bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving outcomes in acute and chronic periprosthetic hip and knee joint infection with a multidisciplinary approach
Authors: Biddle Mairiosa , Kennedy Ian W. , Wright Pauline M. , Ritchie Neil D. , Meek R. M. D. , Rooney Brian P.
Published: July 2021

Aims

Periprosthetic hip and knee infection remains one of the most severe complications following arthroplasty, with an incidence between 0.5% to 1%. This study compares the outcomes of revision surgery for periprosthetic joint infection (PJI) following hip and knee arthroplasty prior to and after implementation of a specialist PJI multidisciplinary team (MDT).

Methods

Data was retrospectively analyzed from a single centre. In all, 29 consecutive joints prior to the implementation of an infection MDT in November 2016 were compared with 29 consecutive joints subsequent to the MDT conception. All individuals who underwent a debridement antibiotics and implant retention (DAIR) procedure, a one-stage revision, or a two-stage revision for an acute or chronic PJI in this time period were included. The definition of successfully treated PJI was based on the Delphi international multidisciplinary consensus.

Results

There were no statistically significant differences in patient demographics or comorbidities between the groups. There was also no significant difference in length of overall hospital stay (p = 0.530). The time taken for formal microbiology advice was significantly shorter in the post MDT group (p = 0.0001). There was a significant difference in failure rates between the two groups (p = 0.001), with 12 individuals (41.38%) pre-MDT requiring further revision surgery compared with one individual (6.67%) post-MDT inception.

Conclusion

Our standardized multidisciplinary approach for periprosthetic knee and hip joint infection shows a significant reduction in failure rates following revision surgery. Following implementation of our MDT, our success rate in treating PJI is 96.55%, higher than what current literature suggests. We advocate the role of a specialist infection MDT in the management of patients with a PJI to allow an individualized patient-centred approach and care plan, thereby reducing postoperative complications and failure rates.

Cite this article: Bone Jt Open 2021;2(7):509–514.
An enhanced discrete Mindlin finite element model using a zigzag function
Authors: Sedira Lakhdar , Ayad Rezak , Sabhi Hamid , Hecini Mabrouk , Sakami Siham
Published: July 2021

The present work deals with the formulation and the evaluation of a discrete finite element model for Reissner/Mindlin composite plates, including the introduction of zigzag form in order to improve plane and shear stress accuracy. The model is characterised by a piecewise linear variation of displacement, which allows to fulfil the stress continuity requirements. For this purpose, a new four-node quadrilateral enhanced finite element based on a quadratic displacement field is proposed. In the second version, it incorporates two additional zigzag terms and does not require shear correction. The element is validated across some known problems in the literature, highlighting the improvement of thickness stress distributions, by comparison with the initial model without zigzag function.
A space fibre as added value in finite element modelling for optimal analysis of problems involving contact
Authors: Ghomari Tewfik , Meftah Kamel , Ayad Rezak , Talbi Nabil
Published: July 2021

The present work deals with the non-linear formulation of an axisymmetric hyperelastic solid model, based on the concept space fibre rotation (SFR). The SFR-Axi model uses the kinematics of a space fibre to obtain a quite accurate displacement field. It improves in a significant way the precision of the linear element Q4-Axi. It can even be compared, on the accuracy and CPU time level, with the high-order elements as Q8-Axi for instance. A hyperelastic law, based on the Mooney–Rivlin model, is implemented to allow to the present model a better simulation of the forming process of hollow plastic bodies. The numerical results relate to primarily some known tests of hyperelastic structures, with and without contact (swellings).
Material fatigue simulation using a periodic time-homogenisation method
Authors: Puel Guillaume , Aubry Denis
Published: July 2021

This paper deals with the numerical simulation of combined cycle fatigue, which is characterised by two periodic loads, whose frequencies are very different one from the other. Rather than using classical fatigue life estimations, a time transient evolution model is solved using a periodic time-homogenisation method. This latter is based on the assumption that the time scales associated with the two periodic loads are decoupled. Different results on academic as well as industrial examples are presented. An extension of the proposed method up to three time scales is eventually proposed in order to speed up the numerical simulations.
A first step toward a PGD-based time parallelisation strategy
Authors: Poulhaon Fabien , Chinesta Francisco , Leygue Adrien
Published: July 2021

This paper proposes a new method for solving the heat transfer equation based on a parallelisation in time of the computation. A parametric multidimensional model is solved within the context of the Proper Generalised Decomposition (PGD). The initial field of temperature and the boundary conditions of the problem are treated as extra-coordinates, similar to time and space. Two main approaches are exposed: a “full” parallelisation based on an off-line parallel computation and a “partial” parallelisation based on a decomposition of the original problem. Thanks to an optimised overlapping strategy, the reattachment of the local solutions at the interfaces of the time subdomains can be improved. For large problems, the parallel execution of the algorithm provides an interesting speedup and opens new perspectives regarding real-time simulation.
Multi-scale modelling of the trabecular bone elastoplastic behaviour under compression loading
Authors: Jaziri A. , Rahmoun J. , Naceur H. , Drazetic P. , Markiewicz E.
Published: July 2021

We propose a new elastoplastic damage coupled model for the modelling of trabecular bone behaviour. The damage is carried out thanks to the limit analysis based on the MCK criterion. We first present the methodology allowing the estimation of elastic anisotropic properties of porous media by means of Mori–Tanaka homogenisation scheme. Then, we present the formulation of the integrated yield criterion derived by considering trial velocity field inspired from the Eshelby inhomogeneous inclusion solution. The obtained micromechanical model is implemented via a UMAT routine within the explicit dynamic code LS-DYNA. The proposed micromechanical model has been applied successfully for the modelling of some biomechanics applications to estimate the mechanical properties of the bovine trabecular bone.
Development of a finite element enriched method adapted for the case of multiple cracked structure
Authors: Durif Emilien , Réthoré Julien , Combescure Alain
Published: July 2021

The present method is based on the eXtended Finite Element Method and the partition of unity properties which allows the addition of enriched functions in the displacement field discretization. Those correspond to the analytical displacement field near a straight crack. The additionnal degrees of freedom correspond directly to the Stress Intensity Factors. This method is validated in mode 1 and mixed mode. A parametric study has been performed to analyse the effect of different parameters on the accuracy of the method. The case of two shading cracks has also been investigated.
Assessment of a smart concept for d15 shear piezoceramic direct torsion actuation
Authors: Benjeddou Ayech
Published: July 2021

An experimentally proved smart concept for piezoceramic direct torsion actuation is here numerically assessed with regards to the bonding and segmentation influence on its behavior and performance. The TRESCA and deflection criteria analysis indicates that the actuator sandwiching with composites contributes to its integrity enhancement, but in the cost of its performance reduction. It is also found that modeling the core inter-rows and composites inter-layers bonding is more influential than that of the core rows segmentation. The conducted open-circuit modal analysis confirms that the inter-rows adhesive softens the actuator, while the inter-layers one stiffens it. Besides, the conducted adhesive parametric analysis indicates that, as expected, the most influential bonding parameters are its thickness and shear modulus.
Vibration transfer analysis of component interfaces by a power flow mode approach
Authors: Weisser Thomas , Gonidou Luc-Olivier , Foltête Emmanuel , Bouhaddi Noureddine
Published: July 2021

A method has been developed to dynamically characterize complex structures’ interfaces at low frequencies. The aim is to optimize vibration isolation of a main structure subjected at its junctions to forces generated by connected substructures. An eigenvalue problem is formulated by minimizing the average dissipated power flow of the system. Hence, the derived eigenvalues and eigenvectors describe the energy pattern at each given frequency. It is then possible to characterize the real interface forces and, for example, to control them by determining the appropriated external forces to apply to the structure. This method has been studied on an academic system and applied to a simple coupled structure.
Deep- to near-ultraviolet Raman frequency conversion pumped by femtosecond pulses in a hollow-core waveguide
Authors: Shakano Taku , Zaitsu Shin-ichi , Imasaka Totaro
Published: July 2021

Broadband vibrational/rotational Raman generation ranging from deep ultraviolet (DUV) to blue wavelengths is demonstrated by using molecular hydrogen in a hollow-core waveguide as a Raman-active medium pumped by a femtosecond DUV laser. We find the high-order transient stimulated Raman scattering is drastically enhanced for input beams including a circularly polarized component; a circularly polarized input beam achieves the highest conversion efficiency. Coherent vibrational anti-Stokes Raman emission is observed only for a circularly polarized pump beam, indicating that the waveguide effect also contributes to the upconversion of a DUV pulse via transient stimulated Raman scattering.
Infrared and visible image fusion using salient decomposition based on
a generative adversarial network
Authors: Chen Lei , Han Jun
Published: July 2021

In order to address the fusion problem of infrared (IR) and visible images, this paper proposes a method using a local non-subsampled shearlet transform (LNSST) based on a generative adversarial network (GAN). We first decompose the source images into basic images and salient images by LNSST, then use two GANs fuse basic images and salient images. Lastly, we compose the fused basic images and salient images by inverse LNSST. We adopt public data sets to verify our method and by comparing with eight objective evaluation parameters obtained by 10 other methods. It is demonstrated that our method is able to achieve better performance than the state of the art on preserving both texture details and thermal information.
Measurement of a129Xe transverse relaxation rate without the influence of Rb polarization-induced magnetic gradient
Authors: Lee Deok-Young , Lee Sangkyung , Yim Sin Hyuk
Published: July 2021

We demonstrate the measurement of the transverse spin relaxation rate of Xe without the influence of the Rb polarization-induced magnetic field gradient. The optical pumping beam and probe beam turn on and off repeatedly during the measurement to reduce the relaxation originating from the Rb polarization-induced magnetic field gradient. During the absence of the optical pumping beam, the nuclear spin of the noble gas atom does not experience the alkali-polarization-induced magnetic field gradient so that the transverse spin relaxation rate (

1

/

T

2

) decreases. When the duty cycle reaches zero, the measured transverse relaxation time

T

2

approaches the longitudinal spin relaxation time

T

1

. Our method helps in roughly estimating the longitudinal spin relaxation time with a single measurement of the free induction decay.
3D reconstruction of structured light fields based on point cloud adaptive repair for highly reflective surfaces
Authors: Feng Wei , Qu Tong , Gao Junhui , Wang Henghui , Li Xiuhua , Zhai Zhongsheng , Zhao Daxing
Published: July 2021

In this paper, a novel method, to the best of our knowledge, of structured light fields based on point cloud adaptive repair is proposed to realize 3D reconstruction for highly reflective surfaces. We have designed and built a focused light field camera whose spatial and angular resolution can be flexibly adjusted as required. Then the subaperture image extraction algorithm based on image mosaic is deduced and presented to obtain multidirectional images. After that, the 3D reconstruction of structured light field imaging based on point cloud adaptive repair is presented to accurately reconstruct for highly reflective surfaces. In addition, a method based on smoothness and repair rate is also proposed to objectively evaluate the performance of the 3D reconstruction. Experimental results demonstrate the validity of the proposed method to perform high-quality depth reconstruction for highly reflective surfaces. Generally, our method takes advantage of the multidirectional imaging of the light field camera and can ensure good modulation effect of structured light while avoiding hardware complexity, which makes it application more convenient.
Multi-brightness layers with a genetic optimization algorithm for
stereo matching under dramatic illumination changes
Authors: Yang Tao , Yang Rui , Qiu Yuehong
Published: July 2021

Stereo matching under dramatic illumination changes is a big challenge in imbalanced
binocular vision, self-driving cars, and the remote sensing image
field. A novel, to the best of our knowledge, multi-brightness layer
mechanism with a genetic optimization algorithm is proposed in this
paper. The mechanism of multi-brightness layers transforms the two
images with dramatic illumination changes into a series of matched
pairs with similar brightness by the stretching function and histogram
matching principle. Therefore, the large illumination variations are
reduced greatly. Moreover, the initial disparities as first generation
of genetic optimization approach are generated from
matched pairs using fast segmentation local stereo matching to
increase the efficiency and accuracy. For further improving the
accuracy of disparity, an enhanced genetic optimization algorithm for
stereo matching is designed to have more inliers and continuity. The
experimental results comparing with state-of-the-art stereo matching
methods demonstrate that the proposed method has better performance in
accuracy and stability.
Shockwave enhancement from temporally separated filaments interacting with a water droplet
Authors: Peña Jessica , Kerrigan Haley , Richardson Martin
Published: July 2021

Many applications of filamentation require propagation through
aerosol-dense environments. The shockwave produced from a
filament–droplet interaction is one mechanism of clearing a path
through a dense cloud of aerosols. Here, we show an enhanced shockwave
resulting from the interaction of two temporally separated filaments
with a single water droplet. The expanding shockwave is imaged with an
ultrafast shadowgraphy technique, and Sedov–Taylor analysis determines
the energy coupled into the shockwave. For an optimal temporal spacing
between the filaments of 400 ps, the shockwave energy increased by 3
times and its radius increased by 1.23 times compared to the shockwave
generated by the interaction of a droplet with a single filament.
Self-referenced distribution of millimeter waves over 10  km optical fiber with high frequency stability
Authors: Yu Chunlong , Guo Hao , An Zhuoyan , Li Yihan , Zheng Zheng
Published: July 2021

In this Letter, an actively stabilized photonic system for millimeter-wave (mmW) signal distribution is proposed and experimentally demonstrated. By interlocking two baseband RF signals obtained from a dual-heterodyne detection through a single carrier compensation module, the phase fluctuations induced by the fiber transmission link is suppressed without the need of a local frequency reference. In the proof-of-concept experiment, a 108 GHz mmW is transmitted over a 10 km fiber link with a performance matching that of the back-to-back case. The feedback system reduces the phase noise of the delivered mmW signal by 37 dB and 28 dB at 0.1 Hz and 1 Hz frequency offset, respectively, and the long-term stability is improved by nearly two orders of magnitude.
Anisotropy of 2PA, 3PA, and Kerr effect in nonpolar ZnO
Authors: Hua Shijia , Zhang Wending
Published: July 2021

Anisotropic optical nonlinearity plays an important role in polarization-dependent optoelectronic devices. Taking the advantage of in-plane crystallographic axis, the polarization dependence of third- and fifth-order nonlinearity in nonpolar ZnO has been investigated by

z

scan. Here, we established the theory model of anisotropic relation of fifth-order nonlinearity in hexagonal wurtzite crystal. Both two-photon absorption (2PA) and three-photon absorption (3PA) coefficients exhibit anisotropic oscillations with a period of 180°, and the polarization modulation factor and anisotropy coefficient

(

r

p

,

σ

)

are measured as (2.10, 1.84) for

β

2

, and (1.66, 1.33) for

β

3

, respectively. This is the first time, to the best of our knowledge, that the anisotropy of the fifth-order optical nonlinear effect has been characterized and confirmed. It is verified that the self-defocusing effect at 500 nm is isotropy, while the self-focusing effect at 800 nm exhibits significant anisotropy. The maximum value of the nonlinear figure of merit is 5.84 along the [0010] crystalline direction, nearly 1.6 times the minimum value, revealing that ZnO exhibits potential for nonlinear applications containing polarization-related all-optical switching components.
Quantized Fourier ptychography with binary images from SPAD cameras
Authors: Yang Xi , Konda Pavan Chandra , Xu Shiqi , Bian Liheng , Horstmeyer Roarke
Published: July 2021

Recently developed single-photon avalanche diode (SPAD) array cameras provide single-photon sensitivity and picosecond-scale time gating for time-of-flight measurements, with applications in LIDAR and fluorescence lifetime imaging. As compared to standard image sensors, SPAD arrays typically return binary intensity measurements with photon time-of-arrival information from fewer pixels. Here, we study the feasibility of implementing Fourier ptychography (FP), a synthetic aperture imaging technique, with SPAD array cameras to reconstruct an image with higher resolution and larger dynamic range from acquired binary intensity measurements. Toward achieving this goal, we present (1) an improved FP reconstruction algorithm that accounts for discretization and limited bit depth of the detected light intensity by image sensors, and (2) an illumination angle-dependent source brightness adaptation strategy, which is sample-specific. Together, these provide a high-quality amplitude and phase object reconstruction, not only from binary SPAD array intensity measurements, but also from alternative low-dynamic-range images, as demonstrated by our simulations and proof-of-concept experiments.
Distributed polymer optical fiber sensors: a review and outlook
Authors: Mizuno Yosuke , Theodosiou Antreas , Kalli Kyriacos , Liehr Sascha , Lee Heeyoung , Nakamura Kentaro
Published: July 2021

Aging degradation and seismic damage of civil infrastructures have become a serious issue for society, and one promising technology for monitoring their conditions is optical fiber sensing. Glass optical fibers have been predominantly used for the past several decades to develop fiber sensors, but currently polymer or plastic optical fibers (POFs) have also been used extensively to develop advanced fiber sensors because of their unique features, such as high flexibility, large breakage strain, and impact resistance. This review focuses on recently developed distributed and quasi-distributed POF-based sensing techniques based on Rayleigh scattering, Brillouin scattering, and fiber Bragg gratings.
Integration of sleep homeostasis and navigation in Drosophila
Authors: Flores-Valle Andres , Gonçalves Pedro J. , Seelig Johannes D.
Published: July 2021

During sleep, the brain undergoes dynamic and structural changes. In Drosophila, such changes have been observed in the central complex, a brain area important for sleep control and navigation. The connectivity of the central complex raises the question about how navigation, and specifically the head direction system, can operate in the face of sleep related plasticity. To address this question, we develop a model that integrates sleep homeostasis and head direction. We show that by introducing plasticity, the head direction system can function in a stable way by balancing plasticity in connected circuits that encode sleep pressure. With increasing sleep pressure, the head direction system nevertheless becomes unstable and a sleep phase with a different plasticity mechanism is introduced to reset network connectivity. The proposed integration of sleep homeostasis and head direction circuits captures features of their neural dynamics observed in flies and mice.
OpenABM-Covid19—An agent-based model for non-pharmaceutical interventions against COVID-19 including contact tracing
Authors: Hinch Robert , Probert William J. M. , Nurtay Anel , Kendall Michelle , Wymant Chris , Hall Matthew , Lythgoe Katrina , Bulas Cruz Ana , Zhao Lele , Stewart Andrea , Ferretti Luca , Montero Daniel , Warren James , Mather Nicole , Abueg Matthew , Wu Neo , Legat Olivier , Bentley Katie , Mead Thomas , Van-Vuuren Kelvin , Feldner-Busztin Dylan , Ristori Tommaso , Finkelstein Anthony , Bonsall David G. , Abeler-Dörner Lucie , Fraser Christophe
Published: July 2021

SARS-CoV-2 has spread across the world, causing high mortality and unprecedented restrictions on social and economic activity. Policymakers are assessing how best to navigate through the ongoing epidemic, with computational models being used to predict the spread of infection and assess the impact of public health measures. Here, we present OpenABM-Covid19: an agent-based simulation of the epidemic including detailed age-stratification and realistic social networks. By default the model is parameterised to UK demographics and calibrated to the UK epidemic, however, it can easily be re-parameterised for other countries. OpenABM-Covid19 can evaluate non-pharmaceutical interventions, including both manual and digital contact tracing, and vaccination programmes. It can simulate a population of 1 million people in seconds per day, allowing parameter sweeps and formal statistical model-based inference. The code is open-source and has been developed by teams both inside and outside academia, with an emphasis on formal testing, documentation, modularity and transparency. A key feature of OpenABM-Covid19 are its Python and R interfaces, which has allowed scientists and policymakers to simulate dynamic packages of interventions and help compare options to suppress the COVID-19 epidemic.
Detecting behavioural changes in human movement to inform the spatial scale of interventions against COVID-19
Authors: Gibbs Hamish , Nightingale Emily , Liu Yang , Cheshire James , Danon Leon , Smeeth Liam , Pearson Carl A. B. , Grundy Chris ,   LSHTM CMMID COVID-19 working group, Kucharski Adam J. , Eggo Rosalind M.
Published: July 2021

On March 23 2020, the UK enacted an intensive, nationwide lockdown to mitigate transmission of COVID-19. As restrictions began to ease, more localized interventions were used to target resurgences in transmission. Understanding the spatial scale of networks of human interaction, and how these networks change over time, is critical to targeting interventions at the most at-risk areas without unnecessarily restricting areas at low risk of resurgence. We use detailed human mobility data aggregated from Facebook users to determine how the spatially-explicit network of movements changed before and during the lockdown period, in response to the easing of restrictions, and to the introduction of locally-targeted interventions. We also apply community detection techniques to the weighted, directed network of movements to identify geographically-explicit movement communities and measure the evolution of these community structures through time. We found that the mobility network became more sparse and the number of mobility communities decreased under the national lockdown, a change that disproportionately affected long distance connections central to the mobility network. We also found that the community structure of areas in which locally-targeted interventions were implemented following epidemic resurgence did not show reorganization of community structure but did show small decreases in indicators of travel outside of local areas. We propose that communities detected using Facebook or other mobility data be used to assess the impact of spatially-targeted restrictions and may inform policymakers about the spatial extent of human movement patterns in the UK. These data are available in near real-time, allowing quantification of changes in the distribution of the population across the UK, as well as changes in travel patterns to inform our understanding of the impact of geographically-targeted interventions.
Bayesian back-calculation and nowcasting for line list data during the COVID-19 pandemic
Authors: Li Tenglong , White Laura F.
Published: July 2021

Surveillance is critical to mounting an appropriate and effective response to pandemics. However, aggregated case report data suffers from reporting delays and can lead to misleading inferences. Different from aggregated case report data, line list data is a table contains individual features such as dates of symptom onset and reporting for each reported case and a good source for modeling delays. Current methods for modeling reporting delays are not particularly appropriate for line list data, which typically has missing symptom onset dates that are non-ignorable for modeling reporting delays. In this paper, we develop a Bayesian approach that dynamically integrates imputation and estimation for line list data. Specifically, this Bayesian approach can accurately estimate the epidemic curve and instantaneous reproduction numbers, even with most symptom onset dates missing. The Bayesian approach is also robust to deviations from model assumptions, such as changes in the reporting delay distribution or incorrect specification of the maximum reporting delay. We apply the Bayesian approach to COVID-19 line list data in Massachusetts and find the reproduction number estimates correspond more closely to the control measures than the estimates based on the reported curve.
Essential gene acquisition destabilizes plasmid inheritance
Authors: Wein Tanita , Wang Yiqing , Barz Myriam , Stücker Fenna T. , Hammerschmidt Katrin , Dagan Tal
Published: July 2021

Extra-chromosomal genetic elements are important drivers of evolutionary transformations and ecological adaptations in prokaryotes with their evolutionary success often depending on their ‘utility’ to the host. Examples are plasmids encoding antibiotic resistance genes, which are known to proliferate in the presence of antibiotics. Plasmids carrying an essential host function are recognized as permanent residents in their host. Essential plasmids have been reported in several taxa where they often encode essential metabolic functions; nonetheless, their evolution remains poorly understood. Here we show that essential genes are rarely encoded on plasmids; evolving essential plasmids in Escherichia coli we further find that acquisition of an essential chromosomal gene by a plasmid can lead to plasmid extinction. A comparative genomics analysis of Escherichia isolates reveals few plasmid-encoded essential genes, yet these are often integrated into plasmid-related functions; an example is the GroEL/GroES chaperonin. Experimental evolution of a chaperonin-encoding plasmid shows that the acquisition of an essential gene reduces plasmid fitness regardless of the stability of plasmid inheritance. Our results suggest that essential plasmid emergence leads to a dose effect caused by gene redundancy. The detrimental effect of essential gene acquisition on plasmid inheritance constitutes a barrier for plasmid-mediated lateral gene transfer and supplies a mechanistic understanding for the rarity of essential genes in extra-chromosomal genetic elements.
Genome mapping coupled with CRISPR gene editing reveals a P450 gene confers avermectin resistance in the beet armyworm
Authors: Zuo Yayun , Shi Yu , Zhang Feng , Guan Fang , Zhang Jianpeng , Feyereisen René , Fabrick Jeffrey A. , Yang Yihua , Wu Yidong
Published: July 2021

The evolution of insecticide resistance represents a global constraint to agricultural production. Because of the extreme genetic diversity found in insects and the large numbers of genes involved in insecticide detoxification, better tools are needed to quickly identify and validate the involvement of putative resistance genes for improved monitoring, management, and countering of field-evolved insecticide resistance. The avermectins, emamectin benzoate (EB) and abamectin are relatively new pesticides with reduced environmental risk that target a wide number of insect pests, including the beet armyworm,Spodoptera exigua, an important global pest of many crops. Unfortunately, field resistance to avermectins recently evolved in the beet armyworm, threatening the sustainable use of this class of insecticides. Here, we report a high-quality chromosome-level assembly of the beet armyworm genome and use bulked segregant analysis (BSA) to identify the locus of avermectin resistance, which mapped on 15–16 Mbp of chromosome 17. Knockout of theCYP9A186gene that maps within this region by CRISPR/Cas9 gene editing fully restored EB susceptibility, implicating this gene in avermectin resistance. Heterologous expression andin vitrofunctional assays further confirm that a natural substitution (F116V) found in the substrate recognition site 1 (SRS1) of the CYP9A186 protein results in enhanced metabolism of EB and abamectin. Hence, the combined approach of coupling gene editing with BSA allows for the rapid identification of metabolic resistance genes responsible for insecticide resistance, which is critical for effective monitoring and adaptive management of insecticide resistance.
Genes involved in immune, gene translation and chromatin organization pathways associated with Mycoplasma ovipneumoniae presence in nasal secretions of domestic sheep
Authors: Mousel Michelle R. , White Stephen N. , Herndon Maria K. , Herndon David R. , Taylor J. Bret , Becker Gabrielle M. , Murdoch Brenda M.
Published: July 2021

Mycoplasma ovipneumoniae contributes to polymicrobial pneumonia in domestic sheep. Elucidation of host genetic influences of M. ovipneumoniae nasal detection has the potential to reduce the incidence of polymicrobial pneumonia in sheep through implementation of selective breeding strategies. Nasal mucosal secretions were collected from 647 sheep from a large US sheep flock. Ewes of three breeds (Polypay n = 222, Rambouillet n = 321, and Suffolk n = 104) ranging in age from one to seven years, were sampled at three different times in the production cycle (February, April, and September/October) over four years (2015 to 2018). The presence and DNA copy number of M. ovipneumoniae was determined using a newly developed species-specific qPCR. Breed (P<0.001), age (P<0.024), sampling time (P<0.001), and year (P<0.001) of collection affected log10 transformed M. ovipneumoniae DNA copy number, where Rambouillet had the lowest (P<0.0001) compared with both Polypay and Suffolk demonstrating a possible genetic component to detection. Samples from yearlings, April, and 2018 had the highest (P<0.046) detected DNA copy number mean. Sheep genomic DNA was genotyped with the Illumina OvineHD BeadChip. Principal component analysis identified most of the variation in the dataset was associated with breed. Therefore, genome wide association analysis was conducted with a mixed model (EMMAX), with principal components 1 to 6 as fixed and a kinship matrix as random effects. Genome-wide significant (P<9x10-8) SNPs were identified on chromosomes 6 and 7 in the all-breed analysis. Individual breed analysis had genome-wide significant (P<9x10-8) SNPs on chromosomes 3, 4, 7, 9, 10, 15, 17, and 22. Annotated genes near these SNPs are part of immune (ANAPC7, CUL5, TMEM229B, PTPN13), gene translation (PIWIL4), and chromatin organization (KDM2B) pathways. Immune genes are expected to have increased expression when leukocytes encounter M. ovipneumoniae which would lead to chromatin reorganization. Work is underway to narrow the range of these associated regions to identify the underlying causal mutations.
Patients’ E-Readiness to use E-Health technologies for oral health
Authors: Jagde Arishdeep Kaur , Shrivastava Richa , Feine Jocelyne , Emami Elham
Published: July 2021

Introduction

Scientific evidence highlights the importance of E-Readiness in the adoption and implementation of E-Oral Health technologies. However, to our knowledge, there is no study investigating the perspective of patients in this regard. Therefore, the objective of this study was to explore patients’ E-Readiness in the field of dentistry.

Materials and methods

A qualitative study was conducted using interpretive descriptive methodology. Purposeful sampling with maximum variation and snowball techniques were used to recruit the study participants via McGill University dental clinics and affiliated hospitals, as well as private or public dental care organizations. A total of 15 face-to-face, semi-structured and 60 to 90-minute audio recorded interviews were conducted. Data collection and analyses were performed concurrently, and interviews were continued until saturation was reached. Activity theory was used as the conceptual framework, and thematic analysis was used to analyze data. Data analysis was conducted both manually and with the use of “ATLAS-ti” software.

Results

Four major themes emerged from the study; unlocking barriers, E-Oral Health awareness, inquisitiveness for E-Oral Health technology and enduring oral health benefits. These themes correspond with all three types of readiness (core, engagement and structural).

Conclusion

The study results suggest that dental patients consider E-Oral Health as a facilitator to access to care, and they are ready to learn and use E-Oral Health technology. There is a need to implement and support E-Oral Health technologies to improve patient care.
Psychological stress and associated factors among municipal solid waste collectors in Hanoi, Vietnam: A cross-sectional study
Authors: Nguyen Quynh Thuy , Nguyen Bang Van , Do Ha Thi Thu , Nguyen Bich Ngoc , Nguyen Van Thanh , Vu Son Thai , Tran Thuy Thi Thu
Published: July 2021

Introduction

In low and middle-income countries, the manually operated municipal waste collection system prominently depended on the performance of waste collectors (WC). Most of the literature has focused on the impact of waste collection tasks on WCs’ physical health, while little was known about the psychological effects of work-related stress. This study aimed to examine the prevalence of psychological stress and related factors among waste collectors in Hanoi, Vietnam.

Methods

A cross-sectional survey was conducted among 802 WCs in 2017. The questionnaire included the 7-item Stress component of the 21-item Depression, Anxiety and Stress Scale, and questions on demographics and work conditions. Descriptive and multivariate logistics regression analyses were conducted to examine the factors related to psychological stress among WCs.

Results

Results showed that 13.4% of WCs reported stress symptoms; among them, 3.3% of WCs experienced severe stress. Factors related to lower odds of self-reported psychological stress included self-perceived frequent exposure to high and low temperatures in the working environment (OR = 0.51 and 0.52, respectively). Factors associated with the increased likelihood of symptoms included frequent exposure to hot/flammable objects (OR = 2.41), working a night shift in the last three months (OR = 1.82), education lever lower than high school (OR = 1.82), and having an insufficient monthly income (OR = 1.99).

Conclusion

The high percentage of workers with severe stress implies the need for mental health prevention and treatment for WCs who participated in this study.
Identification and validation of a novel ferroptosis-related gene model for predicting the prognosis of gastric cancer patients
Authors: Liu Gang , Ma Jian-ying , Hu Gang , Jin Huan
Published: July 2021

Background

Ferroptosis is a novel form of regulated cell death that plays a critical role in tumorigenesis. The purpose of this study was to establish a ferroptosis-associated gene (FRG) signature and assess its clinical outcome in gastric cancer (GC).

Methods

Differentially expressed FRGs were identified using gene expression profiles from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. Univariate and least absolute shrinkage and selection operator (LASSO) Cox regression analyses were performed to construct a prognostic signature. The model was validated using an independent GEO dataset, and a genomic-clinicopathologic nomogram integrating risk scores and clinicopathological features was established.

Results

An 8-FRG signature was constructed to calculate the risk score and classify GC patients into two risk groups (high- and low-risk) according to the median value of the risk score. The signature showed a robust predictive capacity in the stratification analysis. A high-risk score was associated with advanced clinicopathological features and an unfavorable prognosis. The predictive accuracy of the signature was confirmed using an independent GSE84437 dataset. Patients in the two groups showed different enrichment of immune cells and immune-related pathways. Finally, we established a genomic-clinicopathologic nomogram (based on risk score, age, and tumor stage) to predict the overall survival (OS) of GC patients.

Conclusions

The novel FRG signature may be a reliable tool for assisting clinicians in predicting the OS of GC patients and may facilitate personalized treatment.
The interplay of Rac1 activity, ubiquitination and GDI binding and its consequences for endothelial cell spreading
Authors: Majolée Jisca , Podieh Fabienne , Hordijk Peter L. , Kovačević Igor
Published: July 2021

Signaling by the Rho GTPase Rac1 is key to the regulation of cytoskeletal dynamics, cell spreading and adhesion. It is widely accepted that the inactive form of Rac1 is bound by Rho GDI, which prevents Rac1 activation and Rac1-effector interactions. In addition, GDI-bound Rac1 is protected from proteasomal degradation, in line with data showing that Rac1 ubiquitination occurs exclusively when Rac1 is activated. We set out to investigate how Rac1 activity, GDI binding and ubiquitination are linked. We introduced single amino acid mutations in Rac1 which differentially altered Rac1 activity, and compared whether the level of Rac1 activity relates to Rac1 ubiquitination and GDI binding. Results show that Rac1 ubiquitination and the active Rac1 morphology is proportionally increased with Rac1 activity. Similarly, we introduced lysine-to-arginine mutations in constitutively active Rac1 to inhibit site-specific ubiquitination and analyze this effect on Rac1 signaling output and ubiquitination. These data show that the K16R mutation inhibits GTP binding, and consequently Rac1 activation, signaling and–ubiquitination, while the K147R mutation does not block Rac1 signaling, but does inhibits its ubiquitination. In both sets of mutants, no direct correlation was observed between GDI binding and Rac1 activity or -ubiquitination. Taken together, our data show that a strong, positive correlation exists between Rac1 activity and its level of ubiquitination, but also that GDI dissociation does not predispose Rac1 to ubiquitination.
Self-reported gender differentials in the knowledge of tuberculosis transmission and curative possibility using national representative data in Ghana
Authors: Boah Michael , Kpordoxah Mary Rachael , Adokiya Martin Nyaaba
Published: July 2021

Background

Health-seeking behaviour, stigma, and discrimination towards people affected by tuberculosis (TB) are influenced by awareness of the disease. Gender differentials in the diagnosis and treatment of TB have been reported in other settings of the world. However, little is known about the gender differences in the knowledge of TB transmission and curative possibility in Ghana.

Methods

The analysed data were a weighted sample of 9,396 women aged 15–49 years and 4,388 men aged 15–59 years, obtained from the 2014 Ghana Demographic and Health Survey. The dependent variable, correct knowledge regarding TB transmission and cure was derived from questions on the transmission of the disease and the possibility of a cure. A design-based multivariate logistic regression model in Stata 13.0/SE was used to identify the correlates of reporting correct knowledge.

Results

Overall, the mean knowledge score was 6.1±0.9 (maximum = 7). Of the 13,784 respondents, 45.7% (95% CI: 44.0–47.3) reported correct knowledge regarding TB transmission and cure. Men had significantly higher knowledge than women (50.9% versus 43.2%). Misconceptions, including TB transmitted through sharing utensils (13.3%), food (6.9%), touching a person with TB (4.5%), sexual contact (4.1%), and mosquito bites (0.4%) were noted. About 30% (33% women and 25% men) of the total sample would keep the information secret when a household member is affected with TB. In the adjusted analysis, age, gender, education, region, place of residence, wealth quintile, frequency of reading newspaper/magazine, listening to the radio, and watching television were significantly associated with reporting correct knowledge.

Conclusions

There was low knowledge regarding TB transmission and cure. Misconceptions regarding the transmission of TB prevailed among the participants. Gender differential in knowledge was observed. Comparatively, females were less likely to be aware of TB and report correct knowledge regarding TB transmission but were more likely to conceal information when a household member was affected by the disease.
Incidence and trends of limb amputation in first nations and general population in Saskatchewan, 2006–2019
Authors: Essien Samuel Kwaku , Linassi Gary , Larocque Margaret , Zucker-Levin Audrey
Published: July 2021

Background

There is conflicting evidence whether limb amputation (LA) disproportionately affects indigenous populations. To better understand this disparity, we compared the LA incidence rate between First Nations persons registered under the Indian Act of Canada (RI) and the general population (GP) in Saskatchewan.

Methods

We used Saskatchewan’s retrospective administrative data containing hospital discharge LA cases, demographic characteristics (age and sex), and residents population reported in the database stratified by RI and GP from 2006–2019. The LA cases for each stratified group were first disaggregated into three broad categories: overall LA (all reported LA), primary LA (first reported LA), and subsequent LA (revision or contralateral LA), with each category further split into the level of amputation defined as major amputation (through/above the ankle/wrist joint) and minor amputation (below the ankle/wrist joint). LA rates were calculated using LA cases as the numerator and resident population as the denominator. Joinpoint and negative binomial regressions were performed to explore the trends further.

Results

Overall, there were 1347 RI and 4520 GP LA cases reported in Saskatchewan from 2006–2019. Primary LA made up approximately 64.5% (869) of RI and 74.5% (3369) of GP cases, while subsequent LA constituted 35.5% (478) of RI and 25.5% (1151) of GP cases. The average age-adjusted LA rate was 153.9 ± 17.3 per 100,000 in the RI cohort and 31.1 ± 2.3 per 100,000 in the GP cohort. Overall and primary LA rates for the GP Group declined 0.7% and 1.0%, while subsequent LA increased 0.1%. An increased LA rate for all categories (overall 4.9%, primary 5.1%, and subsequent 4.6%) was identified in the RI group. Overall, minor and major LA increased by 6.2% and 3.3%, respectively, in the RI group compared to a 0.8% rise in minor LA and a 6.3% decline in major LA in the GP group. RI females and males were 1.98–1.66 times higher risk of LA than their GP counterparts likewise, RI aged 0–49 years and 50+ years were 2.04–5.33 times higher risk of LA than their GP cohort. Diabetes mellitus (DM) was the most prevalent amputation predisposing factor in both groups with 81.5% of RI and 54.1% of GP diagnosed with DM. Also, the highest proportion of LA was found in the lowest income quintile for both groups (68.7% for RI and 45.3% for GP).

Conclusion

Saskatchewan’s indigenous individuals, specifically First Nations persons registered under the Indian Act of Canada, experience LA at a higher rate than the general population. This disparity exists for all variables examined, including overall, primary, and subsequent LA rates, level of amputation, sex, and age. Amplification of the disparities will continue if the rates of change maintain their current trajectories. These results underscore the need for a better understanding of underlying causes to develop a targeted intervention in these groups.
Strategies to target SARS-CoV-2 entry and infection using dual mechanisms of inhibition by acidification inhibitors
Authors: Prabhakara Chaitra , Godbole Rashmi , Sil Parijat , Jahnavi Sowmya , Gulzar Shah-e-Jahan , van Zanten Thomas S. , Sheth Dhruv , Subhash Neeraja , Chandra Anchal , Shivaraj Akshatha , Panikulam Patricia , U Ibrahim , Nuthakki Vijay Kumar , Puthiyapurayil Theja Parassini , Ahmed Riyaz , Najar Ashaq Hussain , Lingamallu Sai Manoz , Das Snigdhadev , Mahajan Bhagyashri , Vemula Praveen , Bharate Sandip B. , Singh Parvinder Pal , Vishwakarma Ram , Guha Arjun , Sundaramurthy Varadharajan , Mayor Satyajit
Published: July 2021

Many viruses utilize the host endo-lysosomal network for infection. Tracing the endocytic itinerary of SARS-CoV-2 can provide insights into viral trafficking and aid in designing new therapeutic strategies. Here, we demonstrate that the receptor binding domain (RBD) of SARS-CoV-2 spike protein is internalized via the pH-dependent CLIC/GEEC (CG) endocytic pathway in human gastric-adenocarcinoma (AGS) cells expressing undetectable levels of ACE2. Ectopic expression of ACE2 (AGS-ACE2) results in RBD traffic via both CG and clathrin-mediated endocytosis. Endosomal acidification inhibitors like BafilomycinA1 and NH4Cl, which inhibit the CG pathway, reduce the uptake of RBD and impede Spike-pseudoviral infection in both AGS and AGS-ACE2 cells. The inhibition by BafilomycinA1 was found to be distinct from Chloroquine which neither affects RBD uptake nor alters endosomal pH, yet attenuates Spike-pseudovirus entry. By screening a subset of FDA-approved inhibitors for functionality similar to BafilomycinA1, we identified Niclosamide as a SARS-CoV-2 entry inhibitor. Further validation using a clinical isolate of SARS-CoV-2 in AGS-ACE2 and Vero cells confirmed its antiviral effect. We propose that Niclosamide, and other drugs which neutralize endosomal pH as well as inhibit the endocytic uptake, could provide broader applicability in subverting infection of viruses entering host cells via a pH-dependent endocytic pathway.