bluuebunny/crossref_metadata_2025 huggingface dataset:
Demand Learning and Pricing for Varying Assortments
Authors: Ferreira Kris Johnson , Mower Emily
Published: March 2022

Problem definition: We consider the problem of demand learning and pricing for retailers who offer assortments of substitutable products that change frequently, for example, due to limited inventory, perishable or time-sensitive products, or the retailer’s desire to frequently offer new styles. Academic/practical relevance: We are one of the first to consider the demand learning and pricing problem for retailers who offer product assortments that change frequently, and we propose and implement a learn-then-earn algorithm for use in this setting. Our algorithm prioritizes a short learning phase, an important practical characteristic that is only considered by few other algorithms. Methodology: We develop a novel demand learning and pricing algorithm that learns quickly in an environment with varying assortments and limited price changes by adapting the commonly used marketing technique of conjoint analysis to our setting. We partner with Zenrez, an e-commerce company that partners with fitness studios to sell excess capacity of fitness classes, to implement our algorithm in a controlled field experiment to evaluate its effectiveness in practice using the synthetic control method. Results: Relative to a control group, our algorithm led to an expected initial dip in revenue during the learning phase, followed by a sustained and significant increase in average daily revenue of 14%–18% throughout the earning phase, illustrating that our algorithmic contributions can make a significant impact in practice. Managerial implications: The theoretical benefit of demand learning and pricing algorithms is well understood—they allow retailers to optimally match supply and demand in the face of uncertain preseason demand. However, most existing demand learning and pricing algorithms require substantial sales volume and the ability to change prices frequently for each product. Our work provides retailers who do not have this luxury a powerful demand learning and pricing algorithm that has been proven in practice.

History: This paper has been accepted as part of the 2021 Manufacturing & Service Operations Management Practice-Based Research Competition.

Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.1080 .
Z-frenuloplasty: A Versatile and Effective Technique
Authors: Menhadji Payvand , Raindi Devan S , Malhi Meenakshi , Boodhooa Angela
Published: March 2022

There are various cases where Z-frenuloplasty, a specific Z-plasty technique, can be used, including prior to mucogingival surgery, to manage localized recession defects, pre-prosthetic surgery, post-orthodontic treatment, oral hygiene and ankyloglossia, to name a few. This case series demonstrates the versatility of the Z-plasty technique in oral surgery/periodontal procedures for a variety of indications, as well as describing the technique in detail. The frenectomy technique using Z-plasty for the removal of the abnormal labial frenum attachment is reliable, easy to perform, and provides excellent aesthetic results for a range of indications.

CPD/Clinical Relevance: An appreciation of the Z-plasty technique will allow for tissue healing by primary intention, reduces risk of tissue contractures, improves recovery time, and improves aesthetic results.
Update on Medically Compromised Patients for Oral Surgery: The Bleeders and the Non-healers
Authors: Woolcombe Sarah , Taylor Talli , Renton Tara
Published: March 2022

Coagulation and wound healing following oral surgery procedures involve a number of intricate steps. The disturbance of normal physiological processes can be influenced by local and systemic factors that affect post-operative bleeding and healing of the surgical site. This article provides an update on medical conditions and medications, to aid identification of susceptible individuals, and describes the appropriate management of patients presenting with post-operative bleeding or a non-healing socket.

CPD/Clinical Relevance: An understanding of post-operative bleeding and non-healing helps to prevent their occurrence and assists with optimal management when they do present.
What Teachers Tell Us About the Impact of the COVID-19 Pandemic on Public Education in Italy
Authors: Decarli Gisella , Surian Luca , Vignoli Michela , Franchin Laura
Published: March 2022

The Coronavirus disease (COVID-19) state of emergency has brought about a radical change in the way of teaching. In a questionnaire, we asked 120 teachers from Italian Primary, Middle and High Schools about the advantages and disadvantages of online teaching, the students’ conduct during lessons and the methodologies applied to students with special educational needs. Primary School teachers most strongly reported an increase in boredom and distraction, and disagreed that online teaching helps students’ learning and that it makes them more active. The main advantage of online teaching was the technical and methodological innovations, while the main disadvantage was the lack of relationship with students. In the case of students with special educational needs, many teachers reported that they used simplified procedures and personalized meetings. Overall, teachers appear to think that online teaching has many drawbacks, though it also has some positive aspects that need to be appreciated and exploited.
Singularidades da enfermagem em Unidades da Estratégia Saúde da Família de Feira de Santana, Bahia
Authors: Couto de Almeida Tatiane Santos , Coelho Thereza Christina Bahia
Published: March 2022

Este artigo tem por objetivo analisar e discutir o processo de trabalho de enfermeiras(os) que atuavam na ESF enfermeiro da Estratégia de Saúde da Família (ESF). Trata-se de um estudo de caso, qualitativo, com oito profissionais da enfermagem, de nível superior. As técnicas de coleta de dados utilizadas foram a entrevista semiestruturada e observação sistemática e o método de análise, a de conteúdo do tipo temático. Os resultados identificaram uma percepção de prazer relacionada à redução do sofrimento do outro e o reconhecimento decorrente. Tal percepção de bem-estar também se associava à satisfação com o trabalho. Embora existissem facilidades para a execução do trabalho, as dificuldades se mostraram-se mais enfáticas e, em sua maioria, fora do poder de governabilidade da(o) enfermeira(o). O desgaste provinha da sobrecarga de atividades, do excesso de fazeres burocráticos e participação incipiente da comunidade nas atividades educativas da ESF. As estratégias de enfrentamento apontaram para táticas individualizadas pouco eficazes para a transposição do sofrimento laboral com nuances de comportamentos submissos, uso de atividades evasivas, como lazer, atividade física, busca religiosa, conversas, ações pontuais que não incidiam diretamente sobre as causas do sofrimento laboral, nem na transformação do trabalho e do sujeito.
Laser-induced schliere anemometry in a Mach 6 flow with collinear light entry
Authors: Chism James R. , Gragston Mark , Hagen Ben , Leicht Jason , Riley Zachary B.
Published: March 2022

In this work, we demonstrate velocity, Mach number, and static temperature measurements in a Mach 6 flow using the recently developed laser-induced schliere anemometry (LISA) technique. To our best knowledge, this represents the first application of LISA for characterizing flow in the hypersonic Mach number regime, and a comparison with known tunnel values is provided. The laser-induced schliere in this work are written from a distance of roughly 76 cm away from the final lens, much further than in previous work. Furthermore, the schliere are created from a laser beam introduced parallel to the collimated schlieren light, which is a new arrangement that could be useful for facilities with limited optical access. A discussion of setup limitations is provided. The mean core flow velocity determined from LISA is within 1% of the expected value from isentropic theory, while the mean Mach number measurements are within 1.6% of the

M
=
5.85

value used in literature for the facility. Furthermore, the determined mean static temperature of the core flow is within 2.5% of the value measured simultaneously in the facility.
Fast path planning algorithm for large-aperture aspheric optical
elements based on minimum object depth and a self-optimized overlap
coefficient
Authors: Wang Fanyi , Yang Yongying , Lou Weiming
Published: March 2022

In the procedure of surface defects detection of large-aperture aspheric optical elements, it is necessary to scan the surface of the element to achieve full coverage inspection. Since the curvature of the aspherical element is constantly changing from the center to the edge, it is of great difficulty to carry out efficient path planning. In addition, the machine vision system is a microscopic system with limited depth of field, and the sub-aperture imaging of aspherical elements has a visual depth along the object side. When the object depth is greater than the depth of field, out-of-focus blur will generate, so the object depth needs to be as small as possible. In response to these problems, this paper proposes a fast path planning algorithm based on the minimum object depth of a sub-aperture. To ensure minimum object depth, the machine vision system collects images along the normal direction of the sub-aperture plane. To address the problem of the surface curvatures of aspheric elements being different and the overlap coefficient difficult to determine, this paper proposes an image processing based overlap coefficient self-optimization algorithm. When scanning with full coverage of elements, there is only one connected domain in the horizontal projection image of all sub-apertures. According to this premise, the overlap coefficient is optimized through an image processing method to obtain a local optimal path planning strategy. According to the obtained path planning strategy, combining the component parameters and mechanical structure, the mapping matrix of the path planning algorithm transplanted to the detection system is calculated. Through computer programming, automatic sub-aperture acquisition is realized, and the self-edited sub-aperture stitching program is applied to reconstruct the collected sub-apertures. Our algorithm can complete path planning within 5 s, and the experimental results show that the maximum stitching misalignment error of the collected sub-apertures is no more than four pixels, and the average is one pixel. The reconstruction accuracy satisfies the needs of subsequent image processing and digital quantization.
Reconfigurable and spectrally switchable perfect absorber based on a
phase-change material
Authors: Prakash S Ram , Kumar Rajesh , Mitra Anirban
Published: March 2022

In this paper, we propose a lithography-free spectrally tunable prefect absorber based
on an asymmetric Fabry–Perot cavity using

G
e

2

S
b

2

T
e

5

(GST), a phase-change material, as
the cavity layer. The proposed device shows a maximum absorption of
99.7% at 1550 nm, at a particular angle of incidence and polarization
when the phase of GST is in the amorphous state. The absorption
spectrum is spectrally switched to longer wavelength when the phase of
GST is transformed from amorphous to crystalline. The tuning range is
about 866 nm, and the maximum absorption is maintained above 99% in
the whole tuning range. The crystallinity ratio of GST is varied by
applying voltage pulses of different amplitudes and durations. The
electrothermal cosimulations show that the phase change is obtained in
the whole GST layer. Furthermore, by reamorphization of GST, the
absorption spectrum can be switched back, enabling a reconfigurable
perfect absorber. This work shows a viable path toward achieving a
tunable perfect absorber covering a 1550 nm communication wavelength
window as well as an emerging optical communication window around 2 µm
wavelength.
Design of an efficient illuminator for partially coherent sources in
the extreme ultraviolet
Authors: Lüttgenau Bernhard , Panitzek Dieter , Danylyuk Serhiy , Brose Sascha , Stollenwerk Jochen , Loosen Peter , Holly Carlo
Published: March 2022

In this paper, the design of an efficient illuminator for extreme ultraviolet (EUV) applications such as photolithography, metrology, and microscopy is investigated. Illuminators are arrangements of optical components that allow us to tailor optical parameters to a targeted application. For the EUV spectral range, illuminators are commonly realized by an arrangement of several multilayer mirrors. Within this publication, design methods are developed to tailor optical parameters such as the intensity distribution, the spatial coherence, and the spectral bandwidth by using only one multilayer mirror. For the demonstration of the methods, an illuminator is designed for a compact in-lab EUV interference lithography system that is suited for industrial EUV resist qualification and large-area nanopatterning. The designed illuminator increases the wafer-throughput and improves the imaging quality.
Blue-LIRIC in the rabbit cornea: efficacy, tissue effects, and repetition rate scaling
Authors: Huang Ruiting , Yu Dan , Savage Daniel , Wozniak Kaitlin , Zheleznyak Len , Knox Wayne H. , Huxlin Krystel R.
Published: March 2022

Laser-induced refractive index change (LIRIC) is being developed as a non-invasive way to alter optical properties of transparent, ophthalmic materials including corneas ex vivo and in vivo. This study examined the optical and biological effects of blue-LIRIC (wavelengths 400–405 nm) of ex-vivo rabbit corneas. Following LIRIC treatment at low and high repetition rates (8.3 MHz and 80 MHz, respectively), we interferometrically measured optical phase change, obtained transmission electron microscopy (TEM) micrographs, and stained histological sections with collagen hybridizing peptides (CHP) to assess the structural and organizational changes caused by LIRIC at different repetition rates. Finally, we performed power and scan speed scaling experiments at three different repetition rates (1 MHz, 8.3 MHz, and 80 MHz) to study their impact on LIRIC efficacy. Histologic co-localization of CHP and LIRIC-generated green autofluorescence signals suggested that collagen denaturation had occurred in the laser-irradiated region. TEM imaging showed different ultrastructural modifications for low and high repetition rate writing, with discrete homogenization of collagen fibrils at 80 MHz, as opposed to contiguous homogenization at 8.3 MHz. Overall, this study confirmed that LIRIC efficacy can be dramatically increased, while still avoiding tissue ablation, by lowering the repetition rate from 80 MHz to 8.3 MHz. Modeling suggests that this is due to a higher, single-pulse, energy density deposition at given laser powers during 8.3 MHz LIRIC.
Multi-scale laser speckle contrast imaging of microcirculatory vasoreactivity
Authors: Lee Blaire , Sosnovtseva Olga , Sørensen Charlotte M. , Postnov Dmitry D.
Published: March 2022

Laser speckle contrast imaging is a robust and versatile blood flow imaging tool in basic and clinical research for its relatively simple construction and ease of customization. One of its key features is the scalability of the imaged field of view. With minimal changes to the system or analysis, laser speckle contrast imaging allows for high-resolution blood flow imaging through cranial windows or low-resolution perfusion visualization of perfusion over large areas, e.g. in human skin. We further utilize this feature and introduce a multi-scale laser speckle contrast imaging system, which we apply to study vasoreactivity in renal microcirculation. We combine high resolution (small field of view) to segment blood flow in individual vessels with low resolution (large field of view) to monitor global blood flow changes across the renal surface. Furthermore, we compare their performance when analyzing blood flow dynamics potentially associated with a single nephron and show that the previously published approaches, based on low-zoom imaging alone, provide inaccurate results in such applications.
Polarization-based smoke removal method for surgical images
Authors: Wang Daqian , Qi Ji , Huang Baoru , Noble Elizabeth , Stoyanov Danail , Gao Jun , Elson Daniel S.
Published: March 2022

Smoke generated during surgery affects tissue visibility and degrades image quality, affecting surgical decisions and limiting further image processing and analysis. Polarization is a fundamental property of light and polarization-resolved imaging has been studied and applied to general visibility restoration scenarios such as for smog or mist removal or in underwater environments. However, there is no related research or application for surgical smoke removal. Due to differences between surgical smoke and general haze scenarios, we propose an alternative imaging degradation model by redefining the form of the transmission parameters. The analysis of the propagation of polarized light interacting with the mixed medium of smoke and tissue is proposed to realize polarization-based smoke removal (visibility restoration). Theoretical analysis and observation of experimental data shows that the cross-polarized channel data generated by multiple scattering is less affected by smoke compared to the co-polarized channel. The polarization difference calculation for different color channels can estimate the model transmission parameters and reconstruct the image with restored visibility. Qualitative and quantitative comparison with alternative methods show that the polarization-based image smoke-removal method can effectively reduce the degradation of biomedical images caused by surgical smoke and partially restore the original degree of polarization of the samples.
Design of an ultrabroadband infrared metamaterial absorber in the atmospheric transparent window
Authors: Li Jia , Liu Ke , Huang Yijia , Lu Xuehua , Su Yarong , Chen Weidong , Li Ling
Published: March 2022

In order to meet the demand for broadband absorbers in the infrared transparent window of the atmosphere, we designed an ultrabroadband metamaterial absorber (MA), which is composed of a germanium-zinc sulfide-chromium-zinc sulfide (Ge-ZnS-Cr-ZnS) disk periodic array and a chromium (Cr) bottom layer. In the infrared transparent window of the atmosphere, the average absorption of the MA is as high as 99.1%, and ultrabroadband near-perfect absorption is realized. Moreover, the absorber is polarization independent and insensitive to the angle of incidence. The ultrabroadband and high-absorption metamaterial absorber has broad application prospects in solar cells, photodetectors, thermophotovoltaics, and thermal emitters.
Application of a Taylor series approximation to the Debye–Wolf integral in time-domain numerical electromagnetic simulations
Authors: Mazzolani Andrea , Macdonald Callum M. , Munro Peter R. T.
Published: March 2022

Finite-difference time-domain (FDTD) and pseudospectral time-domain
(PSTD) methods are numerical electromagnetic simulation techniques
that have been employed to perform rigorous simulations of broadband
illuminations in several contexts. However, the computational cost of
calculating the incident source fields introduced into the FDTD/PSTD
grid can be considerable. In some cases, this can exceed the
computational cost of what might be considered the principal part of
the FDTD/PSTD algorithm, which calculates the spatial derivative of
fields throughout the computational grid. In this paper, we analyze an
existing method that has been used to approximate broadband
illumination, which uses knowledge of the field only at a central
frequency of the spectrum. We then present a new, to the best of our
knowledge, approximation of the broadband illumination, which is more
accurate, while remaining computationally tractable. Finally, we
present some examples to verify the accuracy and efficiency of the new
method and compare these results with the existing method.
High efficiency coupling to metal-insulator-metal plasmonic waveguides
Authors: Blau Yoav , Gilad Timor , Hanein Yael , Boag Amir , Scheuer Jacob
Published: March 2022

A periodic array of dual-Vivaldi antennas integrated with metal-insulator-metal (MIM) plasmonic waveguides was designed and investigated for its infrared light absorbance efficiency. Full-wave analysis was used to optimize MIM waveguides compatible with parallel and series connected DC leads without sacrificing radiation efficiency. Free-space to MIM waveguide in-coupling efficiency as high as 41% has been obtained in a sub-wavelength unit cell geometry at a wavelength of 1373 nm. Higher efficiency, up to 85%, is predicted with a modified design including a backplane reflector. A nanofabrication process was developed to realize test devices and far-field optical spectroscopy was used as experimental evidence for antenna-waveguide matching.
Suppression of undamped relaxation oscillation in a laser self-mixing interferometry sensing system
Authors: Liu Bin , Wang Bo , Ruan Yuxi , Yu Yanguang
Published: March 2022

Undamped relaxation oscillation (RO) in a laser self-mixing interferometry (SMI) system may occur in some common application conditions, which may impact the stable operation of the system and degrade its sensing performance. In this work, we proposed to suppress the undamped RO by controlling the system operation parameters in a laser SMI sensing system. By numerically solving the famous Lang Kobayashi equations, the stability of a laser SMI system in a 3-parameter space of external cavity length, injection current and optical feedback factor were investigated. Based on the stability analyses, we determined the system operation conditions required for suppressing the undamped RO and derived an analytical expression for describing the relationship between the operation parameters. An experimental SMI system based on a laser diode (Sanyo, DL4140-001s) was implemented and verified the suppressing method. The experimental results showed that the SMI system in a moderate feedback regime can operate in steady state without undamped RO by setting proper operation parameters. This work provides useful guidance to design a stable SMI sensing system for practical applications.
Polarization multiplexing metasurface for dual-band achromatic focusing
Authors: Zhang Haochen , Zhang Zuojun , Ma XIaoliang , Pu Mingbo , Li Xiong , Guo Yinghui , Luo Xiangang
Published: March 2022

We propose a dual-band achromatic focusing metasurface based on polarization multiplexing and dispersion engineering. An anisotropic resonant phase meta-atom is designed to realize independent nonlinear phase manipulation along the orthogonal directions. Achromatic focusing metasurface and broadband reflectarray antenna are further constructed in the microwave region with a computer-assisted particle swarm optimization algorithm. The standard deviation of focus offset at 11-16 GHz (for x-polarization) and 18-24 GHz (for y-polarization) are compressed to 19.83% and 16.60% of the dispersive metasurface, respectively. The radiation gains of the reflectarray antenna increase by an average of 19.49 dB and 15.08 dB in the broadband region compared with the bare standard rectangle waveguides. Furthermore, such an achromatic metasurface can be utilized to realize different functions with polarization selectivity and applied to other frequency ranges, which holds great promise in integrated optics.
Angle-of-arrival variability of retroreflected lasers despite atmospheric reciprocity
Authors: Walsh Shane , Frost Alex , Howard Lewis , Gozzard David , Karpathakis Skevos , Dix-Matthews Benjamin , Gravestock Charles , McCann Ayden , Schediwy Sascha
Published: March 2022

Corner cube retroreflectors are commonly used as cooperative targets in free-space laser applications. The previous literature suggests that due to path reciprocity, a retroreflected beam is self-corrected across a turbulent atmosphere and should show no angle-of-arrival variability in the near field. This is at odds with recent experiments that rely on angle-of-arrival measurements in retroreflected beams for effective tip/tilt correction. In this Letter we investigate the mechanism behind observed angle-of-arrival variability using numerical field propagation to model various transceiver and retroreflector geometries. We determine that asymmetric truncation of a curved wavefront at the retroreflector, transceiver, or both, results in a difference in tip/tilt between the transmitted and reflected wavefronts. This difference propagates as angle-of-arrival variation at the transceiver despite reciprocity, providing the error signal necessary for adaptive optics tip/tilt correction without a remote beacon.
Wavelength-stabilized tunable mode-locked thulium-doped fiber laser beyond 2 µm
Authors: Bartnick Moritz , Bharathan Gayathri , Goebel Thorsten A. , Krämer Ria G. , Nolte Stefan , Brès Camille-Sophie
Published: March 2022

We report the development of a widely tunable mode-locked thulium-doped fiber laser based on a robust chirped fiber Bragg grating (CFBG). By applying mechanical tension and compression to the CFBG, an overall tunability of 20.1 nm, spanning from 2022.1 nm to 2042.2 nm, was achieved. The observed mode-locked pulse train from this fiber laser has a repetition rate of 9.4 MHz with an average power of 12.6 dBm and a pulse duration between 9.0 ps and 12.8 ps, depending on the central wavelength. To the best of our knowledge, this is the first demonstration of a tunable mode-locked thulium-doped fiber laser operating beyond 2 µm using a CFBG as a wavelength-selective element.
Enhanced ADO-OFDM-based adaptive digital dimming VLC system
Authors: Shaalan Islam E. , Fadly Eslam M. , Aly Moustafa H.
Published: March 2022

Visible light communication (VLC) has shown significant growth in recent years. VLC simultaneously offers illumination and communication. In VLC systems, dimming control is used to handle the lighting and energy consumption constraints. In this paper, a new, to the best of our knowledge, adaptive digital dimming optical-orthogonal frequency division multiplexing (ADDO-OFDM) based on pulse width modulation is proposed to combine enhanced asymmetrically clipped DC biased optical OFDM (EADO-OFDM) and negative EADO-OFDM (ENADO-OFDM). It exploits the performance benefits of EADO-OFDM and ENADO-OFDM. The proposed ADDO-OFDM controls the dimming level in a vast range with an acceptable bit error rate with a favorable data length.
Space-variant polarization conversion with artificial birefringent metallic elements
Authors: Belle Stefan , Helfert Stefan F. , Kefer Stefan , Hellmann Ralf , Jahns Jürgen
Published: March 2022

We present an artificial birefringent space-variant polarization converter for the near infrared, λ = 1550 nm. Each hollow waveguide has a rectangular shape with lateral dimensions of 1550 nm in the x-direction and 1034 nm as the largest length in the y-direction. The whole device consists of approximately 2000 × 2500 hollow waveguides realized in a 2-µm-thick gold structure. They are separated by sidewalls with a width of less than 500 nm. By proper choice of the lateral widths of the individual holes, a pixel-wise polarization conversion of an incoming wave field is possible. By suitable choice of the fabrication parameters, a birefringent phase shift up to 2π can be achieved. Hence, the structure is able to fully convert the state of polarization, e.g., from linear to circular. For fabrication of the device, femtosecond 3D direct laser writing was combined with electroplating. Here, we describe the operation of our device as a space-variant polarization converter by measuring the angle-dependent transmitted power and by calculating the ellipticity and the phase delay dependent on position as well as the azimuth angle from the experimentally determined powers.
An estimation of the absolute number of axons indicates that human cortical areas are sparsely connected
Authors: Rosen Burke Q. , Halgren Eric
Published: March 2022

The tracts between cortical areas are conceived as playing a central role in cortical information processing, but their actual numbers have never been determined in humans. Here, we estimate the absolute number of axons linking cortical areas from a whole-cortex diffusion MRI (dMRI) connectome, calibrated using the histologically measured callosal fiber density. Median connectivity is estimated as approximately 6,200 axons between cortical areas within hemisphere and approximately 1,300 axons interhemispherically, with axons connecting functionally related areas surprisingly sparse. For example, we estimate that <5% of the axons in the trunk of the arcuate and superior longitudinal fasciculi connect Wernicke’s and Broca’s areas. These results suggest that detailed information is transmitted between cortical areas either via linkage of the dense local connections or via rare, extraordinarily privileged long-range connections.
Does plasmid-based beta-lactam resistance increase E. coli infections: Modelling addition and replacement mechanisms
Authors: Godijk Noortje G. , Bootsma Martin C. J. , van Werkhoven Henri C. , Schweitzer Valentijn A. , de Greeff Sabine C. , Schoffelen Annelot F. , Bonten Marc J. M.
Published: March 2022

Infections caused by antibiotic-resistant bacteria have become more prevalent during past decades. Yet, it is unknown whether such infections occur in addition to infections with antibiotic-susceptible bacteria, thereby increasing the incidence of infections, or whether they replace such infections, leaving the total incidence unaffected. Observational longitudinal studies cannot separate both mechanisms. Using plasmid-based beta-lactam resistant E. coli as example we applied mathematical modelling to investigate whether seven biological mechanisms would lead to replacement or addition of infections. We use a mathematical neutral null model of individuals colonized with susceptible and/or resistant E. coli, with two mechanisms implying a fitness cost, i.e., increased clearance and decreased growth of resistant strains, and five mechanisms benefitting resistance, i.e., 1) increased virulence, 2) increased transmission, 3) decreased clearance of resistant strains, 4) increased rate of horizontal plasmid transfer, and 5) increased clearance of susceptible E. coli due to antibiotics. Each mechanism is modelled separately to estimate addition to or replacement of antibiotic-susceptible infections. Fitness costs cause resistant strains to die out if other strain characteristics are maintained equal. Under the assumptions tested, increased virulence is the only mechanism that increases the total number of infections. Other benefits of resistance lead to replacement of susceptible infections without changing the total number of infections. As there is no biological evidence that plasmid-based beta-lactam resistance increases virulence, these findings suggest that the burden of disease is determined by attributable effects of resistance rather than by an increase in the number of infections.
Motor-related signals support localization invariance for stable visual perception
Authors: Benucci Andrea
Published: March 2022

Our ability to perceive a stable visual world in the presence of continuous movements of the body, head, and eyes has puzzled researchers in the neuroscience field for a long time. We reformulated this problem in the context of hierarchical convolutional neural networks (CNNs)—whose architectures have been inspired by the hierarchical signal processing of the mammalian visual system—and examined perceptual stability as an optimization process that identifies image-defining features for accurate image classification in the presence of movements. Movement signals, multiplexed with visual inputs along overlapping convolutional layers, aided classification invariance of shifted images by making the classification faster to learn and more robust relative to input noise. Classification invariance was reflected in activity manifolds associated with image categories emerging in late CNN layers and with network units acquiring movement-associated activity modulations as observed experimentally during saccadic eye movements. Our findings provide a computational framework that unifies a multitude of biological observations on perceptual stability under optimality principles for image classification in artificial neural networks.
Evolution of innate behavioral strategies through competitive population dynamics
Authors: Liang Tong , Brinkman Braden A. W.
Published: March 2022

Many organism behaviors are innate or instinctual and have been “hard-coded” through evolution. Current approaches to understanding these behaviors model evolution as an optimization problem in which the traits of organisms are assumed to optimize an objective function representing evolutionary fitness. Here, we use a mechanistic birth-death dynamics approach to study the evolution of innate behavioral strategies in a simulated population of organisms. In particular, we performed agent-based stochastic simulations and mean-field analyses of organisms exploring random environments and competing with each other to find locations with plentiful resources. We find that when organism density is low, the mean-field model allows us to derive an effective objective function, predicting how the most competitive phenotypes depend on the exploration-exploitation trade-off between the scarcity of high-resource sites and the increase in birth rate those sites offer organisms. However, increasing organism density alters the most competitive behavioral strategies and precludes the derivation of a well-defined objective function. Moreover, there exists a range of densities for which the coexistence of many phenotypes persists for evolutionarily long times.
SMetABF: A rapid algorithm for Bayesian GWAS meta-analysis with a large number of studies included
Authors: Sun Jianle , Lyu Ruiqi , Deng Luojia , Li Qianwen , Zhao Yang , Zhang Yue
Published: March 2022

Bayesian methods are widely used in the GWAS meta-analysis. But the considerable consumption in both computing time and memory space poses great challenges for large-scale meta-analyses. In this research, we propose an algorithm named SMetABF to rapidly obtain the optimal ABF in the GWAS meta-analysis, where shotgun stochastic search (SSS) is introduced to improve the Bayesian GWAS meta-analysis framework, MetABF. Simulation studies confirm that SMetABF performs well in both speed and accuracy, compared to exhaustive methods and MCMC. SMetABF is applied to real GWAS datasets to find several essential loci related to Parkinson’s disease (PD) and the results support the underlying relationship between PD and other autoimmune disorders. Developed as an R package and a web tool, SMetABF will become a useful tool to integrate different studies and identify more variants associated with complex traits.
Knowledge of Lassa fever, its prevention and control practices and their predictors among healthcare workers during an outbreak in Northern Nigeria: A multi-centre cross-sectional assessment
Authors: Wada Yusuf Hassan , Ogunyinka Ibrahim Abayomi , Yusuff Kazeem Babatunde , Ochu Chinwe Lucia , Yahaya Mohammed , Khalid Garba Mohammed , Mutalub Yahkub Babatunde , Adeniye Sulaiman Badmus
Published: March 2022

Background

The year 2020 Lassa fever (LF) outbreak had the greatest disease burden and this can place an enormous strain on the already overstretched healthcare system and can potentially increase morbidity and mortality due to infectious diseases.

Therefore, having a knowledgeable healthcare workforce with appropriate skills and competencies to prevent and manage outbreaks of a neglected infectious disease such as LF in Nigeria will potentially enhance public health. Thus, this survey assessed the level of knowledge of LF and its prevention and control (PC) measures amongst the healthcare workers (HCWs) during a LF outbreak in Katsina state, Nigeria.

Methodology/Principal findings

During this cross-sectional survey, HCWs complete a validated 29-item questionnaire comprising 18 items on the knowledge of LF and its PC measures and an item on global self-evaluation of their LF knowledge. Psychometric properties of the questionnaire were evaluated. Chi-square and binary logistic regression analyses were conducted.

Out of 435 HCWs invited, a total of 400 participated in the study (92% response rate). The majority of participants (51.8%) demonstrated inadequate LF knowledge, with 62.9% of those scoring low having a high self-perception of their LF knowledge with the global scale. This LF knowledge over-estimation was predicted by LF training status (odds ratio (OR) 2.53; 95% CI: 1.49–4.30; p = 0.001). The level of LF knowledge and its PC measures among the study participants was low (11.60±8.14, 64.4%) and predicted by participants’ LF training status (OR 2.06; 95% CI: 1.19–3.57; p = 0.009), place of work (OR 1.82; 95% CI: 1.07–3.08; p = 0.03) and their designations (OR 2.40; 95% CI: 1.10–5.22; p = 0.03).

Conclusion

The level of knowledge of LF and its PC measures among the HCWs surveyed was suboptimal and participants’ LF training status, place of work and occupational category were the significant predictors. In addition, LF knowledge overestimation on a global scale was observed among a majority of HCWs and this was also predicted by LF training status. Therefore, there is a critical need for health authorities in Nigeria to prioritize continuous on-the-job training of HCWs on priority neglected tropical diseases such as Lassa fever.
Reasons for non-attendance to cervical cancer screening and acceptability of HPV self-sampling among Bruneian women: A cross-sectional study
Authors: Chaw Liling , Lee Shirley H. F. , Ja’afar Nurul Iffah Hazwani , Lim Edwin , Sharbawi Roslin
Published: March 2022

Objective

Uptake for cervical cancer screening remains well below the 80% target as recommended by Brunei’s National Cervical Cancer Prevention and Control plan. We conducted a pilot study to determine the reasons for non-attendance and explore their acceptance of human papillomavirus (HPV) self-sampling as an alternative to the Pap test.

Methods

A cross-sectional study was conducted at a primary healthcare center in Brunei, from January to December 2019. We recruited screening non-attendees, defined as women who were eligible for Pap test but who either never, or did not have one within the recommended screening interval of 3 years. This recruitment was done conveniently among women attending outpatient care and/or child health services at the primary healthcare center. Participants were first asked to complete a self-administered paper-based questionnaire on their reasons for screening non-attendance, and then invited for HPV self-sampling. Among those who agreed to participate in HPV self-sampling, they were asked to complete a second questionnaire on the self-sampling procedure and their samples were tested for high-risk HPV (hr-HPV). Results were analyzed using descriptive and inferential statistics.

Result

We enrolled 174 screening non-attendees, out of which 97 (55.7%) also participated in HPV self-sampling. The main reasons for not attending Pap test screening were fear of bad results (16.1%, n = 28); embarrassment (14.9%, n = 26) and lack of time due to home commitments (10.3%, n = 18). When compared to those who agreed to participate in HPV self-sampling, those who declined were significantly older (p = 0.002) and less likely to agree that they are susceptible to cervical cancer (p = 0.023). They preferred to receive Pap test-related information from healthcare workers (59.0%, n = 155), social messaging platforms (28.7%, n = 51) and social media (26.4%, n = 47). HPV self-sampling kits were positively received among the 97 participants, where > 90% agreed on its ease and convenience. Nine (9.3%) tested positive for hr-HPV, out of which eight were non-16/18 HPV genotypes.

Conclusion

Our findings suggest that promoting awareness on cervical cancer, clarifying any misconceptions of Pap test results, and highlighting that the disease is preventable and that early detection through screening can facilitate successful treatment would help increase screening uptake among Bruneian non-attendees. Response to HPV self-sampling was highly positive, suggesting the possibility of implementing this strategy in the local setting. Our high detection of non-16/18 HPV genotypes suggest high prevalence of other hr-HPV genotypes in Brunei. Larger studies should be conducted to further validate our findings.
Be(e)coming pollinators: Beekeeping and perceptions of environmentalism in Massachusetts
Authors: DiDonato Sandra , Gareau Brian J.
Published: March 2022

In an era of mass extinction and biodiversity crisis, it is increasingly crucial to cultivate more just and inclusive multispecies futures. As mitigation and adaption efforts are formed in response to these crises, just transitions forward require intentional consideration of the hybrid entanglement of humans, human societies, and wider landscapes. We thus apply a critical hybridity framework to examine the entanglement of the pollinator crisis with the cultural and agricultural practice of hobbyist beekeeping. We draw on ethnographic engagements with Massachusetts beekeepers and find apiculture to be widely understood as a form of environmentalism—including as both a mitigation to and adaptation for the pollinator crisis. Illustrating how power-laden socioecological negotiations shape and reshape regional environments, we then discuss how this narrative relies on the capitalistic and instrumental logics characteristic of Capitalocene environmentalisms. These rationalities, which obscure the hybridity of landscapes, consequently increase the likelihood of problematic unintended consequences. Also present, however, is a deeper engagement with hybrid perspectives, with some beekeepers even offering pathways toward inclusive solutions. We conclude that if more just and biodiverse futures are to be realized, beekeeping communities must foster increasingly hybrid visions of apiculture as situated within socioecological and contested landscapes.
Preliminary application of native Nephila edulis spider silk and fibrin implant causes granulomatous foreign body reaction in vivo in rat’s spinal cord
Authors: Koop Felix , Strauß Sarah , Peck Claas-Tido , Aper Thomas , Wilhelmi Mathias , Hartmann Christian , Hegermann Jan , Schipke Julia , Vogt Peter M. , Bucan Vesna
Published: March 2022

After spinal cord injury, gliomesenchymal scaring inhibits axonal regeneration as a physical barrier. In peripheral nerve injuries, native spider silk was shown to be an effective scaffold to facilitate axonal re-growth and nerve regeneration. This study tested a two-composite scaffold made of longitudinally oriented native spider silk containing a Haemocomplettan fibrin sheath to bridge lesions in the spinal cord and enhance axonal sprouting. In vitro cultivation of neuronal cells on spider silk and fibrin revealed no cytotoxicity of the scaffold components. When spinal cord tissue was cultured on spider silk that was reeled around a metal frame, migration of different cell types, including neurons and neural stem cells, was observed. The scaffold was implanted into spinal cord lesions of four Wistar rats to evaluate the physical stress caused on the animals and examine the bridging potential for axonal sprouting and spinal cord regeneration. However, the implantation in-vivo resulted in a granulomatous foreign body reaction. Spider silk might be responsible for the strong immune response. Thus, the immune response to native spider silk seems to be stronger in the central nervous system than it is known to be in the peripheral body complicating the application of native spider silk in spinal cord injury treatment.
Serum albumin and FT3/FT4 ratio as additional co-morbidity parameters to predict mortality as a new approach: The Haseki Scoring Index (updated Charlson Comorbidity Index)
Authors: Cavusoglu Turker Betul , Turker Fatih , Ahbab Suleyman , Hoca Emre , Tahmaz Meryem , Ataoğlu Hayriye Esra
Published: March 2022

Background

Charlson Comorbidity Index (CCI) is the common and valid method to predict mortality by classifying comorbidities such as cardiovascular, metabolic, renal, hepatic, pulmonary diseases, and malignancy. Novel risk factors are not included in the Charlson Comorbidity Index, such as thyroid hormone index (FT3/FT4 ratio) and serum albumin levels. In the present study, we aimed to assess whether the thyroid hormone index and albumin are useful clinical parameters in short and long-term mortality.

Methods

In the retrospective cohort study with a 5 year follow up, the data of 1292 patients who were hospitalized between January 1st–June 30th of 2014 were examined. Three months mortality as short term and 5-year mortality as long term were evaluated.

Results

Three months and 5 years mortality rates for 1064 patients were analyzed. We showed that hypoalbuminemia and thyroid hormone index had statistically significant effects on short and long-term mortality. According to ROC analysis it was demonstrated that the scoring system including biochemical parameters such as thyroid hormone index and serum albumin level was more significant for 3-month mortality. In addition, both scoring systems are equal in demonstrating long-term mortality.

Conclusion

Thyroid hormone index and albumin could improve the prognostic performance of the original Charlson Comorbidity Index in short term mortality. The combined score may offer improvements in comorbidity summarization over existing scores.
Effects of equine SALSA on neutrophil phagocytosis and macrophage cytokine production
Authors: Lee Gary Kwok Cheong , Kang Heng , Beeler-Marfisi Janet , Sears William , Lillie Brandon N. , Bienzle Dorothee
Published: March 2022

Salivary scavenger and agglutinin (SALSA) is a secreted protein with various immunomodulatory roles. In humans, the protein agglutinates and inactivates microorganisms, and inhibits the release of pro-inflammatory cytokines. Saliva, which is rich in SALSA, accelerates bacterial phagocytosis, but SALSA’s contribution is unclear. In horses, the functions of SALSA in inflammation remain undetermined, so they were investigated through phagocytosis and cytokine assays. Equine SALSA was purified from duodenal tissue, which contains abundant SALSA. To assess phagocytosis, fluorescently-labelled bacteria were incubated with 20, 10, 5, or 2.5 μg/mL of SALSA or phosphate buffered saline (PBS), and then incubated at 37°C or on ice with whole blood from seven healthy horses. Fluorescence was measured by gating on neutrophils using a flow cytometer, and compared between groups. To assess effects on cytokine production, alveolar macrophages were isolated from bronchoalveolar lavage fluid of five healthy horses and cultured in serum-free media for 24 hours with different concentrations of SALSA plus 1 μg/mL lipopolysaccharide (LPS), only LPS, or only media. Cytokines were measured in supernatant using an equine-specific multiplex bead immunoassay. There was significantly greater phagocytosis in samples incubated at 37°C compared to incubation on ice. Samples incubated with 20 μg/mL of SALSA at 37°C had less phagocytosis compared to samples with 10 or 2.5 μg/mL SALSA, or PBS. Alveolar macrophages incubated with SALSA plus LPS released significantly less CXC motif chemokine ligand 1, interleukin-8, interleukin-10, and tumor necrosis factor α, and more granulocyte colony stimulating factor (G-CSF), compared to macrophages incubated with LPS alone. These findings indicate anti-inflammatory effects, which may be due to interference with toll-like receptor 4 recognition of LPS or downstream signaling. Increase in G-CSF following incubation with SALSA suggests a novel mechanism for immunoregulation of alveolar macrophages by SALSA, addressing a knowledge gap regarding its functions in horses.