bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence and risk factors of endoscopically confirmed gastroesophageal reflux disease (GERD) in patients with liver cirrhosis
Authors: Hassanin Taha M. , Foaud Yasser , Mohamed Hala , Saad Zienab , Elsayed Amr , Refaei Sara , Soliman Wael
Published: April 2021

Background

Gastroesophageal reflux disease (GERD) is one of the most common diseases in modern civilization that originates basically from a disturbance in the structure and function of the lower esophageal sphincter (LES). Liver cirrhosis with or without esophageal varices (EV) may predispose to GERD, and GERD may precipitate rupture of esophageal varices. As variceal bleeding is a serious life-threatening complication of liver cirrhosis, GERD prevalence among cirrhotic patients is continuously subjected to research. We aimed to determine the prevalence of endoscopy-confirmed GERD in patients with liver cirrhosis and its possible risk factors. So, one hundred patients with HCV-related liver cirrhosis were consecutively enrolled in this study. They were subjected to history taking {including Reflux Disease Questionnaire}, thorough clinical examination, abdominal ultrasound, and lab investigations and then referred for upper endoscopy to screen for GERD and/or esophageal varices.

Results

GERD was endoscopically confirmed in 83 patients (83%) and the highest prevalence was in patients with Child B and C. Among 82 patients with esophageal varices, there were 68 patients who had endoscopic GERD (82.9%), and among 62 patients with ascites, there were 56 patients who had endoscopic GERD (90.3%).

Conclusion

We found a high prevalence of GERD (83%) among patients with liver cirrhosis. The severity of GERD was significantly related to the Child grade, the grade of varices, and the degree of ascites but ascites was the only significant risk factor for GERD development in cirrhotic patients.
Novel stability-indicating RP-UPLC method for simultaneous estimation of sitagliptin and ertugliflozin in bulk and pharmaceutical formulations
Authors: B Ramya kuber , Addanki Swetha
Published: April 2021

Background

The present investigation was proposed to develop a simple, sensitive, rapid, accurate, precise stability-indicating RP-UPLC method for simultaneous estimation of sitagliptin and ertugliflozin. Chromatographic separation was performed with Waters Hibar C8 [100×2.1mm, 2μ] column and mobile phase acetonitrile: water (pH 3.5) [50:50%, v/v], pumped at a flow rate 0.2ml/min. The separated analytes were detected with a UV detector at a wavelength of 218nm.

Results

The separation of sitagliptin and ertugliflozin was done at a retention time of 0.859min and 1.570min, respectively. The present method was validated according to the ICH guidelines Q2 R1, and stability-indicating studies were carried out as per ICH guidelines Q1A R2. Intra-day and inter-day precision were found to be within acceptable limits. The linearity of the proposed method was in the concentration range of 25–125μg/ml and 3.75–22.5μg/ml for sitagliptin and ertugliflozin, respectively. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.5μg/ml and 1.53μg/ml for sitagliptin and 0.13μg/ml and 0.38μg/ml for ertugliflozin, respectively. The recovery of the method was found in between 99.7% and 100.7%.

Conclusion

The proposed method was able to distinguish the analytes from by-products. Hence, the method was successfully implied for stability-indicating studies and for routine examination of sitagliptin and ertugliflozin in pharmaceutical formulation.
Predictors of persistence in patients with schizophrenia treated with aripiprazole once-monthly long-acting injection in the Spanish clinical practice: a retrospective, observational study
Authors: Olivares José Manuel , González-Pinto Ana , Páramo Mario
Published: April 2021

Background

Poor adherence to antipsychotic drugs is a major problem in schizophrenia management and one of the most important risk factors for relapse and hospitalization. To date, there is little evidence on persistence predictors with long-acting injectable antipsychotics, especially with aripiprazole once-monthly (AOM). This study (NCT03130478) aimed to describe the impact of demographic and clinical characteristics on persistence with AOM treatment in real-world setting.

Methods

This was an observational, retrospective, non-interventional study that included adult patients with schizophrenia who were initiated on AOM during a schizophrenia-related hospitalization. Data were retrospectively collected from patients’ medical records. The primary variable was persistence with AOM, measured as the number of days from AOM initiation up to all-cause AOM discontinuation during the first six months after treatment index.

Results

140 patients were enrolled and 91 fulfilled the selection criteria. Six months after AOM initiation, 65 (71.4%) patients were still receiving AOM treatment, whereas 26 (28.6%) were not. The mean (standard deviation) time to AOM treatment discontinuation in the first six months was 138.1 (6.8) days, with most of the patients discontinuing at the first 28 days. The risk of AOM discontinuation in the first six months increases 1.05-fold annually since schizophrenia diagnosis (p=0.003); moreover, this risk increases 2.86-fold in patients with concomitant schizophrenia medication at AOM initiation compared to patients without concomitant schizophrenia treatments (p=0.02).

Conclusions

Main factors predicting persistence with AOM treatment at six months in clinical practice are fewer years since schizophrenia diagnosis and not receiving concomitant schizophrenia treatments at AOM initiation.
Perioperative high dose rate brachytherapy in head and neck cancers: case report and review of clinical application
Authors: Bahl Amit , Verma Roshan K , Panda Naresh K , Oinam Arun S , John Jerry R , Kaur Satinder , Kumar Pramod , Ghoshal Sushmita , Trivedi Gaurav , Bakshi Jaimanti
Published: April 2021

Perioperative high dose rate brachytherapy is a radiotherapy treatment technique which involves intraoperative insertions of brachytherapy catheters into the tumor bed during the surgical resection followed by treatment in the post-operative period. We report here two cases to highlight its use in the primary treatment and reirradiation of head and neck cancers.
An optimized fixation method containing glyoxal and paraformaldehyde for imaging nuclear bodies
Authors: Yao Run-Wen , Luan Peng-Fei , Chen Ling-Ling
Published: April 2021

The mammalian cell nucleus contains different types of membrane-less nuclear bodies (NBs) consisting of proteins and RNAs. Microscopic imaging has been widely applied to study the organization and structure of NBs. However, current fixation methods are not optimized for such imaging: When a fixation method is chosen to maximize the quality of the RNA fluorescence in situ hybridization (FISH), it often limits the labeling efficiency of proteins or affects the ultrastructure of NBs. Here, we report that addition of glyoxal (GO) into the classical paraformaldehyde (PFA) fixation step not only improves FISH signals for RNAs in NBs via augmented permeability of the fixed nucleus and enhanced accessibility of probes, but also largely preserves protein fluorescent signals during fixation and immunostaining. We also show that GO/PFA fixation enables the covisualization of different types of nuclear bodies with minimal impact on their ultrastructures under super-resolution microscopy.
Το πρόβλημα της ρωγμής εις τον "γενικώς" ανισότροπον δίσκον
Authors: Γαλιδάκης Νικόλαος
Published: April 2021

C'est connu (Muskhelishvili) qu'un problème de théorie mathématique de Γ Elasticité isotrope, se laisse résoudre par des fonctions de forme fermée, pourvu que la fonction qui représente cuinformcmeiit te dommaine considéré, dans ou dehors le cercle unitaire, soit une fonction rationelle. Dans le present ouvrage, le théorème ci - dessus, est généralisé pour le cas de Γ anisotropie «generale» dans lequel existent trois fonctions de configuration, qui ne doivent pas être seulement rationelles, mais en plus, être liées par la condition (20). ßur la base ci-dessus, s' aborde un problème fondamental, ou est envisagé comme «domaine» le disque élastique anisotrope infini, qui présente une coupe rectiligne le longueur 2R. (Cette coupe est d' ailleurs considérée comme le perigramme du disque). Les fonctions de potentiel complex sont établies pour les trois cas distincts de sollicitation qui suivent : a) Pour des tensions données, très éloignées du perigramme b) Pour une charge partielle normale au perigramme, et c) Pour une charge tangentielle au perigramme. Par de transfert convenable à la limite, (par rapport au perigramme pu à la sollicitation), toutes les solutions connues, ou presque connues, qui concernent le demi - espace anisotrope sont déduites. Enfin des résultats utiles sont extradés, concernant Y application de la recherche sur les fonctions de potentiel complex à la conduite du materiel anisotrope pour les cas de sollicitation différents.
PUblications Metadata Augmentation (PUMA) pipeline
Authors: Butters Oliver W. , Wilson Rebecca C. , Garner Hugh , Burton Thomas W. Y.
Published: April 2021

Cohort studies collect, generate and distribute data over long periods of time – often over the lifecourse of their participants. It is common for these studies to host a list of publications (which can number many thousands) on their website to demonstrate the impact of the study and facilitate the search of existing research to which the study data has contributed. The ability to search and explore these publication lists varies greatly between studies.

We believe a lack of rich search and exploration functionality of study publications is a barrier to entry for new or prospective users of a study’s data, since it may be difficult to find and evaluate previous work in a given area. These lists of publications are also typically manually curated, resulting in a lack of rich metadata to analyse, making bibliometric analysis difficult.

We present here a software pipeline that aggregates metadata from a variety of third-party providers to power a web based search and exploration tool for lists of publications. Alongside core publication metadata (i.e. author lists, keywords etc.), we include geocoding of first authors and citation counts in our pipeline. This allows a characterisation of a study as a whole based on common locations of authors, frequency of keywords, citation profile etc. This enriched publications metadata can be useful for generating study impact metrics and web-based graphics for public dissemination. In addition, the pipeline produces a research data set for bibliometric analysis or social studies of science. We use a previously published list of publications from a cohort study as an exemplar input data set to show the output and utility of the pipeline here.
Experimental Study on Sugarcane Top Chopper
Authors: Hu Jiwei , Ma Shaochun , Gao Shili , Bai Jing , Wang Fenglei , Xing Haonan
Published: April 2021

Highlights

This article focuses on the sugarcane top chopper.

The influence of three factors on the experimental indexes was studied.

The optimal parameters combination of working performance was obtained.

Abstract. In the process of sugarcane harvesting, sugarcane tops are cut off by the chopper and directly thrown into the field. A small percentage of sugarcane tops are picked and collected to feed livestock. Therefore, it is meaningful to develop an effective sugarcane top chopper which is used to harvest sugarcane tops before harvesting sugarcane stalk harvesting. In this study, a sugarcane top chopping platform was fabricated to investigate critical parameters such as chopping speed (CS), top feeding speed (FS), and cutting drum gap (DG) on the machine performance. In evaluating the sugarcane top chopper, three single factor experiment and one orthogonal experiment were carried out. The single factor test was used to examine the effect of CS, FS and DG on the chopping performance of the machine. According to orthogonal test, the comprehensive influence order was determined: cutting drum gap > chopping speed > top feeding speed. The optimal parameters combination for good working performance of the machine was obtained: chopping speed was 750 rpm, top feeding speed was 1.2 m·s-1, and cutting drum gap was 20 mm. The relationships between the chopping performance and the three critical factors were examined and analyzed to provide theoretical basis for the development of a sugarcane top chopper. Keywords: Chopping performance, Orthogonal test, Single factor test, Sugarcane top chopper, Variance analysis.
Flexible, fast, and benchmarked vectorial model for focused laser beams
Authors: Li Qingfeng , Chambonneau Maxime , Blothe Markus , Gross Herbert , Nolte Stefan
Published: April 2021

In-bulk processing of materials by laser radiation has largely evolved over the last decades and still opens up new scientific and industrial potentials. The development of any in-bulk processing application relies on the knowledge of laser propagation and especially the volumetric field distribution near the focus. Many commercial programs can simulate this, but, to adapt them, or to develop new methods, one usually must create a specific software. Besides, most of the time people also need to measure the actual field distribution near the focus to evaluate their assumptions in the simulation. To easily get access to this knowledge, we present our high-precision field distribution measuring method and release our in-house software InFocus [https://github.com/QF06/InFocus], under the Creative Commons 4.0 license. Our measurements provide 300 nm longitudinal resolution and diffraction limited lateral resolution. The in-house software allows fast vectorial analysis of the focused volumetric field distribution in bulk. Simulations of the linear propagation of light under different conditions (focusing optics, wavelength, spatial shape, and propagation medium) are in excellent agreement with propagation imaging experiments. The aberrations provoked by the refractive index mismatch as well as those induced by the focusing optics are both taken into account. The results indicate that our proposed model is suitable for the precise evaluation of energy deposition.
Reducing the effects of parallax in camera-based pulse-oximetry
Authors: van Gastel Mark , Wang Wenjin , Verkruysse Wim
Published: April 2021

Camera-based pulse-oximetry enables contactless estimation of peripheral oxygen saturation (SpO2). Because of the lack of readily available and affordable single-optics multi-spectral cameras, custom-made multi-camera setups with different optical filters are currently mostly used. The introduced parallax by these cameras could however jeopardise the SpO2 algorithm assumptions, especially during subject movement. In this paper we investigate the effect of parallax quantitatively by creating a large dataset consisting of 150 videos with three different parallax settings and with realistic and challenging motion scenarios. We estimate oxygen saturation values with a previously used global frame registration method and with a newly proposed adaptive local registration method to further reduce the parallax-induced image misalignment. We found that the amount of parallax has an important effect on the accuracy of the SpO2 measurement during movement and that the proposed local image registration reduces the error by more than a factor of 2 for the most common motion scenarios during screening. Extrapolation of the results suggests that the error during the most challenging motion scenario can be reduced to approximately 2 percent when using a parallax-free single-optics camera. This study provides important insights on the possible applications and use cases of remote pulse-oximetry with current affordable and readily available cameras.
Unambiguous derivation of the effective refractive index of biological suspensions and an extension to dense tissue such as blood
Authors: Nahmad-Rohen Alexander , García-Valenzuela Augusto
Published: April 2021

The van de Hulst formula provides an expression for the effective refractive index or effective propagation constant of a suspension of particles of arbitrary shape, size, and refractive index in an optically homogeneous medium. However, its validity for biological matter, which often consists of very dense suspensions of cells, is unclear because existing derivations of the formula or similar results rely on far-field scattering and/or on the suspension in question being dilute. We present a derivation of the van de Hulst formula valid for suspensions of large, tenuous scatterers—the type biological suspensions are typically made of—that does not rely on these conditions, showing that they are not strictly necessary for the formula to be valid. We apply these results specifically to blood and epithelial tissue. Furthermore, we determine the true condition for the formula to be valid for these types of tissues. We finally provide a simple way to estimate—and, more importantly, correct—the error incurred by the van de Hulst formula when this condition is not met.
Efficient simulation of biperiodic, layered structures based on the T-matrix method
Authors: Beutel Dominik , Groner Achim , Rockstuhl Carsten , Fernandez-Corbaton Ivan
Published: April 2021

Predicting the optical response of macroscopic arrangements of individual scatterers is a computational challenge because the problem involves length scales across multiple orders of magnitude. We present a full-wave optical method to efficiently compute the scattering of light at objects that are arranged in biperiodic arrays. Multiple arrays or homogeneous thin films can be stacked to build up an entire multicomposite material in the third dimension. The scattering properties of the individual objects in each array are described by the T-matrix formalism. Therefore, arbitrarily shaped objects and even molecules can be the basic constituent of the arrays. Taking the T-matrix of the individual scatterer as the point of departure we can explain the optical properties of the bulk material from the scattering properties of its constituents. We use solutions of Maxwell’s equations with well-defined helicity. Therefore, chiral media are particularly easy to consider as materials for both scatterers and embedding media. We exemplify the efficiency of the algorithm with an exhaustive parametric study of anti-reflective coatings for solar cells made from cylinders with a high degree of helicity preservation. The example shows a speed-up factor of about 500 with respect to finite-element computations. A second example specifically exploits the use of helicity modes to investigate the enhancement of the circular dichroism signal in a chiral material.
Fast computation of scattering by isolated defects in periodic dielectric media
Authors: Virk Kuljit S.
Published: April 2021

Scattering by an isolated defect embedded in a dielectric medium of two-dimensional periodicity is of interest in many sub-fields of electrodynamics. Present approaches to compute this scattering rely on either the Born approximation and its quasi-analytic extensions or ab initio computation that requires large domain sizes to reduce the effects of boundary conditions. The Born approximation and its extensions are limited in scope, while the ab initio approach suffers from its high numerical cost. In this paper, I introduce a hybrid scheme in which an effective local electric susceptibility tensor of a defect is estimated by solving an inverse problem efficiently. The estimated tensor is embedded into an S-matrix formula based on the reciprocity theorem. With this embedding, the computation of the S-matrix of the defect requires field solutions only in the unit cell of the background. In practice, this scheme reduces the computational cost by almost two orders of magnitude, while sacrificing little in accuracy. The scheme demonstrates that statistical estimation can capture sufficient information from cheap calculations to compute quantities in the far field. I outline the fundamental theory and algorithms to carry out the computations in high dielectric contrast materials, including metals. I demonstrate the capabilities of this approach with examples from optical inspection of nano-electronic circuitry where the Born approximation fails and the existing methods for its extension are also inapplicable.
Planar refractive lenses made of SiC for high intensity nanofocusing
Authors: Lyubomirskiy Mikhail , Schurink Bart , Makhotkin Igor A. , Brueckner Dennis , Wittwer Felix , Kahnt Maik , Seyrich Martin , Seiboth Frank , Bijkerk Fred , Schroer Christian G.
Published: April 2021

We report on the manufacturing and testing of the first nanofocusing refractive lenses made of single-crystal silicon carbide. We introduce the fabrication process based on lithography, followed by deep isotropic etching. The lenses were characterized at the energy of 12 keV at the beamline P06 of the synchrotron radiation source PETRA III. A focal spot of 186 nm×275 nm has been achieved with a lens working distance of 29 mm.
Theory of microscopic semiconductor lasers with external optical feedback
Authors: Rasmussen Thorsten S. , Mork Jesper
Published: April 2021

The properties of microscopic semiconductor lasers with external optical feedback are theoretically analysed. The size-dependence of the critical feedback level, at which the laser first becomes unstable, is clarified, showing how the dominant indicator of feedback stability is the gain of the laser, irrespective of size. The impact of increased spontaneous emission β-factors and over-damped operation is evaluated, exposing a diminished phase sensitivity of microscopic lasers, and a trade-off between modulation bandwidth and feedback stability is identified.
RISE: robust iterative surface extension for sub-nanometer X-ray mirror fabrication
Authors: Wang Tianyi , Huang Lei , Choi Heejoo , Vescovi Matthew , Kuhne Denis , Zhu Yi , Pullen Weslin C. , Ke Xiaolong , Kim Dae Wook , Kemao Qian , Tayabaly Kashmira , Bouet Nathalie , Idir Mourad
Published: April 2021

Precision optics have been widely required in many advanced technological applications. X-ray mirrors, as an example, serve as the key optical components at synchrotron radiation and free electron laser facilities. They are rectangular silicon or glass substrates where a rectangular Clear Aperture (CA) needs to be polished to sub-nanometer Root Mean Squared (RMS) to keep the imaging capability of the incoming X-ray wavefront at the diffraction limit. The convolutional polishing model requires a CA to be extended with extra data, from which the dwell time is calculated via deconvolution. However, since deconvolution is very sensitive to boundary errors and noise, the existing surface extension methods can hardly fulfill the sub-nanometer requirement. On one hand, the figure errors in a CA were improperly modeled during the extension, leading to continuity issues along the boundary. On the other hand, uncorrectable high-frequency errors and noise were also extended. In this study, we propose a novel Robust Iterative Surface Extension (RISE) method that resolves these problems with a data fitting strategy. RISE models the figure errors in a CA with orthogonal polynomials and ensures that only correctable errors are fit and extended. Combined with boundary conditions, an iterative refinement of dwell time is then proposed to compensate the errors brought by the extension and deconvolution, which drastically reduces the estimated figure error residuals in a CA while the increase of total dwell time is negligible. To our best knowledge, RISE is the first data fitting-based surface extension method and is the first to optimize dwell time based on iterative extension. An experimental verification of RISE is given by fabricating two elliptic cylinders (10 mm × 80 mm CAs) starting from a sphere with a radius of curvature around 173 m using ion beam figuring. The figure errors in the two CAs greatly improved from 204.96 nm RMS and 190.28 nm RMS to 0.62 nm RMS and 0.71 nm RMS, respectively, which proves that RISE is an effective method for sub-nanometer level X-ray mirror fabrication.
Tunable quantum two-photon interference with reconfigurable metasurfaces using phase-change materials
Authors: Estakhri Nooshin M. , Norris Theodore B.
Published: April 2021

The ability of phase-change materials to reversibly and rapidly switch between two stable phases has driven their use in a number of applications such as data storage and optical modulators. Incorporating such materials into metasurfaces enables new approaches to the control of optical fields. In this article we present the design of novel switchable metasurfaces that enable the control of the nonclassical two-photon quantum interference. These structures require no static power consumption, operate at room temperature, and have high switching speed. For the first adaptive metasurface presented in this article, tunable nonclassical two-photon interference from −97.7% (anti-coalescence) to 75.48% (coalescence) is predicted. For the second adaptive geometry, the quantum interference switches from −59.42% (anti-coalescence) to 86.09% (coalescence) upon a thermally driven crystallographic phase transition. The development of compact and rapidly controllable quantum devices is opening up promising paths to brand-new quantum applications as well as the possibility of improving free space quantum logic gates, linear-optics bell experiments, and quantum phase estimation systems.
Complex spectral filters in silicon waveguides based on cladding-modulated Bragg gratings
Authors: Pereira-Martín Daniel , Luque-González José Manuel , Gonzalo Wangüemert-Pérez J. , Hadij-ElHouati Abdelfettah , Molina-Fernández Íñigo , Cheben Pavel , Schmid Jens H. , Wang Shurui , Ye Winnie N. , Čtyroký Jiří , Ortega-Moñux Alejandro
Published: April 2021

Spectral filters are important building blocks for many applications in integrated photonics, including datacom and telecom, optical signal processing and astrophotonics. Sidewall-corrugated waveguide grating is typically the preferred option to implement spectral filters in integrated photonic devices. However, in the high-index contrast silicon-on-insulator (SOI) platform, designs with corrugation sizes of only a few tens of nanometers are often required, which hinders their fabrication. In this work, we propose a novel geometry to design complex Bragg filters with an arbitrary spectral response in silicon waveguides with laterally coupled Bragg loading segments. The waveguide core is designed to operate with a delocalized mode field, which helps reduce sensitivity to fabrication errors and increase accuracy on synthesized coupling coefficients and the corresponding spectral shape control. We present an efficient design strategy, based on the layer-peeling and layer-adding algorithms, that allows to readily synthesize an arbitrary target spectrum for our cladding-modulated Bragg gratings. The proposed filter concept and design methodology are validated by designing and experimentally demonstrating a complex spectral filter in an SOI platform, with 20 non-uniformly spaced spectral notches with a 3-dB linewidth as small as 210 pm.
Impact of industrial environments on visible light communication
Authors: Schneider Daniel , Shrotri Abhijeet , Flatt Holger , Stübbe Oliver , Wolf Alexander , Lachmayer Roland , Bunge Christian-Alexander
Published: April 2021

Visible-light communication is a promising technology for industrial environments. However, a variety of physical effects may influence the communication quality in this potentially harsh environment: Dust and other particles lead to increased attenuation. Artificial light sources and industrial processes, such as grinding and welding, cause optical cross-talk. A multitude of reflective surfaces can lead to fading due to multi-path propagation. These three aspects are experimentally investigated in exemplary manufacturing processes at five different production sites in order to estimate the relative importance and their specific impact on VLC transmission in industrial areas. Spectral measurements demonstrate the presence of interfering light sources, which occupy broad parts of the visible spectrum. They give rise to flickering noise, which comprises a set of frequencies in the electrical domain. The impact of these effects on the communication is analysed with reference to the maximum achievable channel capacity and data rate approximation based on on-off keying is deduced. It is found that cross-talk by environmental and artificial light sources is one of the strongest effects, which influences the optical, but also the electrical spectrum. It is also observed that industrial areas differ strongly and must be categorised according to the manufacturing processes, which can induce quite a variation of dust and attenuation accordingly.
Numerical modeling of a hybrid hollow-core fiber for enhanced mid-infrared guidance
Authors: Hayashi Juliano G. , Mousavi Seyed M. A. , Ventura Andrea , Poletti Francesco
Published: April 2021

We propose a novel design of hollow-core fiber for enhanced light guidance in the mid-infrared. The structure combines an arrangement of non-touching antiresonant elements in the air core with a multilayer glass/polymer structure in the fiber’s cladding. Through numerical modeling, we demonstrate that the combination of antiresonant/inhibited-coupling and photonic bandgap guidance mechanisms can decrease the optical loss of a tubular antiresonant fiber by more than one order of magnitude. More specifically, our simulations demonstrate losses of the HE11 mode in the few dB/km level, which can be tuned through mid-infrared wavelengths (5 µm-10.6 µm) by carefully optimizing the structural parameters of both structures. We also show that the hybrid hollow-core fiber design is more robust to bend-induced loss than an equivalent tubular antiresonant fiber or a Bragg/OmniGuide fiber. As a result, if successfully fabricated, the hybrid hollow-core fiber will offer low-loss, high beam-quality, effectively single-mode operation, and low bending losses, potentially solving many of the problems that affect all known mid-infrared fiber types.
Optical metasurface composed of multiple antennas with anti-Hermitian coupling in a single layer
Authors: Shi Xi , Ge Lixin , Liu Boyuan , Xu Hao , Cao Duo , Liu Feng
Published: April 2021

Metasurfaces consisting of different shapes of resonant units are used to manipulate light beams at subwavelength scales. In many cases, interactions among the resonant units are suppressed or avoided because of mode splitting in metasurfaces. Here we theoretically and numerically investigate metasurfaces composed of multiple antennas with anti-Hermitian coupling in a single layer. By utilizing the anti-Hermitian coupling, the results show that antennas with similar resonance frequencies at a subwavelength distance can individually absorb their corresponding frequency photons. The antennas whose reflection phase can be tailored by changing the number of antennas have the same resonance frequencies. This Letter paves the way for various potential applications in broadband absorption, photon sorting, image sensors, and phase modulation.
Generation of hyper-entangled states in strongly coupled topological defects
Authors: Bergamasco Nicola , Sipe J. E. , Liscidini Marco
Published: April 2021

We investigate spontaneous parametric downconversion (SPDC) in a
waveguide array supporting two strongly coupled topological guided
modes. We show that it is possible to generate photon pairs that are
hyper-entangled in energy and path. We study the state robustness
against positional disorder of the waveguides, in terms of Schmidt
number (SN), fidelity, and density matrix. We show that quantum
correlations are in general robust due to the peculiar interplay
between structure topology and second-order nonlinear interaction.
Environmentally robust immersion supercritical lens with an invariable sub-diffraction-limited focal spot
Authors: Zhang Zhaoxia , Li Zhangyin , Lei Jian , Wu Jin , Zhang Kun , Wang Sicong , Cao Yaoyu , Qin Fei , Li Xiangping
Published: April 2021

Planar metalenses provide an effective way to break the diffraction barrier in the far field. Their physical mechanism and applications have been intensively studied in the past decade. These investigations on sub-diffraction-limited light modulations have only been applied to specified single immersion environments; however, changing immersion environments can severely degrade their focusing performance, limiting their application potential. In this work, we propose and experimentally demonstrate an environmentally robust immersion supercritical lens (SCL) that can work in various immersion environments. The design of such a lens is based on the vectorial Rayleigh–Sommerfeld diffraction theory combined with a multi-objective optimization algorithm. The sub-diffraction-limited focusing effect has been experimentally demonstrated in commonly used media, including air, water, and oil, with refractive indices of 1.0, 1.33, and 1.51, respectively. Moreover, such a lens can maintain its effective numerical aperture at a fixed value, bringing a unique advantage in that the lateral size of the focal spots exhibits a similar value of

317

±

7

n
m

in all three media. Our demonstration provides the feasibility of SCLs in various application scenarios with multi-immersion environments, such as bioimaging, light trapping, and optical storage.
How large is the quantum enhancement of two-photon absorption by time-frequency entanglement of photon pairs?
Authors: Raymer Michael G. , Landes Tiemo , Allgaier Markus , Merkouche Sofiane , Smith Brian J. , Marcus Andrew H.
Published: April 2021

We present a theoretical proof that the “quantum enhancement” of two-photon absorption, thought to be a means to improve molecular spectroscopy and imaging, is tightly bounded by the physics of photonic entanglement and nonlinear response.
Prevalence of stunting and associated factors among public primary school pupils of Bahir Dar city, Ethiopia: School-based cross-sectional study
Authors: Bantie Getasew Mulat , Aynie Amare Alamirew , Akenew Kidist Hailu , Belete Mahlet Tilahun , Tena Eyerusalem Teshome , Gebretsadik Genet Gebreselasie , Tsegaw Aynalem Nebebe , Woldemariam Tigist Birru , Woya Ashenafi Abate , Melese Amare Alemu , Ayalew Agumas Fentahun , Dessie Getenet
Published: April 2021

Background

Stunting is a well-established child-health indicator of chronic malnutrition, which reliably gives a picture of the past nutritional history and the prevailing environmental and socioeconomic circumstances.

Objective

To investigate the prevalence of stunting and associated factors among public primary school children of the Bahir Dar city.

Method

A cross-sectional study was carried out from March to June 2019. Data were coded and entered into the Epi-Data and exported to SPSS version 23 software. The pupil was stunted if the height- for-age was ≤ -2 SDs from the median growth standards according to the WHO. A descriptive summary was computed using frequency, percent, mean, median and standard deviation. A simple logistic regression model was fitted to identify associated factors between the independent variables and the dependent variable at a 95% confidence interval (CI) and p-value <0.05.

Results

370 primary school pupils were included in the study with the mean age of 10.15 (± 2.23 SD) years. 51.6% of the pupils were females. The total prevalence of stunting was 15.13% (95%CI; 11%, 19%). The burden of stunting was higher in the age group of 11 years and older. Pupil’s age older than 11 years (AOR = 15. 6; 95%CI; 3.31, 73.45; p-value < 0. 001) and male sex (AOR = 7. 07; 95%CI: 2.51, 19.89; p-value < 0. 0002) were significantly associated with stunting.

Conclusion

The prevalence of stunting was relatively lower than the regional estimated stunting level. Older age and male sex were significantly associated with stunting.
Recommending encounters according to the sociodemographic characteristics of patient strata can reduce risks from type 2 diabetes
Authors: Ye Han , Mukherjee Ujjal Kumar , Chhajed Dilip , Hirsbrunner Jason , Roloff Collin
Published: April 2021

Objectives

Physician encounters with patients with type 2 diabetes act as motivation for self-management and lifestyle adjustments that are indispensable for diabetes treatment. We elucidate the sociodemographic sources of variation in encounter usage and the impact of encounter usage on glucose control, which can be used to recommend encounter usage for different sociodemographic strata of patients to reduce risks from Type 2 diabetes.

Data and methods

We analyzed data from a multi-facility clinic in the Midwestern United States on 2124 patients with type 2 diabetes, from 95 ZIP codes. A zero-inflated Poisson model was used to estimate the effects of various ZIP-code level sociodemographic variables on the encounter usage. A multinomial logistic regression model was built to estimate the effects of physical and telephonic encounters on patients’ glucose level transitions. Results from the two models were combined in marginal effect analyses.

Results and conclusions

Conditional on patients’ clinical status, demographics, and insurance status, significant inequality in patient encounters exists across ZIP codes with varying sociodemographic characteristics. One additional physical encounter in a six-month period marginally increases the probability of transition from a diabetic state to a pre-diabetic state by 4.3% and from pre-diabetic to the non-diabetic state by 3.2%. Combined marginal effect analyses illustrate that a ZIP code in the lower quartile of high school graduate percentage among all ZIP codes has 1 fewer physical encounter per six months marginally compared to a ZIP code at the upper quartile, which gives 5.4% average increase in the probability of transitioning from pre-diabetic to diabetic. Our results suggest that policymakers can target particular patient groups who may have inadequate encounters to engage in diabetes care, based on their immediate environmental sociodemographic characteristics, and design programs to increase their encounters to achieve better care outcomes.
In vivo assessment of a delayed release formulation of larazotide acetate indicated for celiac disease using a porcine model
Authors: Enomoto Hiroko , Yeatts James , Carbajal Liliana , Krishnan B. Radha , Madan Jay P. , Laumas Sandeep , Blikslager Anthony T. , Messenger Kristen M.
Published: April 2021

There is no FDA approved therapy for the treatment of celiac disease (CeD), aside from avoidance of dietary gluten. Larazotide acetate (LA) is a first in class oral peptide developed as a tight junction regulator, which is a lead candidate for management of CeD. A delayed release formulation was tested in vitro and predicted release in the mid duodenum and jejunum, the target site of CeD. The aim of this study was to follow the concentration versus time profile of orally administered LA in the small intestine using a porcine model. A sensitive liquid chromatography/tandem mass spectrometry method was developed to quantify LA concentrations in porcine intestinal fluid samples. Oral dosing of LA (1 mg total) in overnight fasted pigs resulted in time dependent appearance of LA in the distal duodenum and proximal jejunum. Peak LA concentrations (0.32–1.76 μM) occurred at 1 hour in the duodenum and in proximal jejunum following oral dosing, with the continued presence of LA (0.02–0.47 μM) in the distal duodenum and in proximal jejunum (0.00–0.43 μM) from 2 to 4 hours following oral dosing. The data shows that LA is available in detectable concentrations at the site of CeD.
Non-invasive adapted N-95 mask sampling captures variation in viral particles expelled by COVID-19 patients: Implications in understanding SARS-CoV2 transmission
Authors: Sriraman Kalpana , Shaikh Ambreen , Parikh Swapneil , Udupa Shreevatsa , Chatterjee Nirjhar , Shastri Jayanthi , Mistry Nerges
Published: April 2021

Infectious respiratory particles expelled by SARS-CoV-2 positive patients are attributed to be the key driver of COVID-19 transmission. Understanding how and by whom the virus is transmitted can help implement better disease control strategies. Here we have described the use of a noninvasive mask sampling method to detect and quantify SARS-CoV-2 RNA in respiratory particles expelled by COVID-19 patients and discussed its relationship to transmission risk. Respiratory particles of 31 symptomatic SARS-CoV-2 positive patients and 31 asymptomatic healthy volunteers were captured on N-95 masks layered with a gelatin membrane in a 30-minute process that involved talking/reading, coughing, and tidal breathing. SARS-CoV-2 viral RNA was detected and quantified using rRT-PCR in the mask and in concomitantly collected nasopharyngeal swab (NPS) samples. The data were analyzed with respect to patient demographics and clinical presentation. Thirteen of 31(41.9%) patients showed SARS-COV-2 positivity in both the mask and NPS samples, while 16 patients were mask negative but NPS positive. Two patients were both mask and NPS negative. All healthy volunteers except one were mask and NPS negative. The mask positive patients had significantly lower NPS Ct value (26) compared to mask negative patients (30.5) and were more likely to be rapid antigen test positive. The mask positive patients could be further grouped into low emitters (expelling <100 viral copies) and high emitters (expelling >1000 viral copies). The study presents evidence for variation in emission of SARS-CoV-2 virus particles by COVID-19 patients reflecting differences in infectivity and transmission risk among individuals. The results conform to reported secondary infection rates and transmission and also suggest that mask sampling could be explored as an effective tool to assess individual transmission risks, at different time points and during different activities.
Water footprint of protein yield of field crop species based on evapotranspiration patterns
Authors: Jolánkai Márton , Kassai Katalin M. , Eser Adna , Kempf Laura , Tarnawa Ákos
Published: April 2021

Water availability is one of the major physiological factors influencing plant growth and development.  An assessment study has been done at the Szent István University, Gödöllő to evaluate and identify the water footprint of protein yield of field crop species.

Six field crop species (sugar beet Beta vulgaris, winter barley Hordeum vulgare, winter wheat Triticum aestivum, maize Zea mays, potato Solanum tuberosum, and alfalfa Medicago sativa) were involved in the study. Evapotranspiration patterns of the crops studied have been identified and physiologically reliable protein ranges within crop yields were evaluated.

The results obtained suggest, that water footprint of cereals proved to be the lowest, however maize values were highly affected by the high variability of protein yield. Alfalfa, potato and sugar beet water footprints were in accordance with their evapotranspiration patterns.
The effect of different weed control technologies on weed species composition of maize
Authors: Vaczkó Gábor , Hódi László , Tar Melinda , Jakab Péter , Kristó István
Published: April 2021

In our investigation we used different weed control technologies in the different phenology states of the maize. The farm experiment has been carried out in Hungary, Kunágota, on flat surface, homogeneous quality chernozem soil, on 1000 m2 plots, in 4 replications.

The experiment can be regarded as 9 weed-control strategies where, in addition to the untreated control, two chemicals are applied (Laudis, Capreno) in different doses, two mechanical weed-control technologies, and two combination of chemicals and mechanicals weed-control technologies were used. Mechanical weed-control place connected to the herbicide treatments in different times: until 4-6-leave age weedless, in 4-6-leave age hoed once, in 4-6-leave age cultivation once.

Our results were assessed by chemical efficiency examination in five periods. Our resoult show that the two tested herbicides were efficient against weeds. Laudis was more effective, than Capreno against Setaria pumila. The dose enlargement of Capreno only slightly increased the herbicidal efficiency. The decreased dosage of Capreno was not efficient enough against Abutilon theophrasti.
Effects of different casing onto the yield of button mushroom
Authors: Szukács Gergely , Geösel András
Published: April 2021

In Europe and Hungary Agaricus bisporus is the most widely cultivated mushroom. Because of the competition on the market and the increasing costs of production is necessary to optimize the cultivation conditions and develop its intensive production technologies. The casing of the substrate is a critical and essential part of the intensive cultivaion technologies. The casing layer is important because it helps to protect the substrate from some pathogens and also balances the alternating temperature. More than 90% of the button mushroom fruitbody is water and thus mainly supplied by the casing. This casing soil contains the essential microbiota for primordia formation like Pseudomonas putida which has an important role in pin head stage. Casing soils origine from different source, mainly bogs or fens. The major component of casing soil is usually some kind of peat, like Sphagnum peat or black peat and lime. There is many contradiction about the effect of this casing soils onto the mushroom production during cultivation. In this study, we collected 7 different casing soils from farmers and casing soil producers (1 Dutch, 2 Polish, 2 Romanian and 2 Hungarian) and monitored the changes of its electric conductivity (EC) and pH during a small-scale cultivation, and examined this casings effects onto the yield. According our experiment the pH had been decreasing and the electric conductivity had been increasing during the cultivation. There were no significant differences between the casings in the total yield, but our results underlined that quality of casing has a major importance in the mushroom cultivation.
Enhanced biodegradability of dairy sludge by microwave assisted alkaline and acidic pre-treatments
Authors: Beszédes Sándor , Jákói Zoltán , Lemmer Balázs , Hodúr Cecilia
Published: April 2021

Considering the rapid, volumetric and selective heating effects of microwaves the microwave assisted chemical methods could provide appropriate alternatives for conventional thermal methods in sludge processing. Microwave irradiation alone is suitable to accelerate the hydrolysis stage of anaerobic decomposition of sludge resulted in accelerated biogas production rate and in higher biogas yield. Alkaline pre-treatments increase the organic matter solubility and suitable for disintegration of sludge particles. In some study are concluded that acidic conditions help the disintegration of waste activated sludge and assist in the solubilisation of carbohydrates and proteins which led to increased higher biogas production, as well. Beside the promising results related to effects of microwave pre-treatments on anaerobic digestion of sludge there are very few reports on the investigation of combined acidic/alkali-microwave pre-treatment method for food industry originated sludge. Hence, our study focused on the examination of the effects of combined microwave-alkali and microwave-acidic pre-treatment on aerobic and anaerobic biodegradability of sludge produced in dairy industry

Our experimental results verified, that microwave irradiation with alkaline dosage improve the solubility of organic matters in the pH range of 8-12. But enhancement of disintegration was not correlated linearly with biodegradability. During pre-treatment stage, applying pH over 10, the aerobic biodegradability show decreasing tendency. Applying of acidic condition during microwave irradiation resulted in lower disintegration degree than obtained for microwave-alkaline sludge pre-treatment method. But with microwave assisted acidic pre-treatments a higher aerobic biodegradability could be achieved than with alkaline dosage. In microwave pre-treatments acidic condition was preferable to increase the shorter aerobic biodegradability; the alkaline condition was favourable to intensify the anaerobic digestion process.