bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultralow sidelobe midinfrared optical phased array based on a broadband metasurface
Authors: Wang Yue , Wang Yu , Yang Guohui , Li Qingyan , Zhang Bin , Wang Chunhui
Published: September 2021

In this paper, we propose an all-solid-state and ultralow sidelobe optical phased array (OPA) through designing a broadband angle-insensitive reflective metasurface in the midinfrared. The simulation results show that the metasurface can realize the wide-frequency metareflection characteristics in the range of4.3∼5.0µm. Notably, the metasurface array can almost generate a continuous sweep between 0° and 342°, while the variation of reflectivity amplitude is only 10.2%, by changing the corresponding structural parameters. Then, we design and simulate an OPA based on these excellent characteristics of the broadband metasurface. By simply changing the periodicity of the OPA structure, the continuous deflection angles can be achieved within 29.41°, which can increase to 44.06° by changing the angle of the incident beam. A key feature of our design is that the sidelobe energy is less than 3.10% of the main lobe energy.
Multi-task learning approach for volumetric segmentation and reconstruction in 3D OCT images
Authors: Cahyo Dheo A. Y. , Yow Ai Ping , Saw Seang-Mei , Ang Marcus , Girard Michael , Schmetterer Leopold , Wong Damon
Published: September 2021

The choroid is the vascular layer of the eye that supplies photoreceptors with oxygen. Changes in the choroid are associated with many pathologies including myopia where the choroid progressively thins due to axial elongation. To quantize these changes, there is a need to automatically and accurately segment the choroidal layer from optical coherence tomography (OCT) images. In this paper, we propose a multi-task learning approach to segment the choroid from three-dimensional OCT images. Our proposed architecture aggregates the spatial context from adjacent cross-sectional slices to reconstruct the central slice. Spatial context learned by this reconstruction mechanism is then fused with a U-Net based architecture for segmentation. The proposed approach was evaluated on volumetric OCT scans of 166 myopic eyes acquired with a commercial OCT system, and achieved a cross-validation Intersection over Union (IoU) score of 94.69% which significantly outperformed (p<0.001) the other state-of-the-art methods on the same data set. Choroidal thickness maps generated by our approach also achieved a better structural similarity index (SSIM) of 72.11% with respect to the groundtruth. In particular, our approach performs well for highly challenging eyes with thinner choroids. Compared to other methods, our proposed approach also requires lesser processing time and has lower computational requirements. The results suggest that our proposed approach could potentially be used as a fast and reliable method for automated choroidal segmentation.
High linear polarization, narrow linewidth hybrid semiconductor laser with an external birefringence waveguide Bragg grating
Authors: Luo Xi-chen , Chen Chao , Ning Yong-qiang , Zhang Xing , Qiu Cheng , Chen Jia-qi , Yin Xiao-jie , Qin Li , Wang Li-jun
Published: September 2021

We demonstrate a high linear polarization, narrow linewidth hybrid laser composed of a semiconductor gain chip and a high birefringence waveguide Bragg grating (WBG). The laser operates in the C-band, and a maximum output power of 8.07 mW is obtained in the fiber waveguide. With careful temperature tuning, the hybrid laser can operate in a single longitudinal mode state from above the threshold current to 410 mA. The side mode suppression ratio (SMSR) reaches a value of 50.2 dB, and the polarization extinction ratio exceeds 39.6 dB. We numerically analyze the linewidth suppression for the Bragg grating based on adiabatic chirp theory. The hybrid laser shows a narrow linewidth of 4.15 kHz and a low relative intensity noise (RIN) of <-155 dBc/Hz, providing a high-performance light source for coherent light communication.
Temperature dependent Raman spectra of ammonia ranging from 3150 cm−1 to 3810 cm−1 for combustion applications
Authors: Yang Chaobo , Ezendeeva Diana , Yu Tao , Magnotti Gaetano
Published: September 2021

Applying in combustion research, Raman scattering technique can provide high accuracy and high precision measurements of temperature and major species concentrations. However detailed knowledge of the temperature dependent Raman spectra of the probed species is a precondition to realise the potential of high precision and accuracy of the technique. As a carbon free novel fuel, the knowledge of high temperature Raman spectra of ammonia is rarely reported. We measured the Raman spectra of ammonia ranging from 299 K to 760 K. The high resolution Raman spectra are excited with a continuous wave 532 nm laser and detected with an low aberration Schmidt-Czerny-Turner spectrometer. The temperature of probe volume was determined by the fitting of N2 Raman spectra. The Raman spectra of ammonia under different temperatures were quantitatively normalized to the same number density to research the temperature behavior of spectra. Within the Raman shift region from 3150 cm−1 to 3810 cm−1, the Raman intensity and the polarization anisotropy of vibrational modes ν1, ν3, and 2ν4 were reported. The relative intensity between ν1, ν3, and 2ν4 modes were also analyzed under different temperatures.
Formation mechanism of bubbles in the crack healing process of fused silica using a CO2 laser
Authors: Yang Zican , Cheng Jian , Chen Mingjun , Zhao Linjie , Li Yaguo , Xu Qiao , Liu Zhichao , Geng Feng , Tan Chao , Xu Hongguang
Published: September 2021

The machining-induced cracks and other defects on the surface of fused silica would incur damage when irradiated by intense lasers, which greatly shortens the service life of the fused silica optical components. The high absorption coefficient of fused silica for far-infrared lasers makes it possible to use low-energy CO2 lasers to melt and heal micro defects on the surface, and hence improve its damage threshold under the service conditions of extremely intense laser. However, the air in the cracks may evolve into bubbles during the laser healing process, but the law of crack morphology evolution and the bubble formation mechanism have not been clearly revealed. In this work, a simulation model of the healing process of fused silica surface cracks under the effect of low-energy CO2 laser is established. Three bubble formation mechanisms (i.e., the uneven fluidity caused by temperature gradient, the collapse effect caused by inclined cracks, and the internal cracks) are identified based on the simulation results of cracks with various original morphologies and characteristic structural parameters. The simulated fused silica morphology is consistent with the results of the laser healing experiment. This work can provide theoretical guidance for the optimization of optical manufacturing parameters of fused silica, as well as the CO2 laser healing and polishing strategies.
Liquid-cladded optical phased array for a single-wavelength beam steering
Authors: Li Binghui , Sun Caiming , Wang Hongjie , Chen Zhenmin , Nie Xiaomin , Deng Shupeng , Yang Lesi , Zhang Aidong
Published: September 2021

We report a simple concept to implement a single-wavelength beam steering based on a liquid-cladded one-dimensional (1D) optical phased array (OPA). The beam steering was realized by modifying the waveguide mode effective index through replacing the liquid upper claddings. A prototype of a 32-channel liquid-cladded OPA was fabricated and characterized. Owing to the high refractive index range of liquids (

>

0.625

), a maximum steering angle of

>

10

∘

was achieved with the liquid range from 1.0 to 1.63 at a wavelength of 940 nm. Moreover, the liquid-cladded OPA reveals a quasi-continuous beam steering range of

>

29

∘

by combining the liquid cladding tuning and discrete wavelength tuning of

λ
=

785

n
m

, 852 nm, and 940 nm. Further integration with optofluidic systems offers the OPA potential for low power consumption and all-fluidic beam steering operating at a single wavelength.
Resolution improvement in real-time and video mosaicing for fiber bundle imaging
Authors: Huang Yang , Zhou Wei , Xu Baoteng , Liu Jialin , Xiong Daxi , Yang Xibin
Published: September 2021

A fiber bundle allows easy access to a wide range of human tissue. It has smaller diameters, which limits its effective field of view (FOV), and consists of a large number of cores surrounded by a cladding layer, which reduces its spatial resolution. In this paper, we develop an algorithm that processes successively captured raw fiber bundle images in an online fashion. Our algorithm tackles the tasks of super-resolution (SR) and video mosaicing jointly. The natural movement of the fiber tip in successive frames produces offsets that are random in the pixel domain to apply multi-frame SR imaging. Meanwhile, the associated FOV can be extended by mosaicing reconstructed SR images with obtained shifted information. Our approach has low computational complexity that allows for processing in real-time. The performance of resolution improvement in real-time and video mosaicing is demonstrated on the resolution target and biological samples.
Crowdsourced identification of multi-target kinase inhibitors for RET- and TAU- based disease: The Multi-Targeting Drug DREAM Challenge
Authors: Xiong Zhaoping , Jeon Minji , Allaway Robert J. , Kang Jaewoo , Park Donghyeon , Lee Jinhyuk , Jeon Hwisang , Ko Miyoung , Jiang Hualiang , Zheng Mingyue , Tan Aik Choon , Guo Xindi ,   The Multi-Targeting Drug DREAM Challenge Community, Dang Kristen K. , Tropsha Alex , Hecht Chana , Das Tirtha K. , Carlson Heather A. , Abagyan Ruben , Guinney Justin , Schlessinger Avner , Cagan Ross
Published: September 2021

A continuing challenge in modern medicine is the identification of safer and more efficacious drugs. Precision therapeutics, which have one molecular target, have been long promised to be safer and more effective than traditional therapies. This approach has proven to be challenging for multiple reasons including lack of efficacy, rapidly acquired drug resistance, and narrow patient eligibility criteria. An alternative approach is the development of drugs that address the overall disease network by targeting multiple biological targets (‘polypharmacology’). Rational development of these molecules will require improved methods for predicting single chemical structures that target multiple drug targets. To address this need, we developed the Multi-Targeting Drug DREAM Challenge, in which we challenged participants to predict single chemical entities that target pro-targets but avoid anti-targets for two unrelated diseases: RET-based tumors and a common form of inherited Tauopathy. Here, we report the results of this DREAM Challenge and the development of two neural network-based machine learning approaches that were applied to the challenge of rational polypharmacology. Together, these platforms provide a potentially useful first step towards developing lead therapeutic compounds that address disease complexity through rational polypharmacology.
Impact of decreasing the proportion of higher energy foods and reducing portion sizes on food purchased in worksite cafeterias: A stepped-wedge randomised controlled trial
Authors: Reynolds James P. , Ventsel Minna , Kosīte Daina , Rigby Dames Brier , Brocklebank Laura , Masterton Sarah , Pechey Emily , Pilling Mark , Pechey Rachel , Hollands Gareth J. , Marteau Theresa M.
Published: September 2021

Background

Overconsumption of energy from food is a major contributor to the high rates of overweight and obesity in many populations. There is growing evidence that interventions that target the food environment may be effective at reducing energy intake. The current study aimed to estimate the effect of decreasing the proportion of higher energy (kcal) foods, with and without reducing portion size, on energy purchased in worksite cafeterias.

Methods and findings

This stepped-wedge randomised controlled trial (RCT) evaluated 2 interventions: (i) availability: replacing higher energy products with lower energy products; and (ii) size: reducing the portion size of higher energy products. A total of 19 cafeterias were randomised to the order in which they introduced the 2 interventions. Availability was implemented first and maintained. Size was added to the availability intervention. Intervention categories included main meals, sides, cold drinks, snacks, and desserts. The study setting was worksite cafeterias located in distribution centres for a major United Kingdom supermarket and lasted for 25 weeks (May to November 2019). These cafeterias were used by 20,327 employees, mainly (96%) in manual occupations. The primary outcome was total energy (kcal) purchased from intervention categories per day. The secondary outcomes were energy (kcal) purchased from nonintervention categories per day, total energy purchased per day, and revenue. Regression models showed an overall reduction in energy purchased from intervention categories of −4.8% (95% CI −7.0% to −2.7%), p < 0.001 during the availability intervention period and a reduction of −11.5% (95% CI −13.7% to −9.3%), p < 0.001 during the availability plus size intervention period, relative to the baseline. There was a reduction in energy purchased of −6.6% (95% CI −7.9% to −5.4%), p < 0.001 during the availability plus size period, relative to availability alone. Study limitations include using energy purchased as the primary outcome (and not energy consumed) and the availability only of transaction-level sales data per site (and not individual-level data).

Conclusions

Decreasing the proportion of higher energy foods in cafeterias reduced the energy purchased. Decreasing portion sizes reduced this further. These interventions, particularly in combination, may be effective as part of broader strategies to reduce overconsumption of energy from food in out-of-home settings.

Trial registration

ISRCTN registry ISRCTN87225572.
Socioeconomic inequalities in prevalence and development of multimorbidity across adulthood: A longitudinal analysis of the MRC 1946 National Survey of Health and Development in the UK
Authors: Khanolkar Amal R. , Chaturvedi Nishi , Kuan Valerie , Davis Daniel , Hughes Alun , Richards Marcus , Bann David , Patalay Praveetha
Published: September 2021

Background

We aimed to estimate multimorbidity trajectories and quantify socioeconomic inequalities based on childhood and adulthood socioeconomic position (SEP) in the risks and rates of multimorbidity accumulation across adulthood.

Methods and findings

Participants from the UK 1946 National Survey of Health and Development (NSHD) birth cohort study who attended the age 36 years assessment in 1982 and any one of the follow-up assessments at ages 43, 53, 63, and 69 years (N = 3,723, 51% males). Information on 18 health conditions was based on a combination of self-report, biomarkers, health records, and prescribed medications. We estimated multimorbidity trajectories and delineated socioeconomic inequalities (based on childhood and adulthood social class and highest education) in multimorbidity at each age and in longitudinal trajectories.

Multimorbidity increased with age (0.7 conditions at 36 years to 3.7 at 69 years). Multimorbidity accumulation was nonlinear, accelerating with age at the rate of 0.08 conditions/year (95% CI 0.07 to 0.09, p < 0.001) at 36 to 43 years to 0.19 conditions/year (95% CI 0.18 to 0.20, p < 0.001) at 63 to 69 years. At all ages, the most socioeconomically disadvantaged had 1.2 to 1.4 times greater number of conditions on average compared to the most advantaged. The most disadvantaged by each socioeconomic indicator experienced an additional 0.39 conditions (childhood social class), 0.83 (adult social class), and 1.08 conditions (adult education) at age 69 years, independent of all other socioeconomic indicators. Adverse adulthood SEP was associated with more rapid accumulation of multimorbidity, resulting in 0.49 excess conditions in partly/unskilled compared to professional/intermediate individuals between 63 and 69 years. Disadvantaged childhood social class, independently of adulthood SEP, was associated with accelerated multimorbidity trajectories from age 53 years onwards.

Study limitations include that the NSHD cohort is composed of individuals of white European heritage only, and findings may not be generalizable to the non-white British population of the same generation and did not account for other important dimensions of SEP such as income and wealth.

Conclusions

In this study, we found that socioeconomically disadvantaged individuals have earlier onset and more rapid accumulation of multimorbidity resulting in widening inequalities into old age, with independent contributions from both childhood and adulthood SEP.
Grasp aperture corrections in reach-to-grasp movements do not reliably alter size perception
Authors: van Polanen Vonne
Published: September 2021

When grasping an object, the opening between the fingertips (grip aperture) scales with the size of the object. If an object changes in size, the grip aperture has to be corrected. In this study, it was investigated whether such corrections would influence the perceived size of objects. The grasping plan was manipulated with a preview of the object, after which participants initiated their reaching movement without vision. In a minority of the grasps, the object changed in size after the preview and participants had to adjust their grasping movement. Visual feedback was manipulated in two experiments. In experiment 1, vision was restored during reach and both visual and haptic information was available to correct the grasp and lift the object. In experiment 2, no visual information was provided during the movement and grasps could only be corrected using haptic information. Participants made reach-to-grasp movements towards two objects and compared these in size. Results showed that participants adjusted their grasp to a change in object size from preview to grasped object in both experiments. However, a change in object size did not bias the perception of object size or alter discrimination performance. In experiment 2, a small perceptual bias was found when objects changed from large to small. However, this bias was much smaller than the difference that could be discriminated and could not be considered meaningful. Therefore, it can be concluded that the planning and execution of reach-to-grasp movements do not reliably affect the perception of object size.
COVID-19-associated school closures and related efforts to sustain education and subsidized meal programs, United States, February 18–June 30, 2020
Authors: Zviedrite Nicole , Hodis Jeffrey D. , Jahan Ferdous , Gao Hongjiang , Uzicanin Amra
Published: September 2021

Pre-emptive school closures are frontline community mitigation measures recommended by the US Centers for Disease Control and Prevention (CDC) for implementation during severe pandemics. This study describes the spatiotemporal patterns of publicly announced school closures implemented in response to the coronavirus disease 2019 (COVID-19) pandemic and assesses how public K-12 districts adjusted their methods of education delivery and provision of subsidized meals. During February 18–June 30, 2020, we used daily systematic media searches to identify publicly announced COVID-19–related school closures lasting ≥1 day in the United States (US). We also collected statewide school closure policies from state government websites. Data on distance learning and subsidized meal programs were collected from a stratified sample of 600 school districts. The first COVID-19–associated school closure occurred on February 27, 2020 in Washington state. By March 30, 2020, all but one US public school districts were closed, representing the first-ever nearly synchronous nationwide closure of public K-12 schools in the US. Approximately 100,000 public schools were closed for ≥8 weeks because of COVID-19, affecting >50 million K-12 students. Of 600 districts sampled, the vast majority offered distance learning (91.0%) and continued provision of subsidized meal programs (78.8%) during the closures. Despite the sudden and prolonged nature of COVID-19–associated school closures, schools demonstrated flexibility by implementing distance learning and alternate methods to continue subsidized meal programs.
A murine model of the human CREBRFR457Q obesity-risk variant does not influence energy or glucose homeostasis in response to nutritional stress
Authors: Kanshana Jitendra S. , Mattila Polly E. , Ewing Michael C. , Wood Ashlee N. , Schoiswohl Gabriele , Meyer Anna C. , Kowalski Aneta , Rosenthal Samantha L. , Gingras Sebastien , Kaufman Brett A. , Lu Ray , Weeks Daniel E. , McGarvey Stephen T. , Minster Ryan L. , Hawley Nicola L. , Kershaw Erin E.
Published: September 2021

Obesity and diabetes have strong heritable components, yet the genetic contributions to these diseases remain largely unexplained. In humans, a missense variant in Creb3 regulatory factor (CREBRF) [rs373863828 (p.Arg457Gln); CREBRFR457Q] is strongly associated with increased odds of obesity but decreased odds of diabetes. Although virtually nothing is known about CREBRF’s mechanism of action, emerging evidence implicates it in the adaptive transcriptional response to nutritional stress downstream of TORC1. The objectives of this study were to generate a murine model with knockin of the orthologous variant in mice (CREBRFR458Q) and to test the hypothesis that this CREBRF variant promotes obesity and protects against diabetes by regulating energy and glucose homeostasis downstream of TORC1. To test this hypothesis, we performed extensive phenotypic analysis of CREBRFR458Qknockin mice at baseline and in response to acute (fasting/refeeding), chronic (low- and high-fat diet feeding), and extreme (prolonged fasting) nutritional stress as well as with pharmacological TORC1 inhibition, and aging to 52 weeks. The results demonstrate that the murine CREBRFR458Qmodel of the human CREBRFR457Qvariant does not influence energy/glucose homeostasis in response to these interventions, with the exception of possible greater loss of fat relative to lean mass with age. Alternative preclinical models and/or studies in humans will be required to decipher the mechanisms linking this variant to human health and disease.
Lack of effect on in-hospital mortality of drugs used during COVID-19 pandemic: Findings of the retrospective multicenter COVOCA study
Authors: Pafundi Pia Clara , Galiero Raffaele , Simeon Vittorio , Rinaldi Luca , Perrella Alessandro , Vetrano Erica , Caturano Alfredo , Alfano Maria , Beccia Domenico , Nevola Riccardo , Marfella Raffaele , Sardu Celestino , Coppola Carmine , Scarano Ferdinando , Maggi Paolo , De Lucia Sposito Pellegrino , Vocciante Laura , Rescigno Carolina , Sbreglia Costanza , Fraganza Fiorentino , Parrella Roberto , Romano Annamaria , Calabria Giosuele , Polverino Benedetto , Pagano Antonio , Bologna Carolina , Amitrano Maria , Esposito Vincenzo , Coppola Nicola , Maturo Nicola , Adinolfi Luigi Elio , Chiodini Paolo , Sasso Ferdinando Carlo ,   on behalf of COVOCA Study Group
Published: September 2021

Introduction

During COVID-19 pandemic, the use of several drugs has represented the worldwide clinical practice. However, though the current increase of knowledge about the disease, there is still no effective treatment for the usage of drugs. Thus, we retrospectively assessed use and effects of therapeutic regimens in hospitalized patients on in-hospital mortality.

Methods

COVOCA is a retrospective observational cohort study on 18 COVID centres throughout Campania Region Hospitals. We included adult patients with confirmed SARS-CoV-2 infection, discharged/dead between March/June 2020.

Results

618 patients were included, with an overall in-hospital cumulative mortality incidence of 23.1%. Most prescribed early treatments were antivirals (72%), antibiotics (65%) and hydroxychloroquine/anticoagulants (≈50%). Tocilizumab, indeed, was largely prescribed late during hospitalization. Multivariable models, with a cut-off at day 2 for early COVID-19 therapy administration, did not disclose any significant association of a single drug administration on the clinical outcome.

Discussion

COVOCA represents the first multicenter database in Campania region. None drug class used during the pandemic significantly modified the outcome, regardless of therapy beginning, both overall and net of those already in non-invasive ventilation (NIV)/ orotracheal intubation (OTI) at hospitalization. Our cumulative incidence of mortality seems lower than other described during the same period, particularly in Northern Italy.
Improving fake news classification using dependency grammar
Authors: Nagy Kitti , Kapusta Jozef
Published: September 2021

Fake news is a complex problem that leads to different approaches used to identify them. In our paper, we focus on identifying fake news using its content. The used dataset containing fake and real news was pre-processed using syntactic analysis. Dependency grammar methods were used for the sentences of the dataset and based on them the importance of each word within the sentence was determined. This information about the importance of words in sentences was utilized to create the input vectors for classifications. The paper aims to find out whether it is possible to use the dependency grammar to improve the classification of fake news. We compared these methods with the TfIdf method. The results show that it is possible to use the dependency grammar information with acceptable accuracy for the classification of fake news. An important finding is that the dependency grammar can improve existing techniques. We have improved the traditional TfIdf technique in our experiment.
Off-chip prefetching based on Hidden Markov Model for non-volatile memory architectures
Authors: Lamela Adrián , Ossorio Óscar G. , Vinuesa Guillermo , Sahelices Benjamín
Published: September 2021

Non-volatile memory technology is now available in commodity hardware. This technology can be used as a backup memory for an external dram cache memory without needing to modify the software. However, the higher read and write latencies of non-volatile memory may exacerbate the memory wall problem. In this work we present a novel off-chip prefetch technique based on a Hidden Markov Model that specifically deals with the latency problem caused by complexity of off-chip memory access patterns. Firstly, we present a thorough analysis of off-chip memory access patterns to identify its complexity in multicore processors. Based on this study, we propose a prefetching module located in the llc which uses two small tables, and where the computational complexity of which is linear with the number of computing threads. Our Markov-based technique is able to keep track and make clustering of several simultaneous groups of memory accesses coming from multiple simultaneous threads in a multicore processor. It can quickly identify complex address groups and trigger prefetch with very high accuracy. Our simulations show an improvement of up to 76% in the hit ratio of an off-chip dram cache for multicore architecture over the conventional prefetch technique (g/dc). Also, the overhead of prefetch requests (failed prefetches) is reduced by 48% in single core simulations and by 83% in multicore simulations.
The gap between desired and expected fertility among women in Iran: A case study of Tehran city
Authors: Hosseini Maryam , Saikia Udoy , Dasvarma Gouranga
Published: September 2021

The 2016 Iranian Census reveals that 14 of the country’s 31 provinces have sub-replacement fertility. The province of Tehran, where a woman on average gives birth to 1.5 children during her reproductive period, has the lowest fertility in Iran. However, the ‘two-child’ norm prevails in the country and even a woman of young reproductive age still values having at least two children on average. In other words, there exists a gap between a woman’s actual and desired fertility. This paper examines the demographic and socio-economic factors influencing the gap between actual and desired fertility in Tehran city based on a sample survey of 400 married women aged 15–49 years, conducted in 2015. The findings of the study reveal that the women of Tehran would be able to meet their fertility desires of two or more children if they were able to achieve their intended number of children they stated in the survey. However, should these women face any socio-economic constraint, they would be very likely to restrain their fertility desires and have fewer additional children than they initially intended, and thus continue with the sub-replacement fertility as being observed in Iran today.
Using a stair horizontal-vertical illusion to increase foot clearance over an inconsistently taller stair-riser
Authors: Skervin Timmion K. , Thomas Neil M. , Schofield Andrew J. , Hollands Mark A. , Maganaris Constantinos N. , O’Brien Thomas D. , Baltzopoulos Vasilios , Foster Richard J.
Published: September 2021

Introduction

Stair falls can be caused by inconsistent stair dimensions. During ascent, inconsistently taller stair risers lead to reduced foot clearances as the inconsistency goes unnoticed. A stair horizontal-vertical illusion increases perceived riser heights and foot clearance and could offset reduced foot clearances over inconsistently taller risers, though this might impact other stair safety measures.

Method

Twelve participants (age: 22 (3) years) ascended a seven-step staircase under three conditions: i) all steps consistent in riser height (consistent), ii) a 1cm increase in step 5 riser height (inconsistent) and iii) a 1cm increase in step 5 riser height, superimposed with a stair horizontal-vertical illusion (illusion). Vertical foot clearance, foot overhang, and margins of stability were assessed over step 4, 5 and 6. Perceived riser height due to the illusion was determined through a computer perception test. A One-Way Repeated Measures ANOVA compared biomechanical variables between conditions. A One Sample t test compared perceived riser height to the true height.

Results

Over the inconsistent step 5, foot clearance reduced by 0.8cm compared to consistent. Illusion increased foot clearance by 1.1cm and decreased foot overhang by 4% compared to inconsistent. On step 4 the illusion led to more anterior instability compared to inconsistent. Illusion and inconsistent led to more mediolateral stability compared to consistent. The illusion increased perceived riser height by 12%.

Discussion

Foot clearance reductions over inconsistently taller risers can be offset by a stair horizontal-vertical illusion. Additional benefits included a safer foot overhang and unaffected stability over the inconsistent riser. Changes to step 4 stability might have resulted from leaning forward to look at the step 5 illusion. The stair horizontal-vertical illusion could be a practical solution for inconsistently taller stair risers, where a rebuild is usually the only solution.
Problematic internet use profiles and psychosocial risk among adolescents
Authors: Pontes Halley M. , Macur Mirna
Published: September 2021

Objective

Although Problematic Internet Use (PIU) is an emerging area of study in psychology, little is known about the unique features of specific subgroups of internet users and their psychosocial vulnerabilities within robust and nationwide populations.

Methods

The aim of this study was to identify distinct latent groups of internet users based on their PIU risk and to compare their psychosocial outcomes. To achieve this, a nationally representative sample of adolescents of the same grade (N= 1,066, Meanage= 13.46 years, range = 12–16) was recruited from several schools in Slovenia through stratified random sampling.

Results

A Latent Profile Analysis (LPA) revealed a two-class solution, with Class 1 (n= 853, 80%) featuring ‘low PIU risk’ participants and Class 2 (n= 213, 20%) including ‘high PIU risk’ participants. Behaviorally, the main feature of Class 1 denoted ‘time management difficulties’ while Class 2 was best characterized by ‘mood and time management issues’. Further frequentist and Bayesian analyses indicated that Class 2 presented greater psychosocial risk compared to Class 1 due to significantly higher levels of PIU (generalized and across specific PIU subfactors) coupled with lower levels of subjective well-being and self-control.

Conclusions

Contrary to what was initially envisaged, the two classes did not differ in terms of perceived quality in parent-child relationship. This study shows that PIU patterns and symptom-severity may be developmentally specific, further highlighting the need for clinically age-adjusted PIU screening practices within epidemiological and healthcare settings.
Development of in-house, indirect ELISAs for the detection of SARS-CoV-2 spike protein-associated serology in COVID-19 patients in Panama
Authors: de la Guardia Carolina , Rangel Giselle , Villarreal Alcibiades , Goodridge Amador , Fernández Patricia L. , Lleonart Ricardo
Published: September 2021

COVID-19 is the name of the acute respiratory disease caused by the new coronavirus SARS-CoV-2, a close relative of those that caused the severe outbreaks of SARS and MERS several years ago. Since first appearance on December of 2019, the COVID-19 pandemic has cause extremely high levels of mortality, morbidity, global economic breakdown, and the consequent human suffering. The main diagnostic test for the confirmation of symptomatic individuals is the detection of viral RNA by reverse transcriptase–quantitative real time PCR (RT-PCR). Additionally, serology techniques, such as ELISA are useful to measure the antibodies produced in humans after contact with the virus, as well as the direct presence of viral antigens. In this study we aim to assemble and evaluate four ELISA assays to measure the presence of IgG or IgM specific for the viral Spike protein in COVID-19 patients, using either the full recombinant SARS-CoV-2 Spike protein or the fragment corresponding to the receptor binding domain. As a control, we analyzed a group of pre-pandemic serum samples obtained before 2017. Strong reactivity was observed against both antigens. A few pre-pandemic samples displayed high OD values, suggesting the possibility of some cross reactivity. All four assays show very good repeatability, both intra- and inter-assay. Receiver operating characteristic analysis allowed the definition of cutoffs and evaluation of performance for each ELISA by estimation of the area under the curve. This performance parameter was high for all tests (AUC range: 0.98–0.99). Multiple comparisons between tests revealed no significant difference between each other (P values: 0.24–0.95). Our results show that both antigens are effective to detect both specific IgG and IgM antibodies, with high sensitivity (range 0.92–0.99), specificity (range 0.93–0.97) and congruence with the RT-PCR test (Cohen´s Kappa range 0.87–0.93). These assays will allow health authorities to have a new tool to estimate seroprevalence, in order to manage and improve the severe sanitary situation caused by this virus.
A national survey of antibacterial consumption in Sri Lanka
Authors: Sri Ranganathan Shalini , Wanigatunge Chandanie , Senadheera G. P. S. G. , Beneragama B. V. S. H.
Published: September 2021

Introduction

Optimizing the use of antibacterial medicines is an accepted strategy to combat the antibacterial resistance. Availability of reliable antibacterial consumption (ABC) data is a prerequisite to implement this strategy.

Objectives

To quantify and describe the national ABC in Sri Lanka and to examine any differences in the consumption between public and private sector.

Methods

The methodology for this survey was adapted from World Health Organization (WHO) methodology for a global programme on surveillance of antimicrobial consumption. Aggregate data on national consumption of systemic antibacterials (J01- Anatomical Therapeutic Chemical Classification (ATC) for 2017 were retrospectively extracted from all available data sources and classified using ATC classification. Quantity of consumption was converted to Defined Daily Doses (DDDs). Data are presented as total consumption and comparison between the public and private sector. Selected key quality indicators of ABC were compared between these two sectors.

Findings

From the available data sources, the total ABC in 2017 was 343.46 million DDDs. Private sector consumption accounted for 246.76 million DDDs compared to 97.96 million DDDs distributed to entire public sector by the Ministry of Health. Beta-lactam-penicillins antibacterial group accounted for 58.79% in public sector compared to 27.48% in private sector while macrolides, quinolones and other beta-lactam antibacterials accounted for 60.51% in the private compared to 28.41% in public sector. Consumption of Reserve group antibacterials was negligible, and limited to private sector. Watch category antibacterials accounted for 46%, 24% and 54% of the total, public and private sector consumption, respectively.

Conclusions

A disproportionately higher use of broad spectrum and Watch category antibacterials was observed in the private sector which needs further study. This national consumption survey highlights the need and provides the opening for establishment of ABC surveillance in Sri Lanka.
Quantifying transmission dynamics of acute hepatitis C virus infections in a heterogeneous population using sequence data
Authors: Danesh Gonché , Virlogeux Victor , Ramière Christophe , Charre Caroline , Cotte Laurent , Alizon Samuel
Published: September 2021

Opioid substitution and syringes exchange programs have drastically reduced hepatitis C virus (HCV) spread in France but HCV sexual transmission in men having sex with men (MSM) has recently arisen as a significant public health concern. The fact that the virus is transmitting in a heterogeneous population, with different transmission routes, makes prevalence and incidence rates poorly informative. However, additional insights can be gained by analyzing virus phylogenies inferred from dated genetic sequence data. By combining a phylodynamics approach based on Approximate Bayesian Computation (ABC) and an original transmission model, we estimate key epidemiological parameters of an ongoing HCV epidemic among MSMs in Lyon (France). We show that this new epidemic is largely independent of the previously observed non-MSM HCV epidemics and that its doubling time is ten times lower (0.44 years versus 4.37 years). These results have practical implications for HCV control and illustrate the additional information provided by virus genomics in public health.
FluWatchers: Evaluation of a crowdsourced influenza-like illness surveillance application for Canadian influenza seasons 2015–2016 to 2018–2019
Authors: Lee Liza , Desroches Mireille , Mukhi Shamir , Bancej Christina
Published: September 2021

Background: Sentinel influenza-like illness (ILI) surveillance is an essential component of a comprehensive influenza surveillance program. Community-based ILI surveillance systems that rely solely on sentinel healthcare practices omit important segments of the population, including those who do not seek medical care. Participatory surveillance, which relies on community participation in surveillance, may address some limitations of traditional ILI systems. Objective: We aimed to evaluate FluWatchers, a crowdsourced ILI application developed to complement and complete ILI surveillance in Canada. Methods: Using established frameworks for surveillance evaluations, we assessed the acceptability, reliability, accuracy and usefulness of the FluWatchers system 2015–2016, through 2018–2019. Evaluation indicators were compared against national surveillance indicators of ILI and of laboratory confirmed respiratory virus infections. Results: The acceptability of FluWatchers was demonstrated by growth of 50%–100% in season-over-season participation, and a consistent season-over-season retention of 80%. Reliability was greater for FluWatchers than for our traditional ILI system, although both systems had week-over-week fluctuations in the number of participants responding. FluWatchers’ ILI rates had moderate correlation with weekly influenza laboratory detection rates and other winter seasonal respiratory virus detections including respiratory syncytial virus and seasonal coronaviruses. Finally, FluWatchers has demonstrated its usefulness as a source of core FluWatch surveillance information and has the potential to fill data gaps in current programs for influenza surveillance and control. Conclusion: FluWatchers is an example of an innovative digital participatory surveillance program that was created to address limitations of traditional ILI surveillance in Canada. It fulfills the surveillance system evaluation criteria of acceptability, reliability, accuracy and usefulness.
Poly-freeness of Artin groups and the Farrell–Jones Conjecture
Authors: Wu Xiaolei
Published: September 2021

We provide two simple proofs of the fact that even Artin groups of FC-type are poly-free which was recently established by R. Blasco-Garcia, C. Martínez-Pérez and L. Paris.
More generally, let Γ be a finite simplicial graph with all edges labelled by positive even integers, and let

A
Γ

A_{\Gamma}

be its associated Artin group; our new proof implies that if

A
T

A_{T}

is poly-free (resp. normally poly-free) for every clique 𝑇 in Γ, then

A
Γ

A_{\Gamma}

is poly-free (resp. normally poly-free).
We prove similar results regarding the Farrell–Jones Conjecture for even Artin groups.
In particular, we show that if

A
Γ

A_{\Gamma}

is an even Artin group such that each clique in Γ either has at most three vertices, has all of its labels at least 6, or is the join of these two types of cliques (the edges connecting the cliques are all labelled by 2), then

A
Γ

A_{\Gamma}

satisfies the Farrell–Jones Conjecture.
In addition, our methods enable us to obtain results for general Artin groups.
The utility of continuous glucose monitoring systems in the management of children with persistent hypoglycaemia
Authors: Vijayanand Sathyakala , Stevenson Paul G. , Grant Maree , Choong Catherine S. , Davis Elizabeth A. , Abraham Mary B.
Published: September 2021

Objectives

Glucose monitoring is vital in children with persistent hypoglycaemia to reduce the risk of adverse neuro-behavioural outcomes; especially in children with hyperinsulinism. The role of continuous glucose monitoring (CGM) systems in monitoring glucose levels in this cohort is limited. The objective of this study was to ascertain the effectiveness of CGM and to evaluate parents’ experience of using CGM for monitoring glucose levels in children with hypoglycaemia.

Methods

Retrospective analysis of sensor glucose (SG) values from Dexcom G4 CGM with paired finger-prick blood glucose (BG) values was performed to determine the accuracy of CGM. The parent experience of CGM was assessed using a questionnaire administered to families of children with congenital hyperinsulinism currently attending the clinic.

Results

SG data from 40 children (median age 6 months) with persistent hypoglycaemia (60% Hyperinsulinism) were analysed. The mean difference between 5,650 paired BG and SG values was 0.28 mmol/L. The sensitivity and specificity of CGM to identify severe hypoglycaemia (BG < 3.0 mmol/L) were 54.3% (95% CI: 39.0%, 69.1%) and 97.4% (95% CI: 96.9%, 97.8%) respectively. Parents (n=11) reported less anxiety (n=9), better sleep at night (n=7) and preferred to use CGM for monitoring (n=9).

Conclusions

Although the high number of false-positive readings precludes the routine use of CGM in the evaluation of hypoglycaemia, it avoids unnecessary BG testing during normoglycaemia. It is an acceptable tool for parents for monitoring their children who are at risk of hypoglycaemia. Newer CGM systems with improved accuracy at lower glucose levels have the potential to further improve monitoring.
Diversity by Design: Improving Access to Justice in Online Courts with Adaptive Court Interfaces
Authors: Sela Ayelet
Published: September 2021

Recent years have seen the emergence of online courts and tribunals: digital platforms that enable self-represented litigants (SRLs) to complete electronically the entire court (or tribunal) process, from filing through final disposition. This article proposes that the unique nature of online courts as digital interfaces enables them to implement a new strategy—diversity by design—to improve access to justice and procedural justice for a diverse population of SRLs. Reflecting a human-centered legal design approach, and building on research in human-computer interaction and digital choice architecture, this strategy entails embedding diversity accommodating features in the technological design of court platforms. Specifically, building on the empirical relationship between users’ demographic attributes and their digital usability and aesthetics judgments, this article suggests that online courts can dynamically adapt their interfaces according to the attributes of a given user in ways that help diverse SRLs engage with online courts, support their effective participation in proceedings, and improve their procedural experiences. The potential impacts include enhancing SRLs’ confidence and trust in using online courts and ameliorating their ability to process information, deliberate, make informed decisions and communicate them. Finally, the article discusses concerns regarding the desirability and ethicality of dynamically adapting, that is—personalizing, court interfaces.
Tailoring of plasmonic functionalized metastructures to enhance local heating release
Authors: Ferraro Antonio , Lio Giuseppe Emanuele , Hmina Abdelhamid , Palermo Giovanna , Djouda Joseph Marae , Maurer Thomas , Caputo Roberto
Published: September 2021

Plasmonic nanoheaters are reported that produce a significant local heating when excited by a 532 nm wavelength focused laser beam. A significant temperature increase derives from the strong confinement of electric field enabled by the specific arrangement of Au nanodisks constituting the nanoheater. The thermal response is much more sensitive when layering the gold nanoheaters by a thick layer of doped polymer, reaching a temperature variation of more than 250 °C. The modulation of the excitation by a chopper enables the fine control of the thermal response with a measured maximum temperature variation of about 60 °C in a single period. These intriguing features can be efficiently exploited for the design of novel systems finding application in nano medicine and nano chemistry.
Evaluation of optimal urine screening and confirmation cut-off values for opiates, at a national reference laboratory
Authors: Karakükcü Çiğdem , Çıracı Mehmet Zahid , Kocer Derya , Faydalı Mine Yüce , Serdar Muhittin Abdulkadir
Published: September 2021

Objectives

To obtain optimal immunoassay screening and LC-MS/MS confirmation cut-offs for opiate group tests to reduce false positive (FP) and false negative (FN) rates.

Methods

A total of 126 urine samples, −50 opiate screening negative, 76 positive according to the threshold of 300 ng/mL by CEDIA method – were confirmed by a full-validated in-house LC-MS/MS method. Sensitivity, specificity, FP, and FN rates were determined at cut-off concentrations of both 300 and 2,000 ng/mL for morphine and codeine, and 10 ng/mL for heroin metabolite 6-mono-acetyl-morphine (6-MAM).

Results

All CEDIA opiate negative urine samples were negative for morphine, codeine and 6-MAM. Although sensitivity was 100% for each cut-off; specificity was 54.9% at CEDIA cut-off 300 ng/mL vs. LC-MS/MS cut-off 300 ng/mL and, 75% at CEDIA cut-off 2,000 ng/mL vs. LC-MS/MS cut-off 2,000 ng/mL. False positive rate was highest (45.1%) at CEDIA cut-off 300 ng/mL. At CEDIA cut-off 2,000 ng/mL vs. LC-MS/MS cut-off 300 ng/mL, specificity increased to 82.4% and FP rate decreased to 17.6%. All 6-MAM positive samples had CEDIA concentration ≥2,000 ng/mL.

Conclusions

2,000 ng/mL for screening and 300 ng/mL for confirmation cut-offs are the most efficient thresholds for the lowest rate of FP opiate results.