bluuebunny/crossref_metadata_2025 huggingface dataset:
Poor Correlation between Diaphragm Thickening Fraction and Transdiaphragmatic Pressure in Mechanically Ventilated Patients and Healthy Subjects
Authors: Poulard Thomas , Bachasson Damien , Fossé Quentin , Niérat Marie-Cécile , Hogrel Jean-Yves , Demoule Alexandre , Gennisson Jean-Luc , Dres Martin
Published: November 2021

Background

The relationship between the diaphragm thickening fraction and the transdiaphragmatic pressure, the reference method to evaluate the diaphragm function, has not been clearly established. This study investigated the global and intraindividual relationship between the thickening fraction of the diaphragm and the transdiaphragmatic pressure. The authors hypothesized that the diaphragm thickening fraction would be positively and significantly correlated to the transdiaphragmatic pressure, in both healthy participants and ventilated patients.

Methods

Fourteen healthy individuals and 25 mechanically ventilated patients (enrolled in two previous physiologic investigations) participated in the current study. The zone of apposition of the right hemidiaphragm was imaged simultaneously to transdiaphragmatic pressure recording within different breathing conditions, i.e., external inspiratory threshold loading in healthy individuals and various pressure support settings in patients. A blinded offline breath-by-breath analysis synchronously computed the changes in transdiaphragmatic pressure, the diaphragm pressure-time product, and diaphragm thickening fraction. Global and intraindividual relationships between variables were assessed.

Results

In healthy subjects, both changes in transdiaphragmatic pressure and diaphragm pressure-time product were moderately correlated to diaphragm thickening fraction (repeated measures correlation = 0.40, P < 0.0001; and repeated measures correlation = 0.38, P < 0.0001, respectively). In mechanically ventilated patients, changes in transdiaphragmatic pressure and thickening fraction were weakly correlated (repeated measures correlation = 0.11, P = 0.008), while diaphragm pressure-time product and thickening fraction were not (repeated measures correlation = 0.04, P = 0.396). Individually, changes in transdiaphragmatic pressure and thickening fraction were significantly correlated in 8 of 14 healthy subjects (ρ = 0.30 to 0.85, all P < 0.05) and in 2 of 25 mechanically ventilated patients (ρ = 0.47 to 0.64, all P < 0.05). Diaphragm pressure-time product and thickening fraction correlated in 8 of 14 healthy subjects (ρ = 0.41 to 0.82, all P < 0.02) and in 2 of 25 mechanically ventilated patients (ρ = 0.63 to 0.66, all P < 0.01).

Conclusions

Overall, diaphragm function as assessed with transdiaphragmatic pressure was weakly related to diaphragm thickening fraction. The diaphragm thickening fraction should not be used in healthy subjects or ventilated patients when changes in diaphragm function are evaluated.

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Surgical Outcomes of Transposition Surgery for the Correction of Large-Angle Strabismus
Authors: Gokoffski Kimberly Kinga , Lifton Jacob , Xu Benjamin Yixing , Patel Vivek Ravindra
Published: November 2021

Background:

Many potential surgical options exist to address large-angle deviations and head turns that result from various forms of paralytic strabismus. Muscle transposition surgeries serve as suitable alternatives to simple resection–recessions. Here, we report outcomes of augmented Hummelsheim and X-type transpositions for the correction of large-angle strabismus and provide insights for surgical planning.

Methods:

We performed a retrospective chart review of 40 consecutive patients with strabismus who were treated with an augmented Hummelsheim or X-type transposition surgery at a single academic medical center. Etiologies included cranial nerve palsies (n = 26), monocular elevation palsy (n = 3), Duane syndrome (n = 1), traumatic extraocular muscle damage (n = 8), and chronic progressive external ophthalmoplegia (n = 2). All patients were followed for a minimum of 2 months postsurgery. Logistic regression analyses were performed to assess for predictors of surgical outcome.

Results:

Forty consecutive patients were enrolled in our series. The median preoperative deviation was 46.5Δ (interquartile range [IQR] 35–70). The median postoperative deviation 2 months after surgery was 0.5Δ (IQR 0–9.5), which represented a significant improvement (P < 0.001). Thirty-three patients (82.5%) experienced an improvement in range and/or centration of binocular single vision (BSV). More patients who underwent an augmented Hummelsheim procedure and had a small overcorrection at postoperative day 3 had a favorable result on postoperative month 2 (79%) compared with those that were initially under-corrected (38%). Multiple logistic regressions found larger preoperative deviation (P < 0.005) and esotropia (P < 0.021) to be predictors of a less favorable surgical outcome (C-statistic = 0.83). Subgroup analysis revealed that less, favorable outcome after X-type transposition occurred most frequently in patients undergoing correction of an esodeviation.

Conclusion:

Augmented Hummelsheim transposition techniques offer effective treatment options for paralytic strabismus with esotropic deviations, whereas X-type transpositions are effective for exotropic deviations and deviations from severe inferior rectus damage. In addition to potentially providing a wider field of BSV, improved centration is often achieved.
Neuroradiologic Imaging of Neurologic and Neuro-Ophthalmic Complications of Coronavirus-19 Infection
Authors: Marsiglia Marcela , Chwalisz Bart K. , Maher Mary
Published: November 2021

Background:

To review the literature and provide a summary of COVID-19–related neurologic and neuro-ophthalmic complications.

Methods:

The currently available literature was reviewed on PubMed and Google Scholar using the following keywords for searches: CNS, Neuro-Ophthalmology, COVID-19, SARS-CoV-2, coronavirus, optic neuritis, pseudotumor cerebri, Acute Disseminated Encephalomyelitis, posterior reversible encephalopathy syndrome (PRES), meningitis, encephalitis, acute necrotizing hemorrhagic encephalopathy, and Guillain–Barré and Miller Fisher syndromes.

Results:

Neuroradiologic findings of neurologic and neuro-ophthalmologic complications in relationship to COVID-19 infection were reviewed. Afferent visual pathway–related disorders with relevant imaging manifestations included fundus nodules on MRI, papilledema and pseudotumor cerebri syndrome, optic neuritis, Acute Disseminated Encephalomyelitis, vascular injury with thromboembolism and infarct, leukoencephalopathy, gray matter hypoxic injury, hemorrhage, infectious meningitis/encephalitis, acute necrotizing hemorrhagic encephalopathy, and PRES. Efferent visual pathway–related complications with relevant imaging manifestations were also reviewed, including orbital abnormalities, cranial neuropathy, Guillain–Barré and Miller Fisher syndromes, and nystagmus and other eye movement abnormalities related to rhombencephalitis.

Conclusion:

COVID-19 can cause central and peripheral nervous system disease, including along both the afferent and efferent components of visual axis. Manifestations of disease and long-term sequela continue to be studied and described. Familiarity with the wide variety of neurologic, ophthalmic, and neuroradiologic presentations can promote prompt and appropriate treatment and continue building a framework to understand the underlying mechanism of disease.
Comparative radiographic analysis of three-dimensional innate mobility of the foot bones under axial loading of humans and African great apes
Authors: Negishi Takuo , Ito Kohta , Hosoda Koh , Nagura Takeo , Ota Tomohiko , Imanishi Nobuaki , Jinzaki Masahiro , Oishi Motoharu , Ogihara Naomichi
Published: November 2021

The human foot is considered to be morphologically adapted for habitual bipedal locomotion. However, how the mobility and mechanical interaction of the human foot with the ground under a weight-bearing condition differ from those of African great apes is not well understood. We compared three-dimensional (3D) bone kinematics of cadaver feet under axial loading of humans and African great apes using a biplanar X-ray fluoroscopy system. The calcaneus was everted and the talus and tibia were internally rotated in the human foot, but such coupling motion was much smaller in the feet of African great apes, possibly due to the difference in morphology of the foot bones and articular surfaces. This study also found that the changes in the length of the longitudinal arch were larger in the human foot than in the feet of chimpanzees and gorillas, indicating that the human foot is more deformable, possibly to allow storage and release of the elastic energy during locomotion. The coupling motion of the calcaneus and the tibia, and the larger capacity to be flattened due to axial loading observed in the human foot are possibly morphological adaptations for habitual bipedal locomotion that has evolved in the human lineage.
A convenient formulation of Sadowsky's model for elastic ribbons
Authors: Neukirch Sébastien , Audoly Basile
Published: November 2021

Elastic ribbons are elastic structures whose length-to-width and width-to-thickness aspect ratios are both large. Sadowsky proposed a one-dimensional model for ribbons featuring a nonlinear constitutive relation for bending and twisting: it brings in both rich behaviours and numerical difficulties. By discarding non-physical solutions to this constitutive relation, we show that it can be inverted; this simplifies the system of differential equations governing the equilibrium of ribbons. Based on the inverted form, we propose a natural regularization of the constitutive law that eases the treatment of singularities often encountered in ribbons. We illustrate the approach with the classical problem of the equilibrium of a Möbius ribbon, and compare our findings with the predictions of the Wunderlich model. Overall, our approach provides a simple method for simulating the statics and the dynamics of elastic ribbons.
Physically motivated models of polymer networks with dynamic cross-links: comparative study and future outlook
Authors: Hui Chung-Yuen , Cui Fan , Zehnder Alan , Vernerey Franck J.
Published: November 2021

Polymer networks consisting of a mixture of chemical and physical cross-links are known to exhibit complex time-dependent behaviour due to the kinetics of bond association and dissociation. In this article, we highlight and compare two recent physically based constitutive models that describe the nonlinear viscoelastic behaviour of such transient networks. These two models are developed independently by two groups of researchers using different mathematical formulations. Here, we show that this difference can be attributed to different viewpoints: Lagrangian versus Eulerian. We establish the equivalence of the two models under the special situation where chains obey Gaussian statistics and steady-state bond dynamics. We provide experimental data demonstrating that both models can accurately predict the time-dependent uniaxial behaviour of a poly(vinylalcohol) dual cross-link hydrogel. We review the advantages and disadvantages of both approaches in applications and close by discussing a list of open challenges and questions regarding the mathematical modelling of soft, viscoelastic networks.
Evolution towards increasing complexity through functional diversification in a protocell model of the RNA world
Authors: Roy Suvam , Sengupta Supratim
Published: November 2021

The encapsulation of genetic material inside compartments together with the creation and sustenance of functionally diverse internal components are likely to have been key steps in the formation of ‘live’, replicating protocells in an RNA world. Several experiments have shown that RNA encapsulated inside lipid vesicles can lead to vesicular growth and division through physical processes alone. Replication of RNA inside such vesicles can produce a large number of RNA strands. Yet, the impact of such replication processes on the emergence of the first ribozymes inside such protocells and on the subsequent evolution of the protocell population remains an open question. In this paper, we present a model for the evolution of protocells with functionally diverse ribozymes. Distinct ribozymes can be created with small probabilities during the error-prone RNA replication process via the rolling circle mechanism. We identify the conditions that can synergistically enhance the number of different ribozymes inside a protocell and allow functionally diverse protocells containing multiple ribozymes to dominate the population. Our work demonstrates the existence of an effective pathway towards increasing complexity of protocells that might have eventually led to the origin of life in an RNA world.
Consonance perception in congenital amusia: behavioral and brain responses to harmonicity and beating cues
Authors: Graves Jackson E. , Pralus Agathe , Fornoni Lesly , Oxenham Andrew J. , Tillmann Barbara , Caclin Anne
Published: November 2021

Congenital amusia is a neurodevelopmental disorder characterized by difficulties in the perception and production of music, including the perception of consonance and dissonance, or the judgment of certain combinations of pitches as more pleasant than others. Two perceptual cues for dissonance are inharmonicity (the lack of a common fundamental frequency between components) and beating (amplitude fluctuations produced by close, interacting frequency components). In the presence of inharmonicities or beats, amusics have previously been reported to be insensitive to inharmonicity, but to exhibit normal sensitivity to beats. In the present study, we measured adaptive discrimination thresholds in amusic participants and found elevated thresholds for both cues. We recorded EEG and measured the mismatch negativity (MMN) in evoked potentials to consonance and dissonance deviants in an oddball paradigm. The amplitude of the MMN response was similar overall for amusics and controls, but while control participants showed a stronger MMN to harmonicity cues than to beating cues, amusic participants showed a stronger MMN to beating cues than to harmonicity cues. These findings suggest that initial encoding of consonance cues may be intact in amusia despite impaired behavioral performance, but that the relative weight of non-spectral cues may be increased for amusic individuals.
A copula based topology preserving graph convolution network for clustering of single-cell RNA seq data
Authors: Lall Snehalika , Ray Sumanta , Bandyopadhyay Sanghamitra
Published: November 2021

Annotation of cells in single-cell clustering requires a homogeneous grouping of cell populations. There are various issues in single cell sequencing that effect homogeneous grouping (clustering) of cells, such as small amount of starting RNA, limited per-cell sequenced reads, cell-to-cell variability due to cell-cycle, cellular morphology, and variable reagent concentrations. Moreover, single cell data is susceptible to technical noise, which affects the quality of genes (or features) selected/extracted prior to clustering.

Here we introduce sc-CGconv (copula based graph convolution network for single cell clustering), a stepwise robust unsupervised feature extraction and clustering approach that formulates and aggregates cell–cell relationships using copula correlation (Ccor), followed by a graph convolution network based clustering approach. sc-CGconv formulates a cell-cell graph using Ccor that is learned by a graph-based artificial intelligence model, graph convolution network. The learned representation (low dimensional embedding) is utilized for cell clustering. sc-CGconv features the following advantages. a. sc-CGconv works with substantially smaller sample sizes to identify homogeneous clusters. b. sc-CGconv can model the expression co-variability of a large number of genes, thereby outperforming state-of-the-art gene selection/extraction methods for clustering. c. sc-CGconv preserves the cell-to-cell variability within the selected gene set by constructing a cell-cell graph through copula correlation measure. d. sc-CGconv provides a topology-preserving embedding of cells in low dimensional space.

The source code and usage information are available at https://github.com/Snehalikalall/CopulaGCNContact:sumanta.ray@cwi.nl
Contingency and selection in mitochondrial genome dynamics
Authors: Nunn Christopher J. , Goyal Sidhartha
Published: November 2021

Eukaryotic cells contain numerous copies of mitochondrial DNA (mtDNA), allowing for the coexistence of mutant and wild-type mtDNA in individual cells. The fate of mutant mtDNA depends on their relative replicative fitness within cells and the resulting cellular fitness within populations of cells. Yet the dynamics of the generation of mutant mtDNA and features that inform their fitness remain unaddressed. Here we utilize long read single-molecule sequencing to track mtDNA mutational trajectories in Saccharomyces cerevisiae. We show a previously unseen pattern that constrains subsequent excision events in mtDNA fragmentation. We also provide evidence for the generation of rare and contentious non-periodic mtDNA structures that lead to persistent diversity within individual cells. Finally, we show that measurements of relative fitness of mtDNA fit a phenomenological model that highlights important biophysical parameters governing mtDNA fitness. Altogether, our study provides techniques and insights into the dynamics of large structural changes in genomes that may be applicable in more complex organisms.
A booster dose of an inactivated SARS-CoV-2 vaccine increases neutralizing antibodies and T cells that recognize Delta and Omicron variants of concern
Authors: Schultz Bárbara M , Melo-González Felipe , Duarte Luisa F , Gálvez Nicolás MS , Pacheco Gaspar A , Soto Jorge A , Berríos-Rojas Roslye V , González Liliana A , Moreno-Tapia Daniela , Rivera-Pérez Daniela , Ríos Mariana , Vázquez Yaneisi , Hoppe-Elsholz Guillermo , Vallejos Omar P , Iturriaga Carolina , Urzua Marcela , Navarrete María S , Rojas Álvaro , Fasce Rodrigo , Fernández Jorge , Mora Judith , Ramírez Eugenio , Gaete-Argel Aracelly , Acevedo Mónica , Valiente-Echeverría Fernando , Soto-Rifo Ricardo , Weiskopf Daniela , Grifoni Alba , Sette Alessandro , Zeng Gang , Meng Weining ,   CoronaVac03CL Study Group, González-Aramundiz José V , González Pablo A , Abarca Katia , Kalergis Alexis M , Bueno Susan M
Published: November 2021

Background

CoronaVac®is an inactivated SARS-CoV-2 vaccine approved by the World Health Organization. Previous studies reported increased levels of neutralizing antibodies and specific T cells two- and four-weeks after two doses of CoronaVac®, but the levels of neutralizing antibodies are reduced at six to eight months after two doses. Here we report the effect of a booster dose of CoronaVac®on the anti-SARS-CoV-2 immune response generated against variants of concern (VOC) Delta and Omicron in adults participating in a phase 3 clinical trial in Chile.

Methods

Volunteers immunized with two doses of CoronaVac®in a four-week interval received a booster dose of the same vaccine between twenty-four and thirty weeks after the 2nd dose. Four weeks after the booster dose, neutralizing antibodies and T cell responses were measured. Neutralization capacities and T cell activation against VOC Delta and Omicron were detected at four weeks after the booster dose.

Findings

We observed a significant increase in neutralizing antibodies at four weeks after the booster dose. We also observed an increase in CD4+T cells numbers over time, reaching a peak at four weeks after the booster dose. Furthermore, neutralizing antibodies and SARS-CoV-2 specific T cells induced by the booster showed activity against VOC Delta and Omicron.

Interpretation

Our results show that a booster dose of CoronaVac®increases the anti-SARS-CoV-2 humoral and cellular immune responses in adults. Immunity induced by a booster dose of CoronaVac®is active against VOC, suggesting an effective protection.
A recurrent circuit links antagonistic cerebellar modules during associative motor learning
Authors: Ohmae Shogo , Ohmae Keiko , Heiney Shane , Subramanian Divya , Medina Javier
Published: November 2021

The neural architecture of the cerebellum is thought to be specialized for performing supervised learning: specific error-related climbing fiber inputs are used to teach sensorimotor associations to small ensembles of Purkinje cells located in functionally distinct modules that operate independently of each other in a purely feedforward manner. Here, we test whether the basic operation of the cerebellum complies with this basic architecture in mice that learned a simple sensorimotor association during eyeblink conditioning. By recording Purkinje cells in different modules and testing whether their responses rely on recurrent circuits, our results reveal three operational principles about the functional organization of the cerebellum that stand in stark contrast to the conventional view: (1) Antagonistic organization, (2) Recurrent network dynamics, and (3) Intermodular communication. We propose that the neural architecture of the cerebellum implements these three operational principles to achieve optimal performance and solve a number of problems in motor control.
The Nerve Growth Factor IB-like Receptor Nurr1 (NR4A2) Recruits CoREST Transcription Repressor Complexes to Silence HIV Following Proviral Reactivation in Microglial Cells
Authors: Ye Fengchun , Alvarez-Carbonell David , Nguyen Kien , Valadkhan Saba , Leskov Konstantin , Garcia-Mesa Yoelvis , Sreeram Sheetal , Karn Jonathan
Published: November 2021

Human immune deficiency virus (HIV) infection of microglial cells in the brain leads to chronic neuroinflammation, which is antecedent to the development of HIV-associated neurocognitive disorders (HAND) in the majority of patients. Productively HIV infected microglia release multiple neurotoxins including proinflammatory cytokines and HIV proteins such as envelope glycoprotein (gp120) and transactivator of transcription (Tat). However, powerful counteracting silencing mechanisms in microglial cells result in the rapid shutdown of HIV expression to limit neuronal damage. Here we investigated whether the Nerve Growth Factor IB-like nuclear receptor Nurr1 (NR4A2), which is a repressor of inflammation in the brain, acts to directly restrict HIV expression. HIV silencing was substantially enhanced by Nurr1 agonists in both immortalized human microglial cells (hµglia) and induced pluripotent stem cells (iPSC)-derived human microglial cells (iMG). Overexpression of Nurr1 led to viral suppression, whereas by contrast, knock down (KD) of endogenous Nurr1 blocked HIV silencing. Chromatin immunoprecipitation (ChIP) assays showed that Nurr1 mediates recruitment of the CoREST/HDAC1/G9a/EZH2 transcription repressor complex to HIV promoter resulting in epigenetic silencing of active HIV. Transcriptomic studies demonstrated that in addition to repressing HIV transcription, Nurr1 also downregulated numerous cellular genes involved in inflammation, cell cycle, and metabolism, thus promoting HIV latency and microglial homoeostasis. Thus, Nurr1 plays a pivotal role in modulating the cycles of proviral reactivation by cytokines and potentiating the proviral transcriptional shutdown. These data highlight the therapeutic potential of Nurr1 agonists for inducing HIV silencing and microglial homeostasis and amelioration of the neuroinflammation associated with HAND.

AUTHOR SUMMARY

HIV enters the brain almost immediately after infection where it infects perivascular macrophages, microglia and, to a less extent, astrocytes. In previous work using an immortalized human microglial cell model, we observed that integrated HIV constantly underwent cycles of reactivation and subsequent silencing. In the present study, we found that the Nurr1 nuclear receptor is a key mediator of HIV silencing. The functional activation of Nurr1 by specific agonists, or the over expression of Nurr1, resulted in rapid silencing of activated HIV in microglial cells. Global gene expression analysis confirmed that Nurr1 not only repressed HIV expression but also regulated numerous genes involved in microglial homeostasis and inflammation. Thus, Nurr1 is pivotal for HIV silencing and repression of inflammation in the brain and is a promising therapeutic target for treatment of HAND.
Binding stoichiometry and structural model of the HIV-1 Rev/Importin β complex
Authors: Spittler Didier , Indorato Rose-Laure , Erba Elisabetta Boeri , Delaforge Elise , Signor Luca , Harris Simon J. , Garcia-Saez Isabel , Palencia Andrés , Gabel Frank , Blackledge Martin , Noirclerc-Savoye Marjolaine , Petosa Carlo
Published: November 2021

HIV-1 Rev mediates the nuclear export of intron-containing viral RNA transcripts and is essential for viral replication. Rev is imported into the nucleus by the host protein Importin β (Impβ), but how Rev associates with Impβ is poorly understood. Here we report biochemical, biophysical and structural studies of the Impβ/Rev complex. Gel shift, native mass spectrometry and isothermal titration calorimetry data reveal that Impβ binds two Rev monomers through independent binding sites. Small-angle X-ray scattering (SAXS) data suggest that the HEAT repeats of Impβ retain an extended conformation upon binding Rev, which according to NMR data is primarily recognized through its helical hairpin domain. Peptide scanning data and charge-reversal mutations identify the N-terminal tip of Rev helix α2 within Rev’s Arginine-Rich Motif (ARM) as a primary Impβ binding epitope. Crosslinking mass spectrometry and compensatory mutagenesis data combined with molecular docking simulations suggest a structural model in which one Rev monomer binds to the C-terminal half of Impβ with Rev helix α2 roughly parallel to the HEAT-repeat superhelical axis while the other monomer binds to the N-terminal half. These findings shed light on the molecular basis of Rev recognition by Impβ and highlight an atypical binding behaviour that distinguishes Rev from canonical cellular Impβ cargos.
piCRISPR: Physically Informed Deep Learning Models for CRISPR/Cas9 Off-Target Cleavage Prediction
Authors: Störtz Florian , Mak Jeffrey , Minary Peter
Published: November 2021

CRISPR/Cas programmable nuclease systems have become ubiquitous in the field of gene editing. With progressing development, applications inin vivotherapeutic gene editing are increasingly within reach, yet limited by possible adverse side effects from unwanted edits. Recent years have thus seen continuous development of off-target prediction algorithms trained onin vitrocleavage assay data gained from immortalised cell lines. It has been shown that in contrast to experimental epigenetic features, computed physically informed features are so far underutilised despite bearing considerably larger correlation with cleavage activity. Here, we implement state-of-the-art deep learning algorithms and feature encodings for off-target prediction with emphasis onphysically informedfeatures that capture the biological environment of the cleavage site, hence terming our approach piCRISPR. Features were gained from the large, diverse crisprSQL off-target cleavage dataset. We find that our best-performing models highlight the importance of sequence context and chromatin accessibility for cleavage prediction and compare favourably with literature standard prediction performance. We further show that our novel, environmentally sensitive features are crucial to accurate prediction on sequence-identical locus pairs, making them highly relevant for clinical guide design. The source code and trained models can be found ready to use at github.com/florianst/picrispr.
Structure of the rabies virus glycoprotein trimer bound to a pre-fusion specific neutralizing antibody
Authors: Callaway Heather M. , Zyla Dawid , Hastie Kathryn M. , Avalos Ruben Diaz , Agarwal Alyssa , Bourhy Hervé , Corti Davide , Saphire Erica Ollmann
Published: November 2021

Rabies infection is nearly 100% lethal if untreated and kills over 50,000 people annually, many of them children. Existing rabies vaccines target the rabies virus glycoprotein (RABV-G) but generate short-lived immune responses, likely because the protein is heterogeneous under physiological conditions. Here, we report the 3.39Å cryo-EM structure of trimeric, pre-fusion RABV-G complexed with RVA122, a potently neutralizing human antibody. RVA122 binds to a quaternary epitope at the top of RABV-G, bridging domains and stabilizing RABV-G protomers in a prefusion state. RABV-G trimerization involves side-to-side interactions between the central α-helix and adjacent loops, rather than contacts between central helices, and interactions among the fusion loops at the glycoprotein base. These results provide a basis to develop improved rabies vaccines based on RABV-G stabilized in the prefusion conformation.

One sentence summary

We report the structure and trimeric interface of pre-fusion rabies virus glycoprotein bound to the neutralizing antibody RVA122.
Floor plate-derived neuropilin-2 functions as a secreted semaphorin sink to facilitate commissural axon midline crossing
Authors: Hernandez-Enriquez Berenice , Wu Zhuhao , Martinez Edward , Olsen Olav , Kaprielian Zaven , Maness Patricia F. , Yoshida Yutaka , Tessier-Lavigne Marc , Tran Tracy S.
Published: November 2021

Commissural axon guidance depends on a myriad of cues expressed by intermediate targets. Secreted semaphorins signal through neuropilin-2/plexin-A1 receptor complexes on post-crossing commissural axons to mediate floor plate repulsion in the mouse spinal cord. Here, we show that neuropilin-2/plexin-A1 are also coexpressed on commissural axons prior to midline crossing and can mediate precrossing semaphorin-induced repulsion in vitro. How premature semaphorin-induced repulsion of precrossing axons is suppressed in vivo is not known. We discovered that a novel source of floor plate-derived, but not axon-derived, neuropilin-2 is required for precrossing axon pathfinding. Floor plate-specific deletion of neuropilin-2 significantly reduces the presence of precrossing axons in the ventral spinal cord, which can be rescued by inhibiting plexin-A1 signaling in vivo. Our results show that floor plate-derived neuropilin-2 is developmentally regulated, functioning as a molecular sink to sequester semaphorins, preventing premature repulsion of precrossing axons prior to subsequent down-regulation, and allowing for semaphorin-mediated repulsion of post-crossing axons.
Transient myeloproliferative disorder as the presenting feature for mosaic trisomy 21
Authors: Baca Nicole , Sanchez-Lara Pedro A. , Schreck Rhona , Eno Celeste C. , Majlessipour Fataneh
Published: November 2021

Trisomy 21 is a common congenital disorder with well-documented clinical manifestations, including an increased risk for the transient myeloproliferative disorder as a neonate and leukemia in childhood and adolescence. Transient myeloproliferative disorder is only known to occur in hematopoietic cells with trisomy 21. Children with mosaic trisomy 21 also have a risk for hematological malignancies. We present a nondysmorphic neonate, with a negative noninvasive prenatal screening of maternal blood for trisomy 21, who came to medical attention because of ruddy skin. He was found to have mild polycythemia, thrombocytopenia, and developed peripheral blasts. His clinical presentation was consistent with transient myeloproliferative disorder, which is only seen with trisomy 21. Cytogenetic studies of peripheral blood are positive for mosaic trisomy 21.
Experiences of information literacy and mobile technologies amongst undergraduates in times of COVID. A qualitative approach
Authors: Pinto Maria , Caballero Mariscal David , Segura Alicia
Published: November 2021

Purpose

The purpose of this article is to analyse the social science students' perceptions of information literacy (IL) and the use of mobile technologies (MTs) before and during the COVID-19 pandemic.

Design/methodology/approach

Exploratory focus group methodology involving 18 Information Science and Education undergraduates.

Findings

Students believe that, above all, an information literate person must know how to search for information. Being able to recognise acceptable levels of IL and MT competencies/skills enabled them to detect the scant contribution of the university to IL and the poor support from the library. They routinely use information and communication technologies (ICTs) in the classroom for assignments, presentations, searching and administrative tasks. Conversely, they consider their teachers' competency in the use of mobile devices for academic tasks could be improved. The increase in these shortcomings during the COVID-19 pandemic has allowed students to discover most teachers' attitudinal and technical limitations. Students' suggestions mostly point to improving platforms, teaching methods, teacher motivation and teachers/librarians interaction.

Research limitations/implications

Research is limited to several IL/MT-related concepts, one university and two degrees. It could be applied in other contexts, larger samples and other stakeholders such as librarians and teachers.

Practical implications

Need for more IL and TM instruction for students/teachers and greater interaction amongst them and with the library. The authors suggest promoting interdisciplinary seminars on the importance of IL and awareness sessions on ICT for learning.

Originality/value

This case study addresses students' critical/exceptional experience triggered by the pandemic.
Comparative assessments of strain measures for nonlinear analysis of truss structures at large deformations
Authors: Greco Marcelo , Peixoto Daniel Henrique Nunes
Published: November 2021

Purpose

In this paper the use of classical strain measures in analysis of trusses at finite deformations will be discussed. The results will be compared to the ones acquired using a novel strain measure based on the Hyperbolic Sine function. Through the evaluation of results, algebraic development and graph analysis, the properties of the Hyperbolic Sine strain measure will be examined.

Design/methodology/approach

Through graph plotting, comparisons between the novel strain measure and the classic ones will be made. The formulae for the implementation of the Hyperbolic Sine strain measure into a positional finite element method are developed. Four engineering applications are presented and comparisons between results obtained using all strain measures studied are made.

Findings

The proposed strain measure, Hyperbolic Sine, has objectivity and symmetry. The linear constitutive model formed by the Hyperbolic Sine strain and its conjugated stress presents an increasing stiffness, both in compression and tension, a behavior that can be useful in the modeling of several materials.

Research limitations/implications

The structural analysis performed on the four examples of trusses in this article did not consider the variation of the cross-sectional area of the elements or the buckling phenomenon, moreover, only elastic behavior is considered.

Originality/value

The present article proposes the use of a novel strain measure family, based on the Hyperbolic Sine function and suitable for structural applications. Mathematical expressions for the use of the Hyperbolic Sine strain measure are established following the energetic concepts of the positional formulation of the finite element method.
The impact of gender inequality in education and employment on economic performance in Turkey: evidence from a cointegration approach
Authors: Esen Ömer , Seren Gamze Yıldız
Published: November 2021

Purpose

This study aims to empirically examine the impact of gender-based inequalities in both education and employment on economic performance using the dataset of Turkey for the period 1975–2018.

Design/methodology/approach

This study employs Johansen cointegration tests to analyze the existence of a long-term relation among variables. Furthermore, dynamic ordinary least squares (DOLS) and fully modified ordinary least squares (FMOLS) estimation methods are performed to determine the long-run coefficients.

Findings

The findings from the Johansen cointegration analysis confirm that there is a long-term cointegration relation between variables. Moreover, DOLS and FMOLS results reveal that improvements in gender equality in both education and employment have a strong and significant impact on real gross domestic product (GDP) per capita in the long term.

Originality/value

The authors expect that this study will make remarkable contributions to the future academic studies and policy implementation, as it examines the relation among the variables by including the school life expectancy from primary to tertiary based on the gender parity index (GPI), the gross enrollment ratio from primary to tertiary based on GPI and the ratio of female to male labor force participation (FMLFP) rate.
Assessing the performance of Islamic banks in Malaysia based on balanced scorecard (BSC) measures and Shari'ah guidelines compliance
Authors: Abueid Raed
Published: November 2021

Purpose

Islamic banking sector is gaining popularity globally. However, in recent decades, Malaysia's Islamic banking sector has been reckoned as an influential force in the global economy and became a rapidly growing industry. In fact, the international banking industry has admitted Malaysia as the leading Islamic banking center with the most progressive and attractive planning, strategic directions of development, and numerous incentives for nurturing this sector. Hence, this paper aims to evaluate the performance of Islamic banks in Malaysia based on Balanced Scorecard (BSC) measures and Shari'ah Guidelines Compliance.

Design/methodology/approach

To achieve the objectives of this paper, BSC performance evaluation system and Shari'ah Guidelines Compliance were used based on the data collected through an online poll survey across Malaysian Islamic banks from an aggregate of 994 information focused on 71 items, using 14 respondents in which ten were from the regional level and four were from the headquarters of the bank. Furthermore, nine respondents were bank managers and five were bank employees.

Findings

The findings of the paper are as follows: First, there is a useful connection among BSC estimates, attributes of Shari’ah Compliance and Islamic banks' performance. Second, tremendous improvement has been seen in the Malaysian Islamic banks, which used both the BSC measures and Shari'ah Guidelines Compliance.

Practical implications

The practical implication of the findings is that utilizing the BSC count and Shari’ah consistence characteristics; Islamic banks can better their exhibition and therefore, the banks ought to receive the recorded down rules alongside the BSC measures and Shari'ah ascribes to accomplish a superior presentation, benefit and achievement of Islamic currency advertise.

Originality/value

The novelty/originality of this paper can be seen from the fact that despite the BSC becoming a widely used performance management tool; still, there is a deficiency of standardization between a company and its perception of the term BSC and also mostly, research works on BSC were carried out on the United States- and European-based organizations, but in Malaysia, nothing more was done, especially in the Islamic banking sector, while this model is capable of covering both economic and non-economic estimate of presentation and therefore, considered as a sophisticated presentation computation system for performance evaluation.
Design of low power SRAM- based ubiquitous sensor for wireless body area networks
Authors: Neeraj Kumar , Mahaboob Basha Mohammed , Gundala Srinivasulu
Published: November 2021

Purpose

Smart ubiquitous sensors have been deployed in wireless body area networks to improve digital health-care services. As the requirement for computing power has drastically increased in recent years, the design of low power static RAM-based ubiquitous sensors is highly required for wireless body area networks. However, SRAM cells are increasingly susceptible to soft errors due to short supply voltage. The main purpose of this paper is to design a low power SRAM- based ubiquitous sensor for healthcare applications.

Design/methodology/approach

In this work, bias temperature instabilities are identified as significant issues in SRAM design. A level shifter circuit is proposed to get rid of soft errors and bias temperature instability problems.

Findings

Bias Temperature Instabilities are focused on in recent SRAM design for minimizing degradation. When compared to the existing SRAM design, the proposed FinFET-based SRAM obtains better results in terms of latency, power and static noise margin. Body area networks in biomedical applications demand low power ubiquitous sensors to improve battery life. The proposed low power SRAM-based ubiquitous sensors are found to be suitable for portable health-care devices.

Originality/value

In wireless body area networks, the design of low power SRAM-based ubiquitous sensors are highly essential. This design is power efficient and it overcomes the effect of bias temperature instability.
Reliability analysis of a small solar system for a home
Authors: Musa Ismail Muhammad , Yusuf Ibrahim
Published: November 2021

Purpose

The purpose of this paper is to model and to improve the stability and long-lasting operation of the small home solar system configuration regarding the reliability, availability, sensitivity, cost analysis and mean time to failure (MTTF).

Design/methodology/approach

A model of a small home solar system is designed in this write up. It is designed in a series–parallel configuration, such that four panels are arranged in parallel, working under 1-out-of-4: G; policy and two batteries configured in parallel also, working under 1-out-of-2: G; policy. The panels are connected to a charge controller, then to the batteries and lastly to an inverter, all connected together in series configuration. Different types of system reliability such as reliability, sensitivity, availability, MTTF and cost analysis for particular values of the failure and repair rates have been evaluated by using a supplementary variable and Laplace transforms and demonstrated the computed results on tables and graphs. The main objective here is to improve the stability and long-lasting operation of the small solar system configuration regarding the reliability, availability, sensitivity, cost analysis and MTTF.

Findings

The future behavior of the small solar system and similar systems can be easily predicted at any given time for any parametric values, it is also better to provide repair than replacements in the system for better availability and reliability, it signifies that γp, γb, γc and γi are responsible for the better performance of the system, the variation of sensitivity together with the parametric values variations and lastly deduced that the profit will decrease whenever service cost increase.

Originality/value

This paper provides a model of small home solar system and its reliability analysis.
Improving knowledge transfer through enterprise social media: the mediating role of transactive memory
Authors: Sun Yuan , Shang Rong-An , Cao Haiyang , Jiang Hongyu , Boehnke Klaus , Fu Jindi
Published: November 2021

Purpose

Enterprise social media can be the organizational transactive memory in which the knowledge dialogue provides users with the metaknowledge to support knowledge transfer. The purpose of this study is to examine a mediation model to show how perceived critical mass, openness and affiliation climate affect organizational knowledge transfer through the mediation of improving the metaknowledge of who knows what and whom.

Design/methodology/approach

To test the mediation model and corresponding hypotheses, this study employs structural equation modeling analysis using 264 valid questionnaires.

Findings

The study found the two mediators fully explained the effects of the three preconditions on knowledge transfer.

Originality/value

These results help us to better understand the benefits of enterprise social media and the functions of transactive memory in organizations.
Alternate remittance systems in Ghana: a trade enabler or an organised fraud
Authors: Asmah Alexander , Atuilik Williams Abayaawien
Published: November 2021

Purpose

Alternate remittance systems (ARS) are inherently not illegal; however, the nature of their activities has mostly been linked with money laundering and terrorist financing, which raises several questions as to why businesses in Ghana rely on these systems to conduct their cross-border trade. The purpose of this study is seeks to understand the nature of ARS in Ghana and analyse why business owners rely on them for their transactions.

Design/methodology/approach

Three companies were selected for the case study analysis. This research paper used a qualitative data analysis for the study. Interviews, direct participant observation and documentary review were the main techniques for data collection. The multiple sources of evidence helped to reduce the potential bias of the single method.

Findings

This paper found that some businesses using the system in Ghana can acquire unsecured loans at little or no interest cost, which provides a good source of funding to support business growth. Unlike other studies, this study proves that in some instances, ARS operators transact business with the clients they do not, particularly trust. Within the context of this study, this paper found evidence that supports money laundering, but the underlining crime is mostly tax evasion. The adoption of the system is an attempt to disguise the proceeds of the tax evasion crime and clean them through business operations.

Research limitations/implications

This analysis was based on the strain theory from the perspective of the clients. Future studies can focus attention on the ARS operators and understand their perspectives. Several other fraud theories could be used as a lens to understand the phenomena in Ghana and other jurisdictions.

Practical implications

The study throws more light on a “secret” or an underground banking system that operates in Ghana. It provides insights that can guide regulatory authorities in their policy implementation. The need for stricter enforcement of the law has also been highlighted.

Originality/value

To the best of the authors’ knowledge, this study is original, as it focuses on a sector that is highly secretive but has significant implications on the Ghanaian economy.
“Reporting the wrong to the right”: the mediated moderation model of whistleblowing education and the whistleblowing intentions
Authors: Aslam Muhammad Kashif , Akhtar Muhammad Saeed , Akhtar Muhammad Waheed , Asrar-ul-Haq Muhammad , Iqbal Jawad , Usman Muhammad
Published: November 2021

Purpose

The purpose of this paper is to elucidate the social information processing theory, which is extended by the (1) effect of whistleblowing education on whistleblowing intentions, (2) simultaneous examination of the indirect relationship between whistleblowing education and whistleblowing intentions via moral identity and (3) relativism in influencing this mediation.

Design/methodology/approach

Multi-wave data collected at three internals from bank employees (n = 294) were analyzed to test the proposed model.

Findings

Results of the study demonstrate that whistleblowing education favorably influences whistleblowing intentions directly as well as through moral identity. Relativism serves as the buffer in the indirect effects of whistleblowing education on whistleblowing intentions through moral identity attenuating these indirect effects in individuals with dominant relativism level.

Originality/value

This study strives to extend the whistleblowing education and whistleblowing intentions literature by unpacking a moral identity mechanism through which whistleblowing education kindles whistleblowing intention and relativism as boundary condition to attenuate such motivation.