bluuebunny/crossref_metadata_2025 huggingface dataset:
Xenogeneic Skin Transplantation Promotes Angiogenesis and Tissue Regeneration Through Vitamin D-Activated Trem2+ Macrophages
Authors: Henn Dominic , Chen Kellen , Fehlmann Tobias , Sivaraj Dharshan , Maan Zeshaan N. , Bonham Clark A. , Barrera Janos A. , Mays Chyna J. , Greco Autumn H. , Moortgat Illouz Sylvia E. , Lin John Qian , Foster Deshka S. , Padmanabhan Jagannath , Momeni Arash , Nguyen Dung , Wan Derrick C. , Kneser Ulrich , Januszyk Michael , Keller Andreas , Longaker Michael T. , Gurtner Geoffrey C.
Published: February 2021

Skin allo- and xenotransplantation are the standard treatment for major burns when donor sites for autografts are not available and have been shown to significantly accelerate wound healing. Although the cellular elements of foreign grafts are rejected, the extracellular matrix components integrate into the wound and may underlie their beneficial effects on wound healing. The molecular mechanisms defining the relationship between the immune response to foreign grafts and their impact on wound healing have not been fully elucidated. Here, we investigated changes in collagen architecture after xenogeneic implantation of clinically available human biologic scaffolds. We show that collagen deposition in response to the implantation of human split-thickness skin grafts (hSTSG) containing live cells recapitulates normal skin architecture, whereas human acellular dermal matrix (ADM) grafts led to highly aligned collagen deposition, characteristic of fibrosis and scar. Using single-cell RNA-sequencing, we show that macrophage differentiation in response to hSTSG is driven by vitamin D (VD) signaling toward Trem2+ subpopulations with an enrichment of pro-angiogenic and anti-fibrotic transcriptomic programs. We subsequently induced this regenerative subpopulationin vitroby treating bone marrow-derived cells with vitamin D3 and found that hydrogel delivery of Trem2+ macrophages significantly accelerated wound closure in a human-like murine excisional wound model. Our study identifies the preclinical therapeutic potential of Trem2+ macrophages to mitigate fibrosis and promote wound healing and provides a novel effective strategy to develop advanced cell therapies for complex wounds.

One Sentence Summary

Vitamin D-activated Trem2+ macrophages promote angiogenesis and mitigate fibrosis, providing a novel effective strategy to develop advanced cell therapies for complex wounds.
Growth response and recovery ofCorynebacterium glutamicumcolonies on single-cell level upon defined pH stress pulses
Authors: Täuber Sarah , Blöbaum Luisa , Wendisch Volker F. , Grünberger Alexander
Published: February 2021

Bacteria respond to pH changes in their environment via pH homeostasis to keep the intracellular pH as constant as possible within a small range. A change of the intracellular pH value influences e.g., the enzyme activity, protein stability, solubility of trace elements and the proton motive force. Here, the speciesCorynebacterium glutamicumhas been chosen as a neutralophilic and moderately alkali-tolerant bacterium capable of maintaining an internal pH of 7.5 ± 0.5 in environments with an external pH between 5.5 and 9. In the recent years, the phenotypic response ofC. glutamicumto pH changes has been systematically investigated at the bulk population level. A detailed understanding of theC. glutamicumcell responding to defined short-term pH perturbations/ pulses is missing. In this study, dynamic microfluidic single-cell cultivation (dMSCC) was applied to analyse the physiological growth response ofC. glutamicumupon precise pH stress pulses at a single-cell level. Analysis of the growth behaviour at the colony level by dMSCC exposed to single pH stress pulses (pH = 4, 5, 10, 11) revealed a decrease in the viability with increasing stress duration. Colony regrowth was possible after increasing lag phases when stress durations were increased from 5 min to 9 h for all tested pH values. Furthermore, the single-cell analysis revealed heterogeneous regrowth of cells after pH stress, which can be distinguished into two distinct behaviours firstly, cells continue to grow without interruption after the pH stress, and secondly, some cells rest for several hours after the pH stress before they start to grow again after this lag phase. This study provides the first insights into the single-cell response to acidic and alkaline pH stress adaptation ofC. glutamicum.
Biomechanical evaluation of a novel orthogonal angle-stable interlocking nail in a canine femur model Novel orthogonal angle-stable interlocking nail
Authors: Lucena D. V. F. , Minto B. W. , Rocha T. A. S. S. , Malta C. A. S. , Galíndez J. A. S. , Dias L. G. G. G.
Published: February 2021

Interlockings nails (IN) are orthopedic implants with superior mechanical and, potentially, biological qualities. Despite the countless and indisputable advantages of current angle-stable models, there are still limitations for their use in certain scenarios. The objective of the present study was to describe and biomechanically test a new orthogonal angle-stable intramedullary nail model for veterinary use. The proposed orthogonal angle-stable nail has two 3.8-mm threaded cylindrical holes in each of its portions: in the proximal portion, the holes are 11 mm apart; in the distal portion, the penultimate orifice is positioned at 90 degrees in relation to the last one, with a distance of 5.5 mm between them. The novel orthogonal nail (Group 3 – G3) was evaluated and compared biomechanically with the conventional interlocking nail (Group 1 – G1) and the uniplanar angle-stable nail (Group 2 – G2) by means of destructive torsion and axial compression tests. No statistically significant differences were observed in torsion resistance between the groups in the destructive tests. However, statistical differences were found in stiffness values in the compression tests between the orthogonal (G3) and conventional interlocking (G1) nails (p=0.01) and also between the uniplanar (G2) and interlocking (G1) nails (p=0.001). The new orthogonal nail proved to be biomechanically similar to the uniplanar angle-stable model and superior to the conventional nail. This new arrangement of interlocking screws (orthogonal and closer to each other) potentially enables the fixation of small fragments and at the extremities of long bones in dogs. Nonetheless, further clinical studies are necessary to validate such hypotheses.
Choice of method of place cell classification determines the population of cells identified
Authors: Grijseels D.M. , Shaw K. , Barry C. , Hall C.N.
Published: February 2021

Place cells, spatially responsive hippocampal cells, provide the neural substrate supporting navigation and spatial memory. Historically most studies of these neurons have used electrophysiological recordings from implanted electrodes but optical methods, measuring intracellular calcium, are becoming increasingly common. Several methods have been proposed as a means to identify place cells based on their calcium activity but there is no common standard and it is unclear how reliable different approaches are. Here we tested three methods that have previously been applied to two-photon hippocampal imaging or electrophysiological data, using both model datasets and real imaging data. These methods use different parameters to identify place cells, including the peak activity in the place field, compared to other locations (the Peak method); the stability of cells’ activity over repeated traversals of an environment (Stability method); and a combination of these parameters with the size of the place field (Combination method). The three methods performed differently from each other on both model and real data. The Peak method showed high sensitivity and specificity for detecting model place cells and was the most robust to variations in place field width, reliability and field location. In real datasets, vastly different numbers of place cells were identified using the three methods, with little overlap between the populations identified as place cells. Therefore, choice of place cell detection method dramatically affects the number and properties of identified cells. We recommend the Peak method be used in future studies to identify place cell populations, unless there is an explicit theoretical reason for detecting cells with more narrowly defined properties.

Author Summary

Place cells are hippocampal cells that have spatially constrained receptive fields, the place field. These cells have been widely studied in the context of navigation, more recently using virtual reality environments in combination with optical methods of recording neuronal activity. However, there is a lack of consensus regarding how to identify place cells in these data. In this study we tested the sensitivity and specificity of three methods of identifying place cells. By comparing these methods and quantifying the populations of place cells they identify, we aimed to increase our understanding of exactly the populations that are currently being studied under the name “place cells”. Although the appropriate method may depend on the experimental design, we generally recommend a single method going forward, which will increase consensus within the field about what should be included in a place cell population, and allow us to better compare results between studies.
Sparse balance: excitatory-inhibitory networks with small bias currents and broadly distributed synaptic weights
Authors: Khajeh Ramin , Fumarola Francesco , Abbott LF
Published: February 2021

Cortical circuits generate excitatory currents that must be cancelled by strong inhibition to assure stability. The resulting excitatory-inhibitory (E-I) balance can generate spontaneous irregular activity but, in standard balanced E-I models, this requires that an extremely strong feedforward bias current be included along with the recurrent excitation and inhibition. The absence of experimental evidence for such large bias currents inspired us to examine an alternative regime that exhibits asynchronous activity without requiring unrealistically large feedforward input. In these networks, irregular spontaneous activity is supported by a continually changing sparse set of neurons. To support this activity, synaptic strengths must be drawn from high-variance distributions. Unlike standard balanced networks, these sparse balance networks exhibit robust nonlinear responses to uniform inputs and non-Gaussian statistics. In addition to simulations, we present a mean-field analysis to illustrate the properties of these networks.
Incomplete recruitment of protective T cells facilitatesTrypanosoma cruzipersistence in the mouse colon
Authors: Ward Alexander I. , Lewis Michael D. , Taylor Martin C. , Kelly John M.
Published: February 2021

Trypanosoma cruziis the etiological agent of Chagas disease. Following T cell mediated suppression of the acute phase infection, this intracellular eukaryotic pathogen persists in a limited sub-set of tissues at extremely low-levels. The reasons for this tissue-specific chronicity are not understood. Using a dual bioluminescent:fluorescent reporter strain, which allows experimental infections to be imaged at single-cell resolution, we have characterised the ‘hyper-local’ immunological microenvironment of rare parasitized cells in the mouse colon, a key site of persistence. We demonstrate that incomplete recruitment of T cells to infection foci permits the occurrence of repeated cycles of intracellular parasite replication and differentiation to motile trypomastigotes at a frequency sufficient to perpetuate chronic infections. The life-long persistence of parasites in this tissue site continues despite the presence, at a systemic level, of a highly effective T cell response. Overcoming this low-level dynamic host:parasite equilibrium represents a major challenge for vaccine development.
Marked differences in local bone remodeling in response to different marrow stimulation techniques in a large animal
Authors: Zlotnick H.M. , Locke R.C. , Stoeckl B.D. , Patel J.M. , Gupta S. , Browne K.D. , Koh J. , Carey J.L. , Mauck R.L.
Published: February 2021

Marrow stimulation, including subchondral drilling and microfracture, is the most commonly performed cartilage repair strategy, whereby the subchondral bone plate is perforated to release marrow-derived cells into a cartilage defect to initiate repair. Novel scaffolds and therapeutics are being designed to enhance and extend the positive short-term outcomes of this marrow stimulation. However, the translation of these newer treatments is hindered by bony abnormalities, including bone resorption, intralesional osteophytes, and bone cysts, that can arise after marrow stimulation. In this study, three different marrow stimulation approaches — microfracture, subchondral drilling, and needle-puncture – were evaluated in a translationally relevant large animal model, the Yucatan minipig. The objective of this study was to determine which method of marrow access (malleted awl, drilled Kirschner wire, or spring-loaded needle) best preserved the underlying subchondral bone. Fluorochrome labels were injected at the time of surgery and 2 weeks post-surgery to capture bone remodeling over the first 4 weeks. Comprehensive outcome measures included cartilage indentation testing, histological grading, microcomputed tomography, and fluorochrome imaging. Our findings indicated that needle-puncture devices best preserved the underlying subchondral bone relative to other marrow access approaches. This may relate to the degree of bony compaction occurring with marrow access, as the Kirschner wire approach, which consolidated bone most, induced the most significant bone damage with marrow stimulation. This study provides basic science evidence in support of updated marrow stimulation techniques for preclinical and clinical practice.
Bortezomib inhibits lung fibrosis and fibroblast activation without proteasome inhibition
Authors: Penke Loka Raghu Kumar , Speth Jennifer , Wettlaufer Scott , Draijer Christina , Peters-Golden Marc
Published: February 2021

The FDA-approved proteasomal inhibitor bortezomib (BTZ) has attracted interest for its potential anti-fibrotic actions. However, neither itsin vivoefficacy in lung fibrosis nor its dependence on proteasome inhibition has been conclusively defined. Herein, we identify that therapeutic administration of BTZ in a mouse model of pulmonary fibrosis diminished the severity of fibrosis without reducing proteasome activity in the lung. Under conditions designed to mimic this lack of proteasome inhibitionin vitro, it reduced fibroblast proliferation, differentiation into myofibroblasts, and collagen synthesis. It promoted de-differentiation of myofibroblasts and overcame their characteristic resistance to apoptosis. Mechanistically, BTZ inhibited kinases important for fibroblast activation while inducing expression of dual-specificity phosphatase 1 or DUSP1, and knockdown of DUSP1 abolished its anti-fibrotic actions in fibroblasts. Our findings identify a novel proteasome-independent mechanism of anti-fibrotic actions for BTZ and support its therapeutic repurposing for pulmonary fibrosis.
Microglia become hypofunctional and release metalloproteases and tau seeds after phagocytosing live neurons with P301S tau aggregates
Authors: Brelstaff Jack H. , Mason Matthew , Katsinelos Taxiarchis , McEwan William A. , Ghetti Bernardino , Tolkovsky Aviva M. , Spillantini Maria Grazia
Published: February 2021

The microtubule-associated protein tau aggregates in multiple neurodegenerative diseases, causing inflammation and changing the inflammatory signature of microglia by unknown mechanisms. We have shown that microglia phagocytose live neurons containing tau aggregates cultured from P301S tau transgenic mice due to neuronal tau aggregate-induced exposure of the ‘eat me’ signal phosphatidylserine. Here we show that after phagocytosis, microglia become hypophagocytic while releasing seed-competent insoluble tau aggregates. These microglia activate acidic β-galactosidase, and release senescence-associated cytokines and matrix remodeling enzymes alongside tau, indicating a senescent phenotype. In particular, the marked NFκB-induced activation of matrix metalloprotease 3 (MMP3/stromelysinl) was replicated in the brains of P301S mutant tau transgenic mice, and in human brains from tauopathy patients. These data show that microglia that have been activated to ingest live neurons with tau aggregates behave hormetically, becoming hypofunctional while acting as vectors of tau aggregate spreading.
Asymmetric Contraction of Adherens Junctions arises through RhoA and E-cadherin feedback
Authors: Cavanaugh Kate E. , Staddon Michael , Chmiel Theresa A. , Harmon Robert , Budnar Srikanth , Yap Alpha S. , Banerjee Shiladitya , Gardel Margaret L.
Published: February 2021

Tissue morphogenesis often arises from the culmination of discrete changes in cell-cell junction behaviors, namely ratcheted junction contractions that lead to collective cellular rearrangements. Mechanochemical signaling in the form of RhoA underlies these ratcheted contractions, which occur asymmetrically as one highly motile vertex contracts toward a relatively less motile tricellular vertex. The underlying mechanisms driving asymmetric vertex movement remains unknown. Here, we use optogenetically controlled RhoA in model epithelia together with biophysical modeling to uncover the mechanism lending to asymmetric vertex motion. We find that both local and global RhoA activation leads to increases in junctional tension, thereby facilitating vertex motion. RhoA activation occurs in discrete regions along the junction and is skewed towards the less-motile vertex. At these less-motile vertices, E-cadherin acts as an opposing factor to limit vertex motion through increased frictional drag. Surprisingly, we uncover a feedback loop between RhoA and E-cadherin, as regional optogenetic activation of specified junctional zones pools E-cadherin to the location of RhoA activation. Incorporating this circuit into a mathematical model, we find that a positive feedback between RhoA-mediated tension and E-cadherin-induced frictional drag on tricellular vertices recapitulates experimental data. As such, the location of RhoA determines which vertex is under high tension, pooling E-cadherin and increasing the frictional load at the tricellular vertex to limit its motion. This feedback drives a tension-dependent intercellular “clutch” at tricellular vertices which stabilizes vertex motion upon tensional load.
Towards a two-stage model of action-stopping: Attentional capture explains motor inhibition during early stop-signal processing
Authors: Tatz Joshua R. , Soh Cheol , Wessel Jan R.
Published: February 2021

The ability to stop an already initiated action is paramount to adaptive behavior. Most scientific debate in the field of human action-stopping currently focuses on two interrelated questions. First: Which mental and neural processes underpin the implementation of inhibitory control, and which reflect the attentional detection of salient stop-signals instead? Second: Why do physiological signatures of inhibition occur at two different latencies after stop-signals (for visual signals, either before or after ∼150ms)? Here, we address both questions via two pre-registered experiments that combined transcranial magnetic stimulation, electromyography, and multi-variate pattern analysis of whole-scalp electroencephalography. Using a stop-signal task that also contained a second type of salient signal that did not require stopping, we found that both signals induced equal amounts of early-latency inhibitory activity, whereas only later signatures (after 175ms) distinguished the two. These findings resolve ongoing debates in the literature and strongly suggest a two-step model of action-stopping.
Podophyllotoxin and Quercetinin SilicoDerivatives Docking Analysis with Cyclooxygenase-2 and Aminopeptidase-N
Authors: Manukyan A.E. , Hovhannisyan A.A.
Published: February 2021

The cyclooxygenase (COX) enzymesaretumor markers, the inhibition of which can be used in the prevention and therapy of carcinogenesis. It was found that COX-2 IS considered as targets for tumor inhibition. Aminopeptidase N (APN) is a type II membrane-bound metalloprotease associated with cancer, being identified as a cell marker on the surface of malignant myeloid cells and reached a high level of expression in progressive tumors. In anticancer therapy, plant compounds are considered that can inhibit their activity. Modeling of the COX-2 and APN enzymes was carried out on the basis of molecular models of three-dimensional structures from the PDB database [PDB ID: 5f19, 4fyq] RCSB. For docking analysis, 3D ligand models were created using MarvinSketch based on the PubChem database [CID: 5280343, 5281654].In silicoexperiments, for the first time, revealed the possible interaction and inhibition of COX-2 and APN by quercetin and quercetin derivatives. Aspirin and Marimastat were taken to compare the results. Possible biological activities and possible side effects of the ligands have been identified.
On bridging paired-end RNA-seq data
Authors: Li Xiang , Shi Qian , Shao Mingfu
Published: February 2021

Motivation

The widely-used high-throughput RNA-sequencing technologies (RNA-seq) usually produce paired-end reads. We explore if full fragments can be computationally reconstructed from the sequenced two ends—a problem here we refer to asbridging. Solving this problem provides longer, more informative RNA-seq reads, and hence benefits downstream RNA-seq analysis such as transcriptome assembly and expression quantification. However, bridging is a challenging and complicated task owing to alternative splicing, transcript noises, and sequencing errors. It remains unclear if the data itself provides sufficient information for accurate bridging, let alone proper models and efficient algorithms that characterize and determine the true bridges.

Algorithmic Results

We studied this problem in two settings: reference-based bridging, which assumes reads alignments are available and reconstructs the alignments of full fragments, andde novobridging, which reconstructs sequences of entire fragments from sequences of the two ends. We proposed a novel mathematical formulation that works for both settings—to seek a path in an underlying graph data structure (i.e., splice graph for reference-based bridging, and compacted de Bruijn graph for de novo bridging) such that its bottleneck weight is maximized. This formulation characterizes true bridges and is efficient in filtering out false bridges. This formulation admits optimal substructure property, and hence efficient dynamic programming algorithms can be designed. For reference-based bridging, we designed such an algorithm to calculate the topNbridging paths, followed by a voting approach to select one using the distribution of fragment length. Forde novobridging, we designed a new truncated Dijkstra’s algorithm. To further speed up, we proposed a novel algorithm that reuses the shortest path tree to avoid running the truncated Dijkstra’s algorithm from scratch for all vertices. These innovations result in scalable algorithms that can bridge all paired-end reads in a compacted de Bruijn graph with millions of vertices.

Experimental Results

We showed that paired-end RNA-seq reads can be accurately bridged to a large extend. Our reference-based bridging tool could correctly bridge more than 79.6% of reads. Forde novobridging, high precision was observed with varied sensitivity. We also showed that bridging can improve reference-based transcript assembly: the improvement was significant (up to 14.4% measured with adjusted precision), and universal in all combinations with different aligners and assemblers.

Availability

Implementations of the algorithms for reference-based andde novobridging are available athttps://github.com/Shao-Group/rnabridge-alignandhttps://github.com/Shao-Group/rnabridge-denovo, respectively. Scripts, datasets, and documentations that can reproduce the experimental results in this manuscript are available athttps://github.com/Shao-Group/rnabridge-test.
Considerations on activity determinants of fungal polyphenol oxidases based on mutational and structural studies
Authors: Nikolaivits Efstratios , Valmas Alexandros , Dedes Grigorios , Topakas Evangelos , Dimarogona Maria
Published: February 2021

Polyphenol oxidases (PPOs) are an industrially relevant family of enzymes, being involved in the post-harvest browning of fruits and vegetables, as well as in human melanogenesis. Their involvement lies in their ability to oxidize phenolic or polyphenolic compounds, that subsequently form pigments. PPO family includes tyrosinases and catechol oxidases, which in spite of their high structural similarity, exhibit different catalytic activities. Long-standing research efforts have not yet managed to decipher the structural determinants responsible for this differentiation, as every new theory is disproved by a more recent study. In the present work, we combined biochemical along with structural data, in order to rationalize the function of a previously characterized PPO fromThermothelomyces thermophila(TtPPO). The crystal structure of aTtPPO variant, determined at 1.55 Å resolution, represents the second known structure of an ascomycete PPO. Kinetic data of structure-guided mutants prove the implication of “gate” residue L306, residue HB1+1 (G292) and HB2+1 (Y296) inTtPPO function against various substrates. Our findings demonstrate the role of L306 in the accommodation of bulky substrates and that residue HB1+1 is unlikely to determine monophenolase activity as suggested from previous studies.

IMPORTANCE

PPOs are enzymes of biotechnological interest. They have been extensively studied both biochemically and structurally, with a special focus on the plant-derived counterparts. Even so, explicit description of the molecular determinants of their substrate specificity is still pending. Especially for ascomycete PPOs, only one crystal structure has been determined so far, thus limiting our knowledge on this tree branch of the family. In the present study, we report the second crystal structure of an ascomycete PPO. Combined with site-directed mutagenesis and biochemical studies, we depict the amino acids in the vicinity of the active site that affect enzyme activity, and perform a detailed analysis on a variety of substrates. Our findings improve current understanding of structure-function relations of microbial PPOs, which is a prerequisite for the engineering of biocatalysts of desired properties.
Bioptim, a Python framework for Musculoskeletal Optimal Control in Biomechanics
Authors: Michaud Benjamin , Bailly François , Charbonneau Eve , Ceglia Amedeo , Sanchez Léa , Begon Mickael
Published: February 2021

Musculoskeletal simulations are useful in biomechanics to investigate the causes of movement disorder, to estimate non-measurable physiological quantities or to study the optimality of human movement. We introduceBioptim, an easy-to-use Python framework for biomechanical optimal control, handling musculoskeletal models. Relying on algorithmic differentiation and the multiple shooting formulation,Bioptiminterfaces nonlinear solvers to quickly provide dynamically consistent optimal solutions. The software is both computationally efficient (C++ core) and easily customizable, thanks to its Python interface. It allows to quickly define a variety of biomechanical problems such as motion tracking/prediction, muscle-driven simulations, parameters optimization, multiphase problems, etc. It is also intended for real-time applications such as moving horizon estimation and model predictive control. Six contrasting examples are presented, comprising various models, dynamics, objective functions and constraints. They include data-driven simulations (i.e., a multiphase muscle driven gait cycle and an upper-limb real-time moving horizon estimation of muscle forces) and predictive simulations (i.e., a muscle-driven pointing task, a twisting somersault with a quaternion-based model, a position controller using external forces, and a multiphase torque-driven maximum-height jump motion).
Bioorthogonal labeling of transmembrane proteins with non-canonical amino acids allows access to masked epitopes in live neurons
Authors: Bessa-Neto Diogo , Kuhlemann Alexander , Beliu Gerti , Pecoraro Valeria , Doose Sören , Retailleau Natacha , Chevrier Nicolas , Perrais David , Sauer Markus , Choquet Daniel
Published: February 2021

Progress in biological imaging is intrinsically linked to advances in labeling methods. The explosion in the development of high-resolution and super-resolution imaging calls for new approaches to label targets with small probes. These should allow to faithfully report the localization of the target within the imaging resolution – typically nowadays a few nanometers - and allow access to any epitope of the target, in the native cellular and tissue environment. We report here the development of a complete labeling and imaging pipeline using genetic code expansion and non-canonical amino acids in primary neurons that allows to fluorescently label masked epitopes in target transmembrane proteins in live neurons, both in dissociated culture and organotypic brain slices. This allowed us to image the differential localization of two glutamate receptor auxiliary proteins in complex with their partner with a variety of methods including widefield, confocal, anddSTORM super-resolution microscopy.
Ethnography of the socio-sanitary reception in Rome. How are HIV/AIDS and hepatitis b involved in creating the construction of legal categories assigned to migrants?
Authors: Santilli Cecilia
Published: February 2021

Purpose

This paper aims to investigate the role that Italian third sector organizations have in the process of social and administrative categorization of newly arrived migrants living with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/Aids) or hepatitis b. In Italy, free access to health is provided to all migrants and residence permits for medical treatment is granted for migrants living with a “serious illness” since the 1990s. The case of HIV/Aids and hepatitis b shows how this political openness, however, clashes with the tightening of migration policies.

Design/methodology/approach

The study is based on ethnographic research conducted between 2014 and 2016 within an associative centre that deals with the socio-health care of newly arrived migrants in Rome. In addition to the participant observations, the study is based in semi-structured interviews conducted with 10 health-care providers (nurses, health-care assistants and socio-cultural mediators) and doctors and with 22 migrants coming from Sub-Saharan Africa and living with HIV/AIDS (10) and hepatitis b (12).

Findings

In Italy, the two infections have been identified as top diseases among migrant populations in the country but if HIV/Aids is always considered as a “serious illness”, hepatitis b is considered as a public health priority only in the case of a treatment prescription. These aspects have an important impact on the interactions between medical and social professionals and migrants affected by HIV/AIDS and hepatitis b, contributing differently to the creation of legal categories assigned to migrants.

Originality/value

The case of HIV/Aids and hepatitis b shows how the political openness of the public health system, clashes with the tightening of migration policies and analyse the role of the third sector has in this issue.
A bibliometric analysis of the International Journal of Islamic and Middle Eastern Finance and Management
Authors: Özdemir Mücahit , Selçuk Mervan
Published: February 2021

Purpose

The purpose of this paper is to indicate the current state of studies on Islamic finance and management through a bibliometric analysis of the only social science citation index (SSCI)-indexed journal in this field.

Design/methodology/approach

The paper uses a bibliometric analysis, collecting data from the 319 papers published in the International Journal of Islamic and Middle Eastern Finance and Management (IMEFM) from 2008 to 2019. Moreover, VOSviewer software has been used to illustrate the citation analysis (including most cited papers, most cited authors and authors’ affiliated institutions and countries) and the keyword map.

Findings

The number of papers published in each issue of the IMEFM is found to have significantly increased owing to its unique situation being the only SSCI-indexed journal in this domain. The share of the empirical researches in total papers published annually has steadily risen, reaching 95% in 2019. In terms of case countries, although Malaysia is the most examined country in the papers, other countries such as Indonesia and Turkey are found to have been used as a case country by researchers recently. Islamic banking-related papers are the most prevalent studies, as expected, with mainly their performance being examined. Meanwhile, the number of papers about Islamic social financial institutions has notably grown in recent years. Finally, technology-based initiatives such as crowdfunding and cryptocurrencies are noted to have not yet been the subject of any paper.

Originality/value

The main contribution of this study is its analysis of the only SSCI-indexed journal on Islamic finance and management using bibliometrics. Also, all the papers published in the journal have been reviewed in terms of methodology, case country/country groups and topics/subtopics to lead the way for future research.
Investigating the effects of consistent visual identity on social media
Authors: Kaur Harsandaldeep , Kaur Kanwal Roop
Published: February 2021

Purpose

Although the prominence of social media for companies is widely acknowledged, a close examination of the literature reveals a lack of empirical research pertaining to the effect of consistency specifically on social media. Therefore, the purpose of this paper is to fill the gap in social media communication concerning the effect of consistent visual identity on social media users.

Design/methodology/approach

The study executed an experiment 2 (corporate visual identity condition) × 2 (organization type) between subjects design to map the effects of consistent visual identity on social media users appreciation of the visual identity, attitude toward the company, reputation and intention to commit to a company on social media.

Findings

The results of the study indicated the significant effects of consistent visual identity on social media users over the inconsistent conditions of visual identity on all dependent variables. Furthermore, there were insignificant main effects of organization type on general judgment, credibility, distinctiveness and reputation of the company.

Practical implications

This study presents the effects of consistent visual identity on social media platforms. The research will help marketing academicians, graphic designers and social media practitioners in online marketing by using its practical implications to strategically positioning their corporate brand in a social media environment.

Originality/value

This study provides novel insights on the impact of consistency on social media users. This is the first study to determine the role of consistent visual identity in the social media environment. It thereby adds to the literature of visual identity by developing the sphere of influence of consistency and its effects toward the user’s attitude.
Explaining the comparative perception of e-payment: role of e-shopping value, e-payment benefits and Islamic compliance
Authors: Garrouch Karim F.
Published: February 2021

Purpose

This study aims to examine three factors affecting the comparative e-payment perception, namely, perceived e-shopping value, e-payment benefits and Islamic Sharia compliance. It verifies an original model explaining the comparative perception of e-payment as a tool to pay online purchases. The newly integrated variables are the perceived compliance of the e-payment with Islamic Sharia, as a moderator, and the perceived e-shopping value, as a predictor. This investigation also tested the mediating role of e-payment benefits between perceived e-shopping value and e-payment comparative perception.

Design/methodology/approach

A questionnaire was distributed, via an online survey, to professional and personal networks of Master students who have spread the survey link to their social media groups. This procedure resulted in 185 valid observations.

Findings

Results show that the comparative perception of e-payment systems, as opposed to cash on delivery, is explained directly by e-payment benefits and indirectly by e-shopping value. The comparison of the model paths based on the perceived compliance to Islamic Sharia showed that this variable is non-significant as a moderator.

Originality/value

The verified model and paths of this study have not been covered yet, namely, the direct and indirect effects of e-shopping value. Thus, their verification constitutes the main originality of this article. Besides, the verification of the moderating role of compliance to Islamic sharia has not been verified in prior studies about e-payment.
Confiscation of proceeds of crime in Vietnam: improving the legal framework
Authors: Tran Thu Thi Hoai , De Koker Louis
Published: February 2021

Purpose

The purpose of this paper is to analyze the Vietnamese laws and practices concerning the confiscation of proceeds of crime, especially in view of Vietnam’s obligations to meet the international standards on money laundering and terrorist financing, set by the Financial Action Task Force and relevant international conventions that Vietnam ratified. To limit the scope of this paper, the analysis focuses on the confiscation of proceeds of domestic crimes that do not require international legal assistance. This paper concludes with recommendations for improving the legal framework on criminal asset recovery in Vietnam.

Design/methodology/approach

This is a doctrinal study that considers the applicable legal framework. This study is supported by brief case studies of major cases involving the confiscation of proceeds of crime.

Findings

Vietnam has a functioning asset confiscation regime but gaps in the law, lack of financial investigation expertise and lack of focused investigative attention on asset preservation and confiscation are hampering its effectiveness. The key gaps can easily be closed with appropriate amendments to the law. These reforms should be combined with a dedicated skills development program to produce sufficient number of financial investigation experts and criminal asset management experts to support the regime. The training should extend to judicial officers to ensure an appropriate understanding of the asset confiscation law. Reforms such as these should follow on a comprehensive review of Vietnam’s law and practices relating to the confiscation and forfeiture of criminal assets. This review should extend to assets linked to the financing of terrorism and proliferation to ensure that Vietnam has a comprehensive regime to deal with criminal assets.

Research limitations/implications

This paper draws on publicly available information regarding the confiscation of proceeds of crime in Vietnam. Little data is available on asset confiscation and that prevents an in-depth assessment of the regime.

Originality/value

This paper highlights gaps in the current asset confiscation regime and proposes reforms and approaches that will ensure a more effective asset confiscation regime for Vietnam.
Novel solitary wave solution of the nonlinear fractal Schrödinger equation and its fractal variational principle
Authors: Khan Yasir
Published: February 2021

Purpose

The nonlinear Schrödinger equation plays a vital role in wave mechanics and nonlinear optics. The purpose of this paper is the fractal paradigm of the nonlinear Schrödinger equation for the calculation of novel solitary solutions through the variational principle.

Design/methodology/approach

Appropriate traveling wave transform is used to convert a partial differential equation into a dimensionless nonlinear ordinary differential equation that is handled by a semi-inverse variational technique.

Findings

This paper sets out the Schrödinger equation fractal model and its variational principle. The results of the solitary solutions have shown that the proposed approach is very accurate and effective and is almost suitable for use in such problems.

Practical implications

Nonlinear Schrödinger equation is an important application of a variety of various situations in nonlinear science and physics, such as photonics, the theory of superfluidity, quantum gravity, quantum mechanics, plasma physics, neutron diffraction, nonlinear optics, fiber-optic communication, capillary fluids, Bose–Einstein condensation, magma transport and open quantum systems.

Originality/value

The variational principle of the Schrödinger equation without the Lagrange multiplier method in the sense of the fractal calculus is developed for the first time in the literature to the best of the author's understanding.
How corporate social responsibility mediates the relationship between corporate governance and sustainability performance in UK: a multiple mediator analysis
Authors: Maali Kachouri , Rakia Riguen , Khaireddine Mouakhar
Published: February 2021

Purpose

The purpose of this paper is to investigate the direct and indirect links between corporate governance and sustainability performance using corporate social responsibility.

Design/methodology/approach

The study is based on a sample consisting of 300 UK firms over the 2005–2017 period. This study applied structural equations models that specify both a direct and an indirect link between corporate governance and sustainability performance.

Findings

The authors find that corporate governance has a positive effect on sustainability performance. In addition, this study shows that corporate social responsibility fully mediates the relationship between corporate governance and sustainability performance in UK firms.

Practical implications

This study shows that firms are invited to engage more in sustainability performance and corporate social responsibility activities, which reduces agency conflicts between managers and shareholders.

Originality/value

To the authors’ knowledge, no research studies examined empirically the direct and indirect relationship between corporate governance and sustainability performance. Therefore, the main contribution of this research is to show how corporate governance effectiveness leads to higher corporate social responsibility level and sustainability performance using two analyses methods (mediator analysis and multiple mediator analysis).
Investor protection, corporate governance and private information-based trading
Authors: Lye Chun-Teck , Hooy Chee-Wooi
Published: February 2021

Purpose

This study aims to examine the effects of investor protection (PROT), internal and external corporate governance (CG) on private information-based trading (PIBT).

Design/methodology/approach

This study uses a sample of 3,438 firms from 42 countries for the period 2002–2015 to examine the effects of the broad and specific measures of PROT, internal CG and external CG (product market competition and block ownership [BOWN]) on a more accurate measure of PIBT using regression analysis.

Findings

The results show that PROT and BOWN are effective in reducing PIBT. However, the specific measure of PROT (strength of PROT) is not significant in emerging markets and civil law countries. The internal CG is also significant but has a positive effect on PIBT.

Research limitations/implications

The results suggest that PROT law matters in the efforts to prevent PIBT. Policymakers and securities market regulators, particularly in emerging markets and civil law countries, should focus more on refining existing securities laws and enacting detailed securities rules that explicitly prevent specific market manipulation and PIBT.

Originality/value

This study provides evidence for the importance of specific and detailed securities rules in different market and legal environments. Furthermore, this study uses the segregated private information-based speculative trading component to accurately measure the PIBT.
Role of aging temperature on thermomechanical fatigue lifetime of solder joints in electronic systems
Authors: Siswanto Waluyo Adi , Borodin Kirill , Mahmoud Zaid Hamid , Surendar A. , Sajjadifar Sami , Abdilova Galiya , Chang Jun
Published: February 2021

Purpose

The purpose of this study is to investigate the effect of aging temperature on the barrel-type solder joint lifetime of electronic devices and to include these effects in the modified prediction model.

Design/methodology/approach

Several accelerated shear stress tests under different stress amplitudes and aging temperatures were performed.

Findings

It was found that by aging temperature increasing, the lifetime decreases. Morrow energy model was also found as the best prediction model when the aging temperature is taken into consideration.

Originality value

It is confirmed.
Differential resistance and acclimation of two coral species to chronic nutrient enrichment reflect life‐history traits
Authors: Fox Michael D. , Nelson Craig E. , Oliver Thomas A. , Quinlan Zachary A. , Remple Kristina , Glanz Jess , Smith Jennifer E. , Putnam Hollie M.
Published: February 2021

The effects of nutrient pollution on coral reef ecosystems are multifaceted. Numerous experiments have sought to identify the physiological effects of nutrient enrichment on reef‐building corals, but the results have been variable and sensitive to choices of nutrient quantity, chemical composition and exposure duration.

To test the effects of chronic, ecologically relevant nutrient enrichment on coral growth and photophysiology, we conducted a 5‐week continuous dosing experiment on two Hawaiian coral species, Porites compressa and Pocillopora acuta. We acclimated coral fragments to five nutrient concentrations (0.1–7 µM and 0.06–2.24 µM ) with constant stoichiometry 2.5:1 nitrate to phosphate) bracketing in situ observations from reefs throughout the Pacific.

Nutrient enrichment linearly increased photophysiological performance of both species within 3 weeks. The effect of nutrients on P. acuta photochemical efficiency increased through time while a consistent response in P. compressa indicated acclimation to elevated nutrients within 5 weeks. Endosymbiont densities and total chlorophyll concentrations also increased proportionally with nutrient enrichment in P. acuta, but not in P. compressa, revealing contrasting patterns of host–symbiont acclimatization.

The two species also exhibited contrasting effects of nutrient enrichment on skeletal growth. Calcification was enhanced at low nutrient enrichment (1 µM ) in P. acuta, but comparable to the control at higher concentrations, whereas calcification was reduced in P. compressa (30%–35%) above 3 µM .

Stable isotope analysis revealed species‐specific nitrogen uptake dynamics in the coral–algal symbiosis. The endosymbionts of P. acuta exhibited increased nitrogen uptake (decreased δ15N) and incorporation (19%–31% decrease in C:N ratios) across treatments. In contrast, P. compressa endosymbionts maintained constant δ15N values and low levels of nitrogen incorporation (9%–11% decrease in C:N ratios). The inability of P. acuta to regulate endosymbiont nutrient uptake may indicate an emerging destabilization in the coral–algal symbiosis under nutrient enrichment that could compromise resistance to additional environmental stressors.

Our results highlight species‐specific differences in the coral–algal symbiosis, which influence responses to chronic nutrient enrichment. These findings showcase how symbioses can vary among closely related taxa and underscore the importance of considering how life‐history traits modify species response to environmental change.

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