies of humanitarian operations that focussed extensively on theoretical expositions, simulations, conceptual frameworks and models, this present study offers empirical evidence of humanitarian operations in the context of SCM. Further, by highlighting on the HSCM CSFs, this study contributes to disaster reduction and their effects on humanity in the context of FDM. This research could be used as guide by governments and FDM organisations to make informed decisions on SCM areas to focus the most during FDM.
Intellectual capital on performance: a meta-analysis study enhancing a new perspective of the components
Authors: Pigola Angélica , De Santi Pedro Victor , da Costa Priscila Rezende , Storopoli Jose
Published: August 2021

Purpose

The authors examined intellectual capital (IC) components, namely human, structural and relational capital, on firm performance (FP) and innovation performance (IP), while also examining the role of knowledge management (KM) in this context.

Design/methodology/approach

The authors employed a meta-analysis using 81 studies from 2006 to 2020 using bivariate analysis, meta-analytic structure equation modeling (MASEM) and fuzzy-set qualitative comparative analysis (fsQCA) to study IC components on FP and IP.

Findings

The MASEM results show that IC affects positively on FP, but not in a significant level and affects positively and significantly on IP. The findings also reveal that the moderation effect of KM affects positively on FP but not on IP. Additionally, the fsQCA analysis shows that KM and its multidimensional role has a positive impact on FP and IP and has a potential to be consistent as a dynamic component for IC.

Research limitations/implications

The results may be limited by different statistical biases and inverse causality issues or associated with contextualities related to the studies of the sample selected by our criteria.

Practical implications

Managers can identify the appropriate IC elements and act accordingly. The study suggests that mobilizing human, structural, relational and knowledge capital must begin from the firms' birth and continue further during firms' stages of the business.

Social implications

IC is the bridge of evolution for future societies. Knowing how its components impact all levels of corporate environment indirectly influences how societies build up their social bases and policies to fulfill new professional generations.

Originality/value

By using the MASEM and fsQCA, the authors have more detailed insights into the multidimensional context of KM in IC components on firm and innovation performance identifying configurations of intangible resources.
Predicting business processes of the social insurance using recurrent neural network and Markov chain
Authors: Fadaei PellehShahi Mehrdad , Kordrostami Sohrab , Refahi Sheikhani Amir Hossein , Faridi Masouleh Marzieh
Published: August 2021

Purpose

Predicting the final status of an ongoing process or a subsequent activity in a process is an important aspect of process management. Semi-structured business processes cannot be predicted by precise and mathematical methods. Therefore, artificial intelligence is one of the successful methods. This study aims to propose a method that is a combination of deep learning methods, in particular, the recurrent neural network and Markov chain.

Design/methodology/approach

The proposed method applies the BestFirst algorithm for the search section and the Cfssubseteval algorithm for the feature comparison section. This study focuses on the prediction systems of social insurance and tries to present a method that is less costly in providing real-world results based on the past history of an event.

Findings

The proposed method is simulated with real data obtained from Iranian Social Security Organization, and the results demonstrate that using the proposed method increases the memory utilization slightly more than the Markov method; however, the CPU usage time has dramatically decreased in comparison with the Markov method and the recurrent neural network and has, therefore, significantly increased the accuracy and efficiency.

Originality/value

This research tries to provide an approach capable of producing the findings closer to the real world with fewer time and processing overheads, given the previous records of an event and the prediction systems of social insurance.
Education focused pracademics on twitter: building democratic fora
Authors: Kolber Steven , Heggart Keith
Published: August 2021

Purpose

This paper explores the features of pracademic practice within online spaces where pracademics, academics and teachers interact.

Design/methodology/approach

This paper uses autoethnographic case studies to showcase the boundary-spanning thinking of two pracademics, one a practicing teacher, the other an early career researcher, to provide an overview of how pracademics are engaging with research and the profession online in Australia, in 2021.

Findings

The paper describes five key features that are central to the development of pracademic practice. They are rigour and depth, discussion beyond immediate cultural context, accessibility, knowledge creation and collaboration.

Research limitations/implications

This paper is focused on the teacher and early career researcher perspectives on pracademia, due to the extant literature focusing on the well-established academic perspective primarily. It focuses on fora within the Twitter social media platform and the #edureading group specifically. The authors propose that the use of Twitter fora, as those outlined, provides a legitimate form of professional development, and does contribute to the development of pracademics.

Originality/value

This piece itself is an output of pracademia; through the writing of this paper, the authors show that pracademia is possible through teacher and researcher collaboration. The focus on online spaces, pracademic teachers and a coverage of what's occurring provide a new agenda for further research and consideration.
Performance measurement in Islamic microfinance institutions: does it change social norms and values?
Authors: Abdul Zalim Siti Nazariah
Published: August 2021

Purpose

The purpose of this paper is to examine the influence of financial performance measures on the social norms and values of an Islamic microfinance institution (IMFI), and the actions taken by the organisational members to maintain these values in their organisation.

Design/methodology/approach

A qualitative case study of an NGO-based IMFI in Malaysia was undertaken, with interviews conducted with officers and managers at various organisational levels of the IMFI. Insights gained from institutional work and institutional logic were used to theorise the findings.

Findings

The IMFI used mainly financial measures to manage its performance, which were interlinked with the commercialisation approach in the industry, and the top management’s focus on the financial sustainability of the organisation. The lack of social goals and the use of reward-based financial measures did not weaken the solidified social values at the operational level, due to the independence of the operational units, the compartmentalisation of profit-making activities and the institutional work of the operational managers. The operational managers acted as carriers of this social logic. Religious values formed the pillar of the permanence of social values in the IMFI.

Originality/value

This study provides insights into the internal practices of IMFIs, and the role of religious values in the permanence of social logic in the context of an NGO-based IMFI. The lack of measurable social goals, as well as their rewards, does not compromise the focus on poverty alleviation and community development in view of the intrinsic rewards and accountability of the operational managers.
3D printing of Portland cement-containing bodies
Authors: Ur Rehman Asif , Sglavo Vincenzo M.
Published: August 2021

Purpose

Recent advances in 3D printing construction elements have focused on ordinary Portland cement (OPC) concrete using polymeric binders; herein, this study aims to produce the same using pure water.

Design/methodology/approach

A binder jet printer prototype was used to fabricate specimens that are used to assess geometric and mechanical properties. Two distinct water-based binder formulations, compatible with OPC chemistry and piezoelectric jetting device, were used: pure water and water-polyvinyl alcohol (98:2 w/w) solution.

Findings

This study examines the effect of binder flow rate on dimensional accuracy. Furthermore, the changes in the mechanical properties over time with hydration have been investigated.

Practical implications

Results indicate that the increase in mechanical strength of Portland cement concrete with pure water was consistent; however, it was delayed by the water: PVA (98:2 w/w) solution. Post-curing by water vapor hardened the structure with the removal of layering native to 3DP and decreased infilling porosity by diffusion mechanism.

Originality/value

This paper has used pure water jetting for BJT of Portland cement-containing bodies.
3 D printing technology and experimental study of chitosan gel using atomized solidification liquid-assisted extrusion molding
Authors: Wang Yangwei , Lv Peilun , Li Jian , Yu Liying , Yuan Guodong , Guo Yanling
Published: August 2021

Purpose

This paper aims to propose a suitable atomizing solidification chitosan (CS) gel liquid extrusion molding technology for the three dimensional (3D) printing method, and experiments verify the feasibility of this method.

Design/methodology/approach

This paper mainly uses experimental means, combined with theoretical research. The preparation method, solidification forming method and 3D printing method of CS gel solution were studied. The CS gel printing mechanism and printing error sources are analyzed on the basis of the CS gel ink printing results, printing performance with different ratios of components by constructing a gel print prototype, experiments evaluating the CS gel printing technology and the effects of the process parameters on the scaffold formation.

Findings

CS printing ink was prepared; the optimal formula was found; the 3 D printing experiment of CS was completed; the optimal printing parameters were obtained; and the reliability of the forming prototype, printing ink and gel printing process was verified, which allowed for the possibility to apply the 3 D printing technology to the manufacturing of a CS gel structure.

Originality/value

This study can provide theoretical and technical support for the potential application of CS 3 D printed gels in tissue engineering.
The impact of ownership structure on corporate social responsibility: the moderating role of financial performance
Authors: Dakhli Anissa
Published: August 2021

Purpose

The purpose of this paper is to investigate the relationship between ownership structure and corporate social responsibility (CSR). Specifically, this paper examines the impact of financial performance on the relationship between ownership structure and CSR.

Design/methodology/approach

This study uses panel data set of 200 French firms listed during 2007–2018 period. The direct and moderating effects were tested by using multiple regression technique.

Findings

The results indicate that investors have different attitudes toward CSR engagement. While institutional ownership affects positively CSR engagement, managerial ownership shows a negative effect. Findings also show that financial performance accentuates these effects.

Research limitations/implications

The findings have practical implications that may be useful to regulators and managers interested in enhancing CSR. For regulators, the results advise policymakers to restrict managerial ownership and promote institutional investments to improve CSR. For managers, the results suggest developing more sophisticated intervention mechanisms to deal with conflicting voices that could result from different owners’ attitudes toward CSR. As an extension to this research, further study can examine the impact of audit quality on CSR.

Originality/value

This study proposes the establishment of dynamic links between ownership structure and CSR around firm financial performance. In addition, it investigates not only the overall CSR ratings but also each of CSR pillars, namely, environmental, social and governance.
Engaging consumers through firm-generated content on Instagram
Authors: Ballester Estefania , Ruiz Carla , Rubio Natalia
Published: August 2021

Purpose

The purpose of this paper is to analyse the impact of consumers’ perceptions of the enjoyment and originality of firm-generated content (FGC) posted on Instagram on affective customer engagement (CE). In addition, an examination is undertaken of affective CE as a driver of customer behaviour.

Design/methodology/approach

The paper takes a quantitative approach using a sample of 334 women followers of an eco-friendly restaurant Instagram account. After validation of the measurement scales, the hypotheses were tested through structural equation modelling. Drawing on the stimuli-organism-response framework the authors posit that consumers’ perceptions of the enjoyment and originality of Instagram posts generate affective CE, which, in turn, influences customer behaviour.

Findings

The results showed that the perceived enjoyment and perceived originality of Instagram posts generated by an eco-friendly restaurant have a positive influence on affective CE, which, in turn, affects consumers’ recommendation behaviours, intention to follow the restaurant’s advice on Instagram and intention to revisit the restaurant.

Originality/value

This research provides novel insights into how the perceived enjoyment and originality of FGC posted on Instagram increases women’s affective engagement and expands knowledge of how affective CE might increase positive electronic word-of-mouth, intention to follow the restaurant’s advice and repurchase intentions.