bluuebunny/crossref_metadata_2025 huggingface dataset:
High-Radiance Upconversion Luminescence from Lanthanide-Doped Nanoparticles-Engineered Metasurface Supporting Bound States in the Continuum
Authors: Schiattarella Chiara , Romano Silvia , Sirleto Luigi , Mocella Vito , Rendina Ivo , Lanzio Vittorino , Riminucci Fabrizio , Cabrini Stefano , Liang Liangliang , Liu Xiaogang , Zito Gianluigi
Published: November 2022

A giant enhancement of upconversion luminescence (UCPL) from an all-dielectric metasurface supporting bound states in the continuum (BICs) engineered with lanthanide-doped nanocrystals is herein demonstrated. The strong-coupling mechanism occurring at the edge of the photonic superstructure leads to an UCPL radiance enhancement of ~108.
Dynamics of dissipative Kerr cavity solitons in the presence of rapid parameter inhomogeneities
Authors: Todd Caleb , Coen Stéphane , Murdoch Stuart G. , Oppo Gian-Luca , Erkintalo Miro
Published: November 2022

We explore the dynamics of temporal cavity solitons under rapid parameter inhomogeneities where usual linear approximations become invalid. We show that a more general theoretical treatment allows for the accurate prediction of soliton motion.
Phase-matching-free intracavity second harmonic generation from a WSe2 monolayer in a passively mode-locked picosecond fiber laser
Authors: Xu Guangpeng , Carvalho Jeffrey , Wijesundara Chiran , Kilinc Muhammed , Cheney Alec , Neureuter Christian , Tarasek Steven , Thomay Tim
Published: November 2022

Phase-matching-free SHG is observed from a monolayer WSe2 placed in a Yb3+ doped picosecond fiber oscillator. The mode-locking and laser output of the fiber oscillator are unaffected. This enables applications in self-referencing f-2f frequency combs.
Taming light bullets in the hollow-fiber compressor
Authors: Steinmeyer Günter , Nagy Tamas , Babushkin Ihar , Mei Chao
Published: November 2022

A completely analytical approach is presented that provides deep insight into the pulse formation processes in a hollow fiber compressor by disentangling spatial soliton dynamics.
Farey Tree and Devil’s Staircase of a Breather Mode-Locked Fibre Laser
Authors: Wu X. , Zhang Y. , Peng J. , Boscolo S. , Finot C. , Zeng H.
Published: November 2022

We demonstrate frequency locking at Farey fractions of breathing solitons in an ultrafast fibre laser. The ratios of the breathing frequency to the cavity-repetition frequency display the devil staircase’s structure with a 0.906 fractal dimension.
Nonlinear Saturable Absorption Threshold for Stable Mode-Locking in Different Dispersion Regions
Authors: Liu Bowen , Yamashita Shinji , Set Sze Yun
Published: November 2022

Nonlinear saturable absorption threshold of a fast saturable absorber for stable mode-locking is numerically investigated, which reveals distinct patterns within different dispersion managements. Meanwhile, the impacts of saturable absorber parameters on mode-locking dynamics are analyzed.
Walk-off Solitons and Single-mode Spatiotemporal Attractor in Multimode Fibers
Authors: Zitelli Mario , Sun Yifan , Ferraro Mario , Mangini Fabio , Parra-Rivas Pedro , Wabnitz Stefan
Published: November 2022

Optical solitons in multimode fibers exhibit complex dynamics which have no counterpart in the singlemode case. Experiments and simulations reveal the emergence of new phenomena such as walk-off solitons, dynamical attractors and mode transformation collisions.
Machine learning optimization of supercontinuum properties towards multiphoton microscopy
Authors: Hoang Van Thuy , Boussafa Yassin , Sader Lynn , Février Sébastien , Couderc Vincent , Wetzel Benjamin
Published: November 2022

We numerically study how the suitable adjustment of femtosecond pulse patterns in combination with machine learning can be leveraged to maximize the output spectral intensities and temporal waveforms at wavelengths relevant for multi-photon imaging.
Non-Linearity and Spatiotemporal Complexity in Phase-Conjugated Optical-Feedback Systems
Authors: Malica Tushar , Bouchez Guillaume , Wolfersberger Delphine , Sciamanna Marc
Published: November 2022

Novel spatiotemporally complex nonlinear dynamics observed in a phase-conjugate optical feedback system are experimentally captured and classified using chaos bandwidth (~30 GHz), quantifying complexity via permutation entropy (> 0.9), and real-time frequency and temporal analyses.
Optical Properties and Nonlinear Optical Response of Zirconium-doped Indium Oxide in the Epsilon-Near-Zero Region
Authors: Ghobadi H. , Smirnov Y. , Korterik J. P. , Alvarez-Chavez J. A. , Offerhaus H. L. , Morales-Masis M. , De Leon I.
Published: November 2022

We report the linear and nonlinear optical properties of Zirconium-doped Indium Oxide film in the near-zero permittivity spectral region. We observe a relatively broadband nonlinear response, which could be due to a gradient permittivity.
From Quantum to Classical Nonlinear Dynamics in the Unbalanced Dicke Model
Authors: Stitely Kevin C. , Giraldo Andrus , Krauskopf Bernd , Parkins Scott
Published: November 2022

We investigate the appearance of classical nonlinear dynamics in the non-equilibrium quantum phase transition to superradiance in the unbalanced Dicke model. Specifically, we uncover a variety of dynamical behavior, including hysteresis, superradiant oscillations, and chaos.
3 × 1 fiber signal combiner with high beam quality Gaussian-like beam for a 10kW-level fiber laser
Authors: Zhou Yanyan , Yang Aibi , Yang Guanghua , Qiu Qiang , Zhang Xu , Zhang Zhilun , Xing Yinbin , Peng Jinggang , Li HaiQing , Chu Yingbo , Li Jinyan , Dai Nengli
Published: November 2022

We present the design and fabrication of a 3 × 1 signal combiner with high beam quality based on supermode theory. For improving beam quality, the fiber with core diameter of 34 µm and numerical aperture of 0.11 is first chosen as the output fiber. An 8.89 kW output laser with a power transmission efficiency of 97.2% and a low temperature rise coefficient of 3.5 °C/ kW at >8 kW is obtained when the combiner launched by three Yb-doped fiber lasers. In addition, the energy density distribution of the output beam is Gaussian-like and M2 factor is 2.32, which is the best beam quality compared with the presented signal combiners for high power laser to the best of our knowledge.
Generalized Newton’s rings with vortex beams
Authors: Yan Jiadian , Yao Jun , Liu Yidong , Yang Yuanjie
Published: November 2022

The Newton’s rings are interference patterns with concentric rings, and Newton’s rings experiment is one of the most famous classic optics experiments. Here, we show that if we use a vortex beam, we can obtain generalized Newton’s rings. Unlike traditional Newton’s rings, the generalized ones are no longer concentric rings but spiral arms, and fork-shaped dislocations appear in spiral arms. More interesting, we reveal that both the number of spiral arms and the number of fork-shaped dislocations are equal to the value of topological charge of incident vortex beams. Our theoretical results are demonstrated experimentally. This novel interference pattern can be used for measuring the topological charge of vortex beams.
Empirical and Theoretical study of the Thermal Performance of High Power UVC LEDs
Authors: Fredes Pablo , Raff Ulrich , Soto Cristian , Sharma Pratibha
Published: November 2022

UVC LEDs exhibit high junction temperature (T
J
) and voltage sensitivity, which influences their radiant power and lifetimes. This study of 275nm, 3-PAD UVC LEDs can be useful to estimate T
J
and emphasize the need for optimal thermal management.
Self-oscillating Circuits from Electrochromic Devices and Solar Cells
Authors: Zheng Jian-Yao , Rezaei Nasim , Saive Rebecca
Published: November 2022

By combing an electrochromic device and a solar cell, we successfully built a self-oscillating circuit. We can extract the alternating output from such device, facilitating its future applications.
Soft Microstructured Optical Fibers via Thermal Drawing
Authors: Banerjee Hritwick , Bartolomei Nicola , Sorin Fabien
Published: November 2022

The preform-to-fiber thermal drawing of thermoplastic elastomers enables the fabrication of soft multi-material optical fibers with complex architectures. It offers unprecedented opportunities to realize complex soft optical fibers for transmission and sensing.
X-ray tomography for the refractive index profiling of standard glass optical fibers
Authors: Crocco Maria Caterina , Ferraro Mario , Mangini Fabio , Jonard Maxime , Sangiovanni Francesco , Zitelli Mario , Filosa Raffaele , Beltrano Joseph J. , De Luca Antonio , Barberi Riccardo C. , Agostino Raffaele Giuseppe , Couderc Vincent , Wabnitz Stefan , Formoso Vincenzo
Published: November 2022

By exploiting the absorption contrast provided by the doping of silica, we demonstrate that X-ray microtomography is capable of retrieving the 3D spatial profile of standard multimode glass optical fibers.
Fabricating Thin Membraned Anti-Resonant Hollow-Core Fibre for Broadband UV-visible Light Guidance
Authors: Jackson Gregory , Davidson Ian A , Bradley Thomas D , Jasion Gregory T , Richardson David J , Poletti Francesco
Published: November 2022

We demonstrate a fabrication technique enabling long lengths (>2km) of hollow-core anti-resonant fibres (HC-ARFs) with thin-membranes (<200nm), not otherwise achievable with conventional two-stage stack-and-draw processes. We produce 348m fibre guiding 370-1050nm in its fundamental widow.
Enhanced OAM Mode Purity in Ring-core Optical Fiber with Graded-index Profile
Authors: Liu Yuanpeng , Wang Yingning , Geng Wenpu , Zhao Wenqian , Pan Zhongqi , Yue Yang
Published: November 2022

OAM mode purity in graded-index ring-core fiber with different shape factors is investigated. The purity of OAM1,1 is significantly increased from 86.48% to 94.43% by changing the ring-core fiber from step-index to parabolic graded-index profile.
Far-detuned Four-wave Mixing Frequency Conversion Based on Special Dispersion Controlled Highly Nonlinear Fiber
Authors: Ahmedou Sidi-Ely , Dauliat Romain , Parriaux Alexandre , Malfondet Alix , Millot Guy , Labonte Laurent , Tanzilli Sébastien , Dalidet Romain , Delagnes Jean-Christophe , Roy Philippe , Jamier Raphael
Published: November 2022

We report on the conception, fabrication and characterization of a new concept of optical fiber enabling a precise control of the ratio between the 2nd and 4th-order chromatic dispersion (respectively β2 and β4) at 1.55 μm which is primordial for ensuring an effective frequency conversion by far-detuned Four-Wave-Mixing (FWM). Experimental demonstration relying on an atypical discretized highly nonlinear fiber (D-HNLF) is shown and discussed.
4D Geometric Shell Shaping with Applications to 400ZR
Authors: Goossens Sebastiaan , Gültekin Yunus Can , Vassilieva Olga , Kim Inwoong , Palacharla Paparao , Okonkwo Chigo , Alvarado Alex
Published: November 2022

Geometric shell shaping is introduced and evaluated for reach increase and nonlinearity tolerance in terms of MI against PM-16QAM and PS-PM-16QAM in a 400ZR compatible transmission setup.
Equalization Noise Reduction Through Constellation Distortion in Coherent Systems
Authors: Berikaa Essam , Alam Md Samiul , Hu Yixiang , Lessard Stéphane , Plant David V.
Published: November 2022

We propose a constellation distortion approach that mitigates equalization-enhanced noise in coherent systems. Experimental data show a 0.5 dB OSNR improvement, allowing the transmission of net 843 Gbps 32QAM using an all-silicon modulator below HD-FEC.
Transmission Experiments and Modeling of Subsea Fiber Links with Terrestrial Backhaul Segments
Authors: Downie John D. , Liang Xiaojun , Hurley Jason
Published: November 2022

We investigate transmission performance of trans-oceanic subsea links with terrestrial backhaul segments experimentally and in modeling. We estimate total channel capacity and quantify differences between terrestrial fiber types and for varying terrestrial lengths.
Linear complexity Volterra-based equalization and predistortion in LED communications
Authors: Stepniak Grzegorz
Published: November 2022

In this contribution, we postulate that the nonlinear distortion in LED based communications can be mitigated by both both predistorters and equalizers having linear complexity. Efficiency of different structures is compared.
Emerging THz Applications Enabled by Double-RTD Transmitters
Authors: Nobrega Rafael , Sanches Anderson , Loiola Murilo , Haxha Shyqyri , Jurado-Navas Antonio , Raddo Thiago
Published: November 2022

This work proposes transmitters based on double-RTD operating in the Y-band for emerging THz applications. The new transmitter provides an output power ~1.1 mW, channel capacity ~0.11 Tb/s and ~46-meter link reach at 338 GHz.
Neural Network Based Black-box Estimator of Mutual Information
Authors: Eriksson Tobias A. , Villafani Diego , Åhlfeldt Henrik , Schmalen Laurent
Published: November 2022

We show that neural networks with softmax outputs are capable of estimating a lower bound on the mutual information of memoryless communication channels without prior knowledge of the channel properties.
Multi-channel optical neuromorphic processing
Authors: Sorokina Mariia
Published: November 2022

We present the first optical neuromorphic processor for multi-channel signals. The design is demonstrated on wavelength-division multiplexed (WDM) signals. The technology is also suitable for processing orthogonal frequency-division multiplexed (OFDM) signals with applications in communications.
Demonstration of Si-PIC Based Endless Adaptive Polarization Control for PMC-SH DCIs
Authors: Sidhique Aboobackkar , Chugh Shivangi , Singh Utsav , Naaz Sana , Singh Anamika , Gupta Shalabh
Published: November 2022

We demonstrate Si-PIC based endless adaptive polarization control in a polarization multiplexed carrier based self-homodyne (PMC-SH) link. This proof-of-concept demonstration paves way for the use of PMC-SH link for 800 Gbps and beyond DCIs.
Organic Molecules for Quantum Communication
Authors: Colautti M. , Murtaza G. , Hilke M. , Lombardi P. , Cataliotti F. S. , Zavatta A. , Bacco D. , Toninelli C.
Published: November 2022

We demonstrate a quantum key distribution testbed exploiting a molecule-based single-photon source operating at room-temperature. With an estimated secret key rate of 0.5Mbps, we set the ground for room-temperature deterministic emitters for quantum communication protocols.
Reproducibility efforts as a teaching tool: A pilot study
Authors: Karathanasis Nestoras , Hwang Daniel , Heng Vibol , Abhimannyu Rimal , Slogoff-Sevilla Phillip , Buchel Gina , Frisbie Victoria , Li Peiyao , Kryoneriti Dafni , Rigoutsos Isidore
Published: November 2022

The “replication crisis” is a methodological problem in which many scientific research findings have been difficult or impossible to replicate. Because the reproducibility of empirical results is an essential aspect of the scientific method, such failures endanger the credibility of theories based on them and possibly significant portions of scientific knowledge. An instance of the replication crisis, analytic replication, pertains to reproducing published results through computational reanalysis of the authors’ original data. However, direct replications are costly, time-consuming, and unrewarded in today’s publishing standards. We propose that bioinformatics and computational biology students replicate recent discoveries as part of their curriculum. Considering the above, we performed a pilot study in one of the graduate-level courses we developed and taught at our University. The course is entitled Intro to R Programming and is meant for students in our Master’s and PhD programs who have little to no programming skills. As the course emphasized real-world data analysis, we thought it would be an appropriate setting to carry out this study. The primary objective was to expose the students to real biological data analysis problems. These include locating and downloading the needed datasets, understanding any underlying conventions and annotations, understanding the analytical methods, and regenerating multiple graphs from their assigned article. The secondary goal was to determine whether the assigned articles contained sufficient information for a graduate-level student to replicate its figures. Overall, the students successfully reproduced 39% of the figures. The main obstacles were the need for more advanced programming skills and the incomplete documentation of the applied methods. Students were engaged, enthusiastic, and focused throughout the semester. We believe that this teaching approach will allow students to make fundamental scientific contributions under appropriate supervision. It will teach them about the scientific process, the importance of reporting standards, and the importance of openness.
Skilled birth care uptake among women from socially disadvantaged minorities in the Kambata-Tambaro Zone, Southern Ethiopia
Authors: Alemu Abebe , Assefa Biruk , Ahmed Ritbano , Mosa Hassen , Gebeyehu Negesso
Published: November 2022

Globally in 2019, it was reported that 295,000 women die during pregnancy and childbirth every year. In Ethiopia, skilled birth care service uptake was low. Thus, the study aimed to assess the magnitude of skilled birth care uptake, and associated factors among women from socially disadvantaged minorities in the Kambeta-Temabaro Zone, Southern Ethiopia. A multistage sampling procedure was employed to enroll 521 study participants. Data were entered using EPI-INFO and SPSS-21 for analysis. Bivariate and multivariate analysis was done and the degree of association was assessed using odds ratios with a 95% confidence interval and variables with p values <0.05 were declared statistically significant. The magnitude of skilled birth care service uptake among women from socially disadvantaged minorities was 19%. Maternal education, occupation, awareness of birth care, pregnancy plan, number of births, mothers’ lifestyle, and social subordination were significantly associated with skilled birth care service uptake in the study area. Thus, awareness creation on skilled birth, improving access to education for women, increasing the employability of women, and conducting community forums to avoid social discrimination against minorities are highly recommended.
Hospital admissions with influenza and impact of age and comorbidities on severe clinical outcomes in Brazil and Mexico
Authors: El Guerche-Séblain Clotilde , Etcheto Adrien , Parmentier Frédéric , Afshar Mohammad , E. Macias Alejandro , Puentes Esteban , Gresset-Bourgeois Viviane , Akcay Meral , Petitjean Audrey , Coudeville Laurent
Published: November 2022

Background

The risk of hospitalization or death after influenza infection is higher at the extremes of age and in individuals with comorbidities. We estimated the number of hospitalizations with influenza and characterized the cumulative risk of comorbidities and age on severe outcomes in Mexico and Brazil.

Methods

We used national hospital discharge data from Brazil (SIH/SUS) from 2010–2018 and Mexico (SAEH) from 2010–2017 to estimate the number of influenza admissions using ICD-10 discharge codes, stratified by age (0–4, 5–17, 18–49, 50–64, and ≥65 years). Duration of hospital stay, admission to the intensive care unit (ICU), and in-hospital case fatality rates (CFRs) defined the severe outcomes. Rates were compared between patients with or without pre-specified comorbidities and by age.

Results

A total of 327,572 admissions with influenza were recorded in Brazil and 20,613 in Mexico, with peaks period most years. In Brazil, the median hospital stay duration was 3.0 days (interquartile range, 2.0–5.0), ICU admission rate was 3.3% (95% CI, 3.2–3.3%), and in-hospital CFR was 4.6% (95% CI, 4.5–4.7). In Mexico, the median duration of stay was 5.0 days (interquartile range, 3.0–7.0), ICU admission rate was 1.8% (95% CI, 1.6–2.0%), and in-hospital CFR was 6.9% (95% CI, 6.5–7.2). In Brazil, ICU admission and in-hospital CFR were higher in adults aged ≥50 years and increased in the presence of comorbidities, especially cardiovascular disease. In Mexico, comorbidities increased the risk of ICU admission by 1.9 (95% CI, 1.0–3.5) and in-hospital CFR by 13.9 (95% CI, 8.4–22.9) in children 0–4 years.

Conclusion

The SIH/SUS and SAEH databases can be used to estimate hospital admissions with influenza, and the disease severity. Age and comorbidities, especially cardiovascular disease, are cumulatively associated with more severe outcomes, with differences between countries. This association should be further analyzed in prospective surveillance studies designed to support influenza vaccination strategy decisions.
Modulated sampled-data consensus for networked Euler-Lagrange systems with differentiable pulse function
Authors: Sun Yongzhi , Wang Yilin , Li Yang , Xiang Xinjian
Published: November 2022

This paper is concerned with the sampled-data consensus of networked Euler-Lagrange systems. The Euler-Lagrange system has enormous advantages in analyzing and designing dynamical systems. Yet, some problems arise in the Euler-Lagrange equation-based control laws when they contain sampled-data feedbacks. The control law differentiates the discontinuous sampled-data signals to generate its control input. In this process, infinities in the control inputs are generated inevitably. The main goal of this work is to eliminate these infinities and make the control inputs applicable. To reach this goal, a class of differentiable pulse functions is designed for the controllers. The pulse functions work as multipliers on the sampled-data signals to make them differentiable, hence avoid the infinities. A new consensus condition compatible with the pulse function is also obtained through rigorous consensus analysis. The condition is proved to be less conservative compared with that of the existing method. Finally, numerical examples are given to illustrate the findings and theoretical results.
The most recent baltic sea marine hunter-gatherers? The buried individual of grave IB3 in the Suutarinniemi cemetery, Finland
Authors: Lahtinen Maria , Hakamäki Ville , Kuusela Jari-Matti
Published: November 2022

Most European hunter-gatherers slowly assimilated into farming communities during the Neolithic period. In the north these groups persisted far longer. In this paper, we present evidence from what may be one of the most recent non-agricultural sites in the region, where a marine hunter-gatherer lifestyle may have continued until as late as the 15th–16th centuries AD. The isotope composition of incremental dental analysis suggests a significant, long-term dependence on seals. This indicates that vestiges of this means of subsistence might have been present in Europe for much longer than previously thought.
Human lipoproteins comprise at least 12 different classes that are lognormally distributed
Authors: Konishi Tomokazu , Fujiwara Risako , Saito Tadaaki , Satou Nozomi , Hayashi Yurie , Crofts Naoko , Iwasaki Ikuko , Abe Yoshihisa , Kawata Shinpei , Ishikawa Tatsuya
Published: November 2022

This study presents the results of HPLC, a gentler and rapid separation method in comparison with the conventional ultracentrifugation, for 55 human serum samples. The elution patterns were analysed parametrically, and the attribute of each class was confirmed biochemically. Human samples contained 12 classes of lipoproteins, each of which may consist primarily of proteins. There are three classes of VLDLs. The level of each class was distributed lognormally, and the standard amount and the 95% range were estimated. Some lipoprotein classes with a narrow range could become ideal indicators of specific diseases. This lognormal character suggests that the levels are controlled by the synergy of multiple factors; multiple undesirable lifestyle habits may drastically increase the levels of specific lipoprotein classes. Lipoproteins in medical samples have been measured by enzymatic methods that coincide with conventional ultracentrifugation; however, the high gravity and time required for ultracentrifugation can cause sample degradation. Actually, the enzymatic methods measured the levels of several mixed classes. The targets of enzymatic methods have to be revised.
Vaccines and more: The response of Dark Web marketplaces to the ongoing COVID-19 pandemic
Authors: Bracci Alberto , Nadini Matthieu , Aliapoulios Maxwell , McCoy Damon , Gray Ian , Teytelboym Alexander , Gallo Angela , Baronchelli Andrea
Published: November 2022

Early analyses revealed that dark web marketplaces (DWMs) started offering COVID-19 related products (e.g., masks and COVID-19 tests) as soon as the COVID-19 pandemic started, when these goods were in shortage in the traditional economy. Here, we broaden the scope and depth of previous investigations by considering how DWMs responded to an ongoing pandemic after the initial shock. Our dataset contains listings from 194 DWMs collected until July 2021. We start by focusing on vaccines. We find 248 listings offering approved vaccines, like Pfizer/BioNTech and AstraZeneca, as well as vendors offering fabricated proofs of vaccination and COVID-19 passports. Then, we consider COVID-19 related products. We show that, as the regular economy has become able to satisfy the demand of these goods, DWMs have decreased their offer. Next, we analyse the profile of vendors of COVID-19 related products and vaccines. We find that most of them are specialized in a single type of listings and are willing to ship worldwide. Finally, we consider a broader set of listings mentioning COVID-19, in order to assess the general impact of the pandemic on the broader activity of DWMs. Among 10,330 such listings, we show that recreational drugs are the most affected among traditional DWMs product, with COVID-19 mentions steadily increasing since March 2020. We anticipate that our results will be of interest to researchers, practitioners, and law enforcement agencies focused on the study and safeguard of public health.
Hyperbaric oxygen protects HT22 cells and PC12 cells from damage caused by oxygen-glucose deprivation/reperfusion via the inhibition of Nrf2/System Xc-/GPX4 axis-mediated ferroptosis
Authors: Chen Chunxia , Chen Wan , Zhou Xing , Li Yaoxuan , Pan Xiaorong , Chen Xiaoyu
Published: November 2022

This study was to investigate the protective effect of hyperbaric oxygen (HBO) on HT22 and PC12 cell damage caused by oxygen-glucose deprivation/reperfusion-induced ferroptosis. A 2-h oxygen-glucose deprivation and 24-h reperfusion model on HT22 and PC12 cells was used to simulate cerebral ischemia-reperfusion injury. Cell viabilities were detected by Cell Counting Kit-8 (CCK-8) method. The levels of reactive oxygen species (ROS) and lipid reactive oxygen species (Lipid ROS) were detected by fluorescent probes Dihydroethidium (DHE) and C11 BODIPY 581/591. Iron Colorimetric Assay Kit, malondialdehyde (MDA) and glutathione (GSH) activity assay kits were used to detect intracellular iron ion, MDA and GSHcontent. Cell ferroptosis-related ultrastructures were visualized using transmission electron microscopy (TEM). Furthermore, PCR and Western blot analyses were used to detect the expressions of ferroptosis-related genes and proteins. After receiving oxygen-glucose deprivation/reperfusion, the viabilities of HT22 and PC12 cells were significantly decreased; ROS, Lipid ROS, iron ions and MDA accumulation occurred in the cells; GSH contents decreased; TEM showed that cells were ruptured and blebbed, mitochondria atrophied and became smaller, mitochondrial ridges were reduced or even disappeared, and apoptotic bodies appeared. And the expressions of Nrf2, SLC7A11 and GPX4 genes were reduced; the expressions of p-Nrf2/Nrf2, xCT and GPX4 proteins were reduced. Notably, these parameters were significantly reversed by HBO, indicating that HBO can protect HT22 cells and PC12 cells from damage caused by oxygen-glucosedeprivation/reperfusion via the inhibition of Nrf2/System Xc-/GPX4 axis-mediated ferroptosis.
An analytical solution to ecosystem-based FMSY using trophic transfer efficiency of prey consumption to predator biological production
Authors: Hodgson Bruce R.
Published: November 2022

A theoretical basis for Ecosystem-based Fisheries Management (EBFM) was derived for pelagic fish by applying marine ecology theory of analytical relationships of predator-prey biological production transfers between trophic levels to FAO guidelines for an ecosystem approach to fisheries. The aim is to describe a simple method for data-limited fisheries to estimate ecosystem-based FMSY and how EBFM modellers could mimic the way natural fish communities function for maintaining ecological processes of biological production, biomass and ecosystem stability. Ecosystem stability (ES) FMSY were estimated by proportion of biological production allocated to predators, giving ESFMSY of 0.23 for small pelagic and 0.27 for pelagic finfish, prioritising ecosystem over economics. To maintain both stability and biomass (SB) a full pelagic EBFM SBFMSY of about 0.08 was obtained for both small pelagic and pelagic finfish, having mostly ecosystem considerations. As the FMSY are single-species averages of catchable species targeted in a specific trophic level, multispecies fishing mortalities were proportioned by the biological production of each species in the trophic level. This way catches for each species are consistent with the average ecosystem FMSY for a trophic level. The theoretical estimates gave similar results to other fisheries for sustainable fish catches that maintain the fishery ecosystem processes. They were also tested using six tropical Ecopath Models and showed the effects of imposing commercial fishing mortalities on predominantly EBFM conditions. The ecosystem stability ESFMSY is suggested to be investigated for sustainable fish catches and the full EBFM SBFMSY for protected areas or recovery of heavily depleted stocks.
Factors associated with COVID-19 knowledge among Ghanaians: A national survey
Authors: Kwabla Mavis Pearl , Nyasordzi Juliana , Kye-Duodu Gideon , Ananga Mark Kwame , Amenuvegbe Gregory Kofi , Otoo Joseph , Nuertey Dominic Demateh , Mensah Ebenezer Kofi , Asante-Afari Kwadwo , Aboagye Dacosta , Ansong Joana , Ohene Sally-Ann
Published: November 2022

Background

Adequate knowledge about COVID-19 in a population may be relevant in the fight to control its spread among the populace. Thus, the aim of this study was to assess the factors associated with real knowledge of COVID-19 among Ghanaians to promote effective dissemination of appropriate information aimed at containing the spread.

Methods

A cross-sectional online survey and computer assisted telephone interviews (CATI) was conducted among Ghanaians aged 18 years and above across the 260 districts of Ghana. The survey assessed the level of knowledge of COVID-19 and its associated factors and compared differences between perceived and real knowledge. One district health promotion officer per district was trained for the data collection. Participants were recruited via use of phone directories of both organized and non-organized local district groups. Phone calls were made to randomly selected phone contacts to schedule options for participation in the study. We used multivariable logistic regression to investigate the associated factors of COVID-19 knowledge among respondents.

Results

Of the 2,721 participants who completed the survey, the majority (99.3%) were aware of the existence of the COVID-19 outbreak, had good knowledge on infection prevention (87.0%) and rated their knowledge about COVID-19 as good (81.7%). Factors associated with COVID-19 knowledge were: age ≥56 years (aOR = 0.5; CI: 0.3–0.8; p = 0.002), tertiary education (aOR = 1.8; CI: 1.2–2.6; p = 0.003), residing in Greater Accra region (aOR = 2.0; CI: 1.1–3.6; p = 0.019), not infected with the novel coronavirus (aOR = 1.5; Cl: 1.0–2.1; p = 0.045), knowing an infected person (aOR = 3.5; CI = 1.5–7.9; p = 0.003), good practice of effective preventive measures (aOR = 1.2: Cl: 1.1–1.5: 0.008), not misinformed (aOR = 0.7; Cl: 0.5–0.9; 0.015), and perceiving spreading speed of the virus as slow (aOR = 0.7; Cl: 0.5–0.9; 0.007).

Conclusion

The study found good knowledge regarding COVID-19, control measures, and preventive strategies. The Ghana Health Service should continuously provide accurate information to educate the media and citizens to prevent misinformation, which is vital in stopping the spread of the COVID-19 virus.
Selection bias in multidrug-resistant tuberculosis cohort studies assessing sputum culture conversion
Authors: Rodriguez Carly A. , Lodi Sara , Horsburgh C. Robert , Bastard Mathieu , Hewison Cathy , Huerga Helena , Khan Munira , Khan Palwasha Y. , Khan Uzma , Oyewusi Lawrence , Padayachee Shrivani , Mitnick Carole D. , Franke Molly F.
Published: November 2022

Background

Conversion of sputum culture from positive to negative for M. tuberculosis is a key indicator of treatment response. An initial positive culture is a pre-requisite to observe conversion. Consequently, patients with a missing or negative initial culture are excluded from analyses of conversion outcomes. To identify the initial, or “baseline” culture, researchers must define a sample collection interval. An interval extending past treatment initiation can increase sample size but may introduce selection bias because patients without a positive pre-treatment culture must survive and remain in care to have a culture in the post-treatment interval.

Methods

We used simulated data and data from the endTB observational cohort to investigate the potential for bias when extending baseline culture intervals past treatment initiation. We evaluated bias in the proportion with six-month conversion.

Results

In simulation studies, the potential for bias depended on the proportion of patients missing a pre-treatment culture, proportion with conversion, proportion culture positive at treatment initiation, and proportion of patients missing a pre-treatment culture who would have been observed to be culture positive, had they had a culture. In observational data, the maximum potential for bias when reporting the proportion with conversion reached five percentage points in some sites.

Conclusion

Extending the allowable baseline interval past treatment initiation may introduce selection bias. If investigators choose to extend the baseline collection interval past treatment initiation, the proportion missing a pre-treatment culture and the number of deaths and losses to follow up during the post-treatment allowable interval should be clearly enumerated.
Direct RNA sequencing of respiratory syncytial virus infected human cells generates a detailed overview of RSV polycistronic mRNA and transcript abundance
Authors: Donovan-Banfield I’ah , Milligan Rachel , Hall Sophie , Gao Tianyi , Murphy Eleanor , Li Jack , Shawli Ghada T. , Hiscox Julian , Zhuang Xiaodong , McKeating Jane A. , Fearns Rachel , Matthews David A.
Published: November 2022

To characterize species of viral mRNA transcripts generated during respiratory syncytial virus (RSV) infection, human fibroblast-like MRC-5 lung cells were infected with subgroup A RSV for 6, 16 and 24 hours. In addition, we characterised the viral transcriptome in infected Calu-3 lung epithelial cells at 48 hours post infection. Total RNA was harvested and polyadenylated mRNA was enriched and sequenced by direct RNA sequencing using an Oxford nanopore device. This platform yielded over 450,000 direct mRNA transcript reads which were mapped to the viral genome and analysed to determine the relative mRNA levels of viral genes using our in-house ORF-centric pipeline. We examined the frequency of polycistronic readthrough mRNAs were generated and assessed the length of the polyadenylated tails for each group of transcripts. We show a general but non-linear decline in gene transcript abundance across the viral genome, as predicted by the model of RSV gene transcription. However, the decline in transcript abundance is not uniform. The polyadenylate tails generated by the viral polymerase are similar in length to those generated by the host polyadenylation machinery and broadly declined in length for most transcripts as the infection progressed. Finally, we observed that the steady state abundance of transcripts with very short polyadenylate tails less than 20 nucleotides is less for N, SH and G transcripts in both cell lines compared to NS1, NS2, P, M, F and M2 which may reflect differences in mRNA stability and/or translation rates within and between the cell lines.
Synergistic drug combinations designed to fully suppress SARS-CoV-2 in the lung of COVID-19 patients
Authors: De Forni Davide , Poddesu Barbara , Cugia Giulia , Chafouleas James , Lisziewicz Julianna , Lori Franco
Published: November 2022

Despite new antivirals are being approved against SARS-CoV-2 they suffer from significant constraints and are not indicated for hospitalized patients, who are left with few antiviral options. Repurposed drugs have previously shown controversial clinical results and it remains difficult to understand why certain trials delivered positive results and other trials failed. Our manuscript contributes to explaining the puzzle: this might have been caused by a suboptimal drug exposure and, consequently, an incomplete virus suppression, also because the drugs have mostly been used as add-on monotherapies. As with other viruses (e.g., HIV and HCV) identifying synergistic combinations among such drugs could overcome monotherapy-related limitations. In a cell culture model for SARS-CoV-2 infection the following stringent criteria were adopted to assess drug combinations: 1) identify robust, synergistic antiviral activity with no increase in cytotoxicity, 2) identify the lowest drug concentration inhibiting the virus by 100% (LIC100) and 3) understand whether the LIC100 could be reached in the lung at clinically indicated drug doses. Among several combinations tested, remdesivir with either azithromycin or ivermectin synergistically increased the antiviral activity with no increase in cytotoxicity, improving the therapeutic index and lowering the LIC100 of every one of the drugs to levels that are expected to be achievable and maintained in the lung for a therapeutically relevant period of time. These results are consistent with recent clinical observations showing that intensive care unit admission was significantly delayed by the combination of AZI and RDV, but not by RDV alone, and could have immediate implications for the treatment of hospitalized patients with COVID-19 as the proposed “drug cocktails” should have antiviral activity against present and future SARS-CoV-2 variants without significant overlapping toxicity, while minimizing the onset of drug resistance. Our results also provide a validated methodology to help sort out which combination of drugs are most likely to be efficacious in vivo, based on their in vitro activity, potential synergy and PK profiles.
Effects of a yoga-based stress reduction intervention on stress, psychological outcomes and cardiometabolic biomarkers in cancer caregivers: A randomized controlled trial
Authors: Lee Lena J. , Shamburek Robert , Son Hyojin , Wallen Gwenyth R. , Cox Robert , Flynn Sharon , Yang Li , Bevans Margaret , Wehrlen Leslie , Ross Alyson
Published: November 2022

Caregiving stress is a risk factor for cardiometabolic disease. Therefore, integrating cardiometabolic biomarkers into caregiving research provides a more comprehensive assessment of an individual’s health and response to an intervention. The objective of this study was to examine the effects of a yoga-based stress reduction intervention on stress, psychological outcomes, and cardiometabolic biomarkers in cancer caregivers. This prospective randomized controlled trial enrolled family caregivers of adult patients who underwent an allogeneic HSCT at the National Institutes of Health (NIH) Clinical Center. All subjects received usual care education. Participants in the intervention group received an Iyengar yoga intervention self-administered over six weeks using an audio recording file. The primary outcome was perceived stress (measured using the NIH toolbox Perceived Stress). The secondary outcomes were psychological factors (depression and anxiety measured using PROMIS®Depression and Anxiety), and cardiometabolic biomarkers measured by nuclear magnetic resonance spectroscopy. A total of 50 family caregivers (mean [SD] age, 44.9 [15.2] years; 42 [84.0%] women) were randomized, 25 to the intervention group and 25 to the control group. No group differences were noted in stress, depression, and anxiety. Significant interaction effects between group and time were found in large TRL-P (F(1,43) = 10.16,p= 0.003) and LP-IR (F(1,42) = 4.28,p= 0.045). Post-hoc analyses revealed that the levels of large TRL-P (mean difference = 1.68, CI = [0.86, 2.51],p<.001) and LP-IR (mean difference = 5.67, CI = [1.15, 10.18],p =0.015) significantly increased over time in the control group but while remained stable in the intervention group (mean difference = -0.15, CI = [-0.96, 0.66],p= 0.718; mean difference = -0.81, CI = [-5.22, 3.61],p= 0.714, respectively). Even when perceptions of psychological distress remain unchanged, incorporating gentle yoga poses and breathing exercises may reduce the risk of cardiometabolic disease in caregivers by inhibiting the development of insulin resistance. Standard lipids of cardiometabolic risk do not appear to be robust enough to detect short-term early changes of cardiometabolic risk in caregivers.

Trial registration: ClinicalTrials.gov Identifier:NCT02257853.
Association of non-chronic low back pain with physical function, endurance, fatigability, and quality of life in middle- and older-aged adults: Findings from Baltimore Longitudinal Study of Aging
Authors: Gonçalves Tatiana Rehder , Cunha Diana Barbosa , Mediano Mauro F. F. , Wanigatunga Amal A. , Simonsick Eleanor M. , Schrack Jennifer A.
Published: November 2022

Low back pain (LBP) is an important condition associated with high healthcare burden. However, the relationship of this condition with physical function (PF) and health-related quality of life (HRQoL) remains unclear. This is a cross-sectional study that aims to investigate the association between presence and intensity of non-chronic LBP with PF and HRQoL in middle-and older-aged adults. Participants answered questions about presence and intensity of LBP in the previous year, self-reported their PF and HRQoL (SF-12), and underwent objective measures of PF ([ExSPPB] including usual gait speed, narrow walk, chair stands, and standing balance), endurance performance ([EP] long-distance corridor walk) and fatigability. Generalized linear models and logistic regression models were performed. A total of 1500 participants (52.5% women, 70.3% white) aged 69.0 (SD 13.1) years were included. Of those, 642 (42.8%) reported LBP and the mean pain intensity was 4.1 (SD 2.2). After adjustments for potential confounders, presence of LBP was associated with lower self-reported PF (OR 1.73, 95% CI 1.27 to 2.37), lower physical component of HRQoL (β -0.03, 95% CI -0.04 to -0.02) and poorer chair stand performance (β -0.05, 95% CI -0.09 to -0.008). Higher intensity of LBP was associated with lower physical component of HRQoL (β -0.01, 95% CI -0.02 to -0.007), poorer ExSPPB performance (β -0.01, 95% CI -0.02 to -0.004), slower usual gait speed (β -0.01, 95% CI -0.02 to -0.004), lower total standing balance time (β -0.01, 95% CI -0.02 to -0.001) and higher fatigability (OR 1.13, 95% CI 1.01 to 1.25). The presence of non-chronic LBP was more consistently associated with lower self-reported PF, while higher intensity non-chronic LBP was associated with poorer objectively measured PF and fatigability. Collectively, this evidence suggests that although presence of pain may affect perception of function, greater pain intensity appears more strongly associated with unfavorable functional performance in mid-to-late life.
Circulatory C-type natriuretic peptide reduces mucopolysaccharidosis-associated craniofacial hypoplasia in vivo
Authors: Kashiwagi Marina , Nakao Kazumasa , Yamanaka Shigeki , Yamauchi Ichiro , Yamashita Takafumi , Fujii Toshihito , Ueda Yohei , Kawai Mariko Yamamoto , Watanabe Takuma , Fukuhara Shizuko , Bessho Kazuhisa
Published: November 2022

Skeletal alterations in the head and neck region, such as midfacial hypoplasia, foramen magnum stenosis and spinal canal stenosis, are commonly observed in patients with mucopolysaccharidosis (MPS). However, enzyme replacement therapy (ERT), one of the major treatment approaches for MPS, shows limited efficacy for skeletal conditions. In this study, we analysed the craniofacial morphology of mice with MPS type VII, and investigated the underlying mechanisms promoting jaw deformities in these animals. Furthermore, we investigated the effects of C-type natriuretic peptide (CNP), a potent endochondral ossification promoter, on growth impairment of the craniofacial region in MPS VII mice when administered alone or in combination with ERT. MPS VII mice exhibited midfacial hypoplasia caused by impaired endochondral ossification, and histological analysis revealed increased number of swelling cells in the resting zone of the spheno-occipital synchondrosis (SOS), an important growth centre for craniomaxillofacial skeletogenesis. We crossed MPS VII mice with transgenic mice in which CNP was expressed in the liver under the control of the human serum amyloid-P component promoter, resulting in elevated levels of circulatory CNP. The maxillofacial morphological abnormalities associated with MPS VII were ameliorated by CNP expression, and further prevented by a combination of CNP and ERT. Histological analysis showed that ERT decreased the swelling cell number, and CNP treatment increased the width of the proliferative and hypertrophic zones of the SOS. Furthermore, the foramen magnum and spinal stenoses observed in MPS VII mice were significantly alleviated by CNP and ERT combination. These results demonstrate the therapeutic potential of CNP, which can be used to enhance ERT outcome for MPS VII-associated head and neck abnormalities.