bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptive platform trials using multi-arm, multi-stage protocols: getting fast answers in pandemic settings
Authors: Noor Nurulamin M. , Pett Sarah L. , Esmail Hanif , Crook Angela M. , Vale Claire L. , Sydes Matthew R. , Parmar Mahesh K.B.
Published: November 2020

Global health pandemics, such as coronavirus disease 2019 (COVID-19), require efficient and well-conducted trials to determine effective interventions, such as treatments and vaccinations. Early work focused on rapid sequencing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), subsequent in-vitro and in-silico work, along with greater understanding of the different clinical phases of the infection, have helped identify a catalogue of potential therapeutic agents requiring assessment.

In a pandemic, there is a need to quickly identify efficacious treatments, and reject those that are non-beneficial or even harmful, using randomised clinical trials. Whilst each potential treatment could be investigated across multiple, separate, competing two-arm trials, this is a very inefficient process. Despite the very large numbers of interventional trials for COVID-19, the vast majority have not used efficient trial designs.

Well conducted, adaptive platform trials utilising a multi-arm multi-stage (MAMS) approach provide a solution to overcome limitations of traditional designs. The multi-arm element allows multiple different treatments to be investigated simultaneously against a shared, standard-of-care control arm. The multi-stage element uses interim analyses to assess accumulating data from the trial and ensure that only treatments showing promise continue to recruitment during the next stage of the trial.

The ability to test many treatments at once and drop insufficiently active interventions significantly speeds up the rate at which answers can be achieved. This article provides an overview of the benefits of MAMS designs and successes of trials, which have used this approach to COVID-19. We also discuss international collaboration between trial teams, including prospective agreement to synthesise trial results, and identify the most effective interventions. We believe that international collaboration will help provide faster answers for patients, clinicians, and health care systems around the world, including for each further wave of COVID-19, and enable preparedness for future global health pandemics.
Narcolepsy in Parkinson's disease with insulin resistance
Authors: Chunduri Alisha , Crusio Wim E. , Delprato Anna
Published: November 2020

Background: Parkinson’s disease (PD) is characterized by its progression of motor-related symptoms such as tremors, rigidity, slowness of movement, and difficulty with walking and balance. Comorbid conditions in PD individuals include insulin resistance (IR) and narcolepsy-like sleep patterns. The intersecting sleep symptoms of both conditions include excessive daytime sleepiness, hallucinations, insomnia, and falling into REM sleep more quickly than an average person. Understanding of the biological basis and relationship of these comorbid disorders with PD may help with early detection and intervention strategies to improve quality of life.

Methods: In this study, an integrative genomics and systems biology approach was used to analyze gene expression patterns associated with PD, IR, and narcolepsy in order to identify genes and pathways that may shed light on how these disorders are interrelated. A correlation analysis with known genes associated with these disorders (LRRK2, HLA-DQB1, and HCRT) was used to query microarray data corresponding to brain regions known to be involved in PD and narcolepsy. This includes the hypothalamus, dorsal thalamus, pons, and subcoeruleus nucleus. Risk factor genes for PD, IR, and narcolepsy were also incorporated into the analysis.

Results: The PD and narcolepsy signaling networks are connected through insulin and immune system pathways. Important genes and pathways that link PD, narcolepsy, and IR are CACNA1C, CAMK1D, BHLHE41, HMGB1, and AGE-RAGE.

Conclusions: We have identified the genetic signatures that link PD with its comorbid disorders, narcolepsy and insulin resistance, from the convergence and intersection of dopaminergic, insulin, and immune system related signaling pathways. These findings may aid in the design of early intervention strategies and treatment regimes for non-motor symptoms in PD patients as well as individuals with diabetes and narcolepsy.
The Role of Online Services in the Implementation of the Educational Network Project on Biology «Gallery of Hormones»
Authors: Gerasimova E. , Zenkina S.
Published: November 2020

The article shows the experience of using online services in the organization of a training network project in biology on a specific example. Online services act as an accessible tool for creating e-learning materials, which are embedded in an interactive project guide for the purpose of organizing project research activities of students.
Tłumaczenie prawa unijnego a centralne pojęcia przekładoznawstwa
Authors: Biel Łucja
Published: November 2020

Translation of EU law versus the central concepts of Translation Studies The objective of the paper was: (1) to analyse EU translation in light of central concepts of Translation Studies, and (2) to attempt a synthesis of numerous studies on EU translation to describe its distinctive features. EU law is adopted in 24 official languages and is applied in 28 Member States. The translation of EU law has an authoritative status. Owing to a complex array of political, procedural, legal and institutional factors, the translation of EU law poses a challenge to central TS concepts, such as a source text and a target text (versus language versions), a translation process (translation as part of a multistage and multilingual drafting
Translation of Questionnaires in Cross-National Social Surveys: A Niche with its Own Theoretical Framework and Methodology
Authors: Przepiórkowska Danuta
Published: November 2020

Translation of Questionnaires in Cross-National Social Surveys: A Niche with its Own Theoretical Framework and Methodology The paper describes the niche of questionnaire translation in cross-national surveys and its characteristics (theoretical framework and scholarly reflection, methodology, practice of questionnaire translation), indicating some gaps to be filled by future Translation Studies research in this subfield.
Na(d)pisy teatralne – translacja pomiędzy sztuką a techniką
Authors: Czubińska Małgorzata
Published: November 2020

Surtitles – translation between art and technology Surtitling, one of the multiple modern forms of stage translation, consists in the projection on a screen above the stage the text necessary for the understanding of the original drama. It is also a kind of hybrid form of translation situated between interpretation and translation and between audiovisual and literary translation. Based on the theatre semiotics, the author of this paper will determine the difference between surtitling and other forms of audiovisual translation and traditional theatre translation. The main purpose is to define phases of the work on the French version of surtitles for „(A)pollonia” – Polish drama directed by Krzysztof Warlikowski. As theatre art is always based on collaboration, we will determine and describe the contributions of the translator, director and surtitler to the final result – a play with surtitles.
Analyzing the Performance and Application of CERES-Wheat and APSIM in the Guanzhong Plain, China
Authors: Saddique Qaisar , Zou Yufeng , Ajaz Ali , Ji Jianmei , Xu Jiatun , Azmat Muhammad , Rahman Muhammad Habib ur , He Jianqiang , Cai Huanjie
Published: November 2020

Highlights

APSIM and CERES-Wheat were calibrated and evaluated for winter wheat in the Guanzhong Plain, China.

Both models performed well as the result of the calibration based on comprehensive field data.

CERES-Wheat showed high sensitivity to field capacity.

APSIM showed high sensitivity to nitrate at sowing.

A crop model ensemble is better than a single model application, particularly for grain yield.

Abstract. Cropping system models are useful tools to estimate the impact of climate and environment on agricultural production and to improve the management of agricultural systems. Numerous crop models are used worldwide to simulate wheat crop growth and predict yield. In this study, two process-based crop models (APSIM and CERES-Wheat) were assessed for simulating wheat crop growth in the Guanzhong Plain, China. The main objectives were to compare the performance of both models and perform sensitivity analysis. The possibility of reducing the model output uncertainty by estimating ensemble means was also explored. Crop models were calibrated and evaluated using local experimental data from three growing seasons (2009 to 2012), which encompassed 27 crop managements based on different levels of irrigation and nitrogen application. APSIM and CERES-Wheat performed well after calibration. The nRMSE for aboveground biomass, grain yield, LAI, canopy nitrogen, cumulative evapotranspiration, water use efficiency, and nitrogen fertilizer productivity was less than 21%. Sensitivity analysis of both models showed that grain yield in CERES-Wheat was more sensitive to field capacity. In APSIM, grain yield was sensitive to nitrogen application rate. Mean ensemble model results showed reduced uncertainty for simulated crop parameters, especially for differences between observed and simulated grain yield, which were reduced by up to 4.1%. Overall, the results suggest that APSIM and CERES-Wheat are both suitable for simulating wheat crop growth, development, and yield in the Guanzhong Plain. Furthermore, by using the ensemble modeling approach, decision-makers can be more confident in their planning, as the information will be based on multiple models’ results. Keywords: Crop model ensemble, Model calibration, Multiple crop models, Sensitivity analysis, Winter wheat.
Comparison of Object Detection Methods for Corn Damage Assessment Using Deep Learning
Authors: Hamidisepehr Ali , Mirnezami Seyed V. , Ward Jason K.
Published: November 2020

Highlights

Corn damage detection was possible using advanced deep learning and computer vision techniques trained with images of simulated corn lodging.

RetinaNet and YOLOv2 both worked well at identifying regions of lodged corn.

Automating crop damage identification could provide useful information to producers and other stakeholders from visual-band UAS imagery.

Abstract. Severe weather events can cause large financial losses to farmers. Detailed information on the location and severity of damage will assist farmers, insurance companies, and disaster response agencies in making wise post-damage decisions. The goal of this study was a proof-of-concept to detect areas of damaged corn from aerial imagery using computer vision and deep learning techniques. A specific objective was to compare existing object detection algorithms to determine which is best suited for corn damage detection. Simulated corn lodging was used to create a training and analysis data set. An unmanned aerial system equipped with an RGB camera was used for image acquisition. Three popular object detectors (Faster R-CNN, YOLOv2, and RetinaNet) were assessed for their ability to detect damaged areas. Average precision (AP) was used to compare object detectors. RetinaNet and YOLOv2 demonstrated robust capability for corn damage identification, with AP ranging from 98.43% to 73.24% and from 97.0% to 55.99%, respectively, across all conditions. Faster R-CNN did not perform as well as the other two models, with AP between 77.29% and 14.47% for all conditions. Detecting corn damage at later growth stages was more difficult for all three object detectors. Keywords: Computer vision, Faster R-CNN, RetinaNet, Severe weather, Smart farming, YOLO.
A Nanomaterial-Based Biosensor for the Quantitative Detection of Enrofloxacin Residues in Raw Chicken
Authors: Shen Yafang , He Yawen , Fu Yingchun , Wang Jianping , Zhang Jianmin , Liao Ming , Li Yanbin
Published: November 2020

Highlights

A nanobiosensor was developed for rapid detection of enrofloxacin residues in chicken meat.

5-Sulfosalicylic acid was adopted in a facile method for pretreatment of chicken meat samples.

The detection limit of 14.1 µg kg-1 was below the maximum residue limit for chicken meat.

The total detection time from sample pretreatment to result report was less than 1.5 h.

Abstract. Antibiotic residues in animal-derived food products have been identified as a potential hazard in human health. Hence, a rapid, simple, and cost-effective method for detection of antibiotics in the food supply chain is highly desirable. The objective of this study was to develop a nanomaterial-based biosensor using immunomagnetic beads (IMBs) and quantum dots (QDs) for rapid and sensitive detection of enrofloxacin (ENR) residues in raw chicken. A 5-sulfosalicylic acid-based pretreatment method was adopted to extract ENR from chicken meat and reduce non-specific adsorption caused by complex food matrices. Two sensing elements were designed and fabricated: antibody functionalized IMBs and ENR-bovine serum albumin (BSA) conjugates modified QDs (QDs-BSA-ENR). Target ENR in samples was first captured and separated by IMBs, and then QDs-BSA-ENR, serving as a competitor and detection probe, was used to react with the residual binding sites on the IMB surfaces. With the presence of captured ENR, the binding of QDs-BSA-ENR to IMBs was competitively inhibited. Finally, the fluorescence intensity of reporting QDs in the QDs-BSA-ENR-IMBs complex at a wavelength of 614 nm was measured for the quantitation of target antibiotics. Under the optimum conditions, the proposed method allowed sensitive detection of ENR in a linear range from 1 to 100 ng mL-1 with a limit of detection (LOD) of 0.94 ng mL-1. The LOD for spiked chicken meat was 14.1 µg kg-1, which was below the maximum residue limits (MRLs) regulated in China and the European Union. The whole analytical procedure from food sampling to result report could be finished in less than 1.5 h. This nanobiosensor showed high potential for rapid and low-cost detection of ENR residues in the poultry supply chain to enhance food safety. Keywords: Enrofloxacin, Immunomagnetic beads, Nanobiosensor, Poultry, Quantum dots, Rapid detection.
Effects of Elevated Platform and Robotic Vehicle on Broiler Production, Welfare, and Housing Environment
Authors: Yang Xiao , Huo Xiaojing , Li Guoming , Purswell Joseph L. , Tabler George T. , Chesser Gary D. , Magee Christopher L. , Zhao Yang
Published: November 2020

Highlights

Using an elevated platform with a manure catcher reduced litter moisture content and ammonia concentration.

A robotic vehicle encouraged bird movement and use of the elevated platform.

Using the elevated platform and robotic vehicle jointly improved broiler paw quality and plumage cleanliness.

Abstract. Elevated platform (EP) and robotic vehicle (RV) are two emerging systems aiming to improve environment enrichment and bird activity in broiler housing systems. However, the impacts of these systems on broiler production, welfare, and housing environment have not been evaluated. The objective of this study was to evaluate the effects of using EP and RV individually or jointly on broiler feed conversion ratio (FCR), litter moisture content (LMC), ammonia (NH3) concentration, gait score (GS), paw quality (PQ), plumage cleanliness (PC), and bird activity index (AI). Broilers were reared for eight-week production cycles. Four experimental rooms (54 birds room-1) were randomly assigned four treatments: EP only, RV only, EP and RV (EP+RV), and neither EP nor RV (Ctrl). Broiler GS, PQ, and PC were assessed following welfare protocols. Bird AI was determined through image processing. The experiment was repeated three times. The results showed that overall FCR values were 1.806 for EP, 1.804 for RV, 1.797 for EP+RV, and 1.791 for Ctrl. The normalized LMC values were 23.2% ±4.1% for EP, 32.8% ±4.1% for RV, 23.4% ±2.5% for EP+RV, and 35.7% ±7.0% for Ctrl over the eight-week production cycles. NH3 concentrations were 40% lower in the rooms with EP than in the rooms without EP at the end of the production cycle. Broilers had better PQ in the rooms with EP than in the rooms without EP. Broiler PC seemed better in the rooms with RV compared to those without RV. Operation of RV increased bird AI; however, the benefits in activity encouragement diminished as the broilers grew. The number of broilers on the EP was higher in the EP+RV rooms than in the EP rooms. It is concluded that using EP and RV together may improve broiler welfare and activity without compromising their production performance. Keywords: Behavior, Broiler, Elevated platform, Robotic vehicle, Welfare.
A Time and Motion Study for Evaluation of Apple Harvest Processes with Different Harvest Methods
Authors: Zhang Zhao , Lu Renfu , Igathinathane Cannayen
Published: November 2020

Highlights

Workers’ apple harvest processes with three harvest methods were evaluated and compared.

All three harvest methods had low overall harvest efficiency.

Harvest efficiency for the ladder-and-bucket method can be improved by reducing non-picking activities.

Innovation for harvest platform systems should focus on improving fruit picking activities.

Abstract. In recent years, harvest platforms are being increasingly used by apple growers in the U.S. and many other countries to replace the traditional ladder-and-bucket harvest method. However, the current harvest platforms still have low levels of automation, which limits their potential to achieve greater productivity improvement. This study was therefore aimed at analyzing the harvest process by fruit pickers with three distinct harvest methods and determining potential areas for efficiency improvement. Video recordings of workers with the traditional ladder-and-bucket method, DBR vacuum harvester, and Huron Fruit Systems harvest platform were collected at three commercial orchards during the 2018 harvest season. The videos were then analyzed, using the time and motion technique, and categorized into picking and non-picking activities. Results showed that the average picking time by workers for the ladder-and-bucket, DBR, and Huron harvest methods were 64%, 78%, and 83% of the total time, respectively. After further dividing the picking activity into approaching, detaching, and transporting actions, it was found that the detaching action, which is essential in fruit picking, accounted for only 30% to 32% of the total picking time for the three methods, with the remaining 2/3 of the time spent on the approaching and transporting actions. The ladder-and-bucket, DBR, and Huron harvest methods had a low overall apple detaching efficiency of 21%, 23%, and 26%, respectively, and an overall time index of 45%, 71%, and 80%, respectively (these two parameters were introduced for measuring harvest efficiency). Hence, significant opportunities exist for improving harvest efficiency for the three methods. For the ladder-and-bucket method, efforts should be made on improving non-picking activities, i.e., fruit unloading and minimizing the walking distance to the fruit unloading station or bin. For harvest platforms, efforts should be devoted to the development of innovative fruit catching or receiving and bin filling technologies to reduce fruit picking time (i.e., reducing the time needed to reach fruit on trees and transport picked fruit to conveyors) as well as alleviate the physical demand and occupational hazard for workers by eliminating the use of buckets. Keywords: Apple, Fruit picking, Harvest efficiency, Harvest platform, Horticulture crops, Vacuum harvest.
Quasi-Isotropic Initial Triangulation of NURBS Surfaces
Authors: Adan Daniel Herrero , Cardoso Rui
Published: November 2020

Isotropic triangulation of NURBS surfaces provides high quality triangular meshes, where all triangles are equilateral. This isotropy increases representation quality and analysis accuracy. We introduce a new algorithm to generate quasi-isotropic triangulation on NURBS surfaces at once, with no prior meshing. The procedure consists of one front made of vertexes that advances in a divergence manner avoiding front collision. Vertexes are calculated by arcs intersection whose radius length is estimated by trapezoidal rule integration of directional derivatives. The parameter space is discretized in partitions such that the error of trapezoidal rule is controlled. A new space, called pattern space, is used to infer the direction of the arcs intersection. Derivatives, whose analytical computation is expensive, are estimated by NURBS surface fitting procedures, which raise the speed of the process. The resultant algorithm is robust and efficient. The mesh achieved possesses most of the triangles equilateral and with high uniformity of sizes. The performance is illustrated by measuring angles, vertex valences and size uniformity in numerical examples
Subsampled digital holographic image reconstruction by a compressive sensing approach
Authors: de Souza J. C. , Freire R. B. R. , dos Santos P. A. M.
Published: November 2020

We show an in-line digital holographic image reconstruction from subsampled holograms with resolution improvement and lensless magnification with high noise immunity by a compressive sensing approach. Our method treats the sensed field as subsampled, low-pass filtered and projected on a Fresnel–Bluestein base in an inverse problem approach to image reconstruction with controlled lensless magnification. So, we have demonstrated by simulation and experimental results that the approach can reconstruct images with quality even when used in holograms obtained from unusual subsampling schemes.
Characterization of an angular domain fluorescence optical projection tomography system for mesoscopic lymph node imaging
Authors: Torres Veronica C. , Li Chengyue , Zhou Wei , Brankov Jovan G. , Tichauer Kenneth M.
Published: November 2020

Transmittance and fluorescence optical projection tomography can offer high-resolution and high-contrast visualization of whole biological specimens; however, applications are limited to samples exhibiting minimal light scattering. Our previous work demonstrated that angular-domain techniques permitted imaging of

∼

1

c
m

diameter noncleared lymph nodes because of their low scattering nature. Here, an angle-restricted transmittance/fluorescence system is presented and characterized in terms of geometric and fluorescence concentration reconstruction accuracy as well as spatial resolution, depth of focus, and fluorescence limits of detection. Using lymph node mimicking phantoms, results demonstrated promising detection and localization capabilities relevant for clinical lymph node applications.
Reconfigurable nonreciprocity with low insertion loss using a simple two-level system
Authors: Hu Yiqi , Zhang Shicheng , Kuang Xinyi , Qi Yihong , Lin Gongwei , Gong Shangqing , Niu Yueping
Published: November 2020

Nonreciprocal light propagation is essential to control the direction of the light flow. Here, we report the realization of magnetic-free optical nonreciprocity using a simple two-level system driven by a pump field in warm atoms. In our experiment, we not only demonstrate less than 0.5 dB of insertion loss and up to 20 dB of isolation but also provide flexible and reconfigurable operations of the isolation bandwidth, frequency, and direction. Nonreciprocal scheme with these characteristics may find important applications in photonic devices.
Nonreciprocal Fabry-Perot effect and performance enhancement in a magneto-optical InSb-based Faraday terahertz isolator
Authors: Keshock Elise , Peng Peisong , Zhou Jiangfeng , Talbayev Diyar
Published: November 2020

The Faraday effect due to the cyclotron resonance of conduction electrons in semiconductor InSb allows for nonreciprocity of transmitted light in our Faraday THz isolator operating in the presence of a small magnetic field. We select InSb as an efficient medium for our isolator due to its high electron mobility, low electron effective mass, and narrow band gap. Experimental measurements of the isolator performance indicate a maximum achieved isolation power of 18.8 dB with an insertion loss of −12.6 dB. Our optical analysis of the device points to a remarkable nonreciprocal Fabry-Perot effect in the magneto-optical InSb layer as the origin of the multi-fold isolation enhancement. This nonreciprocity occurs as the Fabry-Perot reflections in the forward direction add constructively and enhance the transmittance at certain frequencies, while the Fabry-Perot reflections in the backward direction add destructively and suppress the transmittance at the same frequencies.
Conditional generative adversarial network demosaicing strategy for division of focal plane polarimeters
Authors: Sargent Garrett C. , Ratliff Bradley M. , Asari Vijayan K.
Published: November 2020

Division of focal plane (DoFP), or integrated microgrid polarimeters, typically consist of a 2 × 2 mosaic of linear polarization filters overlaid upon a focal plane array sensor and obtain temporally synchronized polarized intensity measurements across a scene, similar in concept to a Bayer color filter array camera. However, the resulting estimated polarimetric images suffer a loss in resolution and can be plagued by aliasing due to the spatially-modulated microgrid measurement strategy. Demosaicing strategies have been proposed that attempt to minimize these effects, but result in some level of residual artifacts. In this work we propose a conditional generative adversarial network (cGAN) approach to the microgrid demosaicing problem. We evaluate the performance of our approach against full-resolution division-of-time polarimeter data as well as compare against both traditional and recent microgrid demosaicing methods. We apply these demosaicing strategies to data from both real and simulated visible microgrid imagery and provide an objective criteria for evaluating their performance. We demonstrate that the proposed cGAN approach results in estimated Stokes imagery that is comparable to full-resolution ground truth imagery from both a quantitative and qualitative perspective.
Anomalous motion of a particle levitated by Laguerre–Gaussian beams
Authors: Li Yang , Zhou Lei-Ming , Zhao Nan
Published: November 2020

Laguerre–Gaussian (LG) beams have orbital angular momentum (OAM). A particle trapped in an LG beam will rotate about the beam axis, due to the transfer of OAM. The rotation of the particle is usually in the same direction as that of the beam OAM. However, we discovered that when the LG beam is strongly focused, the rotation of the particle and the beam OAM might be in the opposite direction. This anomalous effect is caused by the negative torque on the particle exerted by the focused LG beam, which is similar to the optical pulling force in the linear case. We calculated the optical radiation force distribution of a micro-particle trapped in optical tweezers formed by a strongly focused LG beam, and showed that there exist stable trajectories of the particle that are controlled by the negative torque. We propose several necessary conditions for observing the counter-intuitive trajectories. Our work reveals that the strongly trapped micro-particle exhibits diversity of motion patterns.
Fourth-harmonic generation of orbital angular momentum light with cascaded quasi-phase matching crystals
Authors: Ge Zheng , Zhou Zhi-Yuan , Li Yan , Yang Chen , Liu Shi-Kai , Shi Bao-Sen
Published: November 2020

Orbital angular momentum (OAM) light, combined with the nonlinear process to expand the frequency range, has drawn increasing research interest in recent years. Here, we implement the first, to the best of our knowledge, experimental fourth-harmonic generation of OAM light with two cascaded quasi-phase-matching crystals. A Laguerre–Gaussian beam was transmitted through a duplet crystals system and frequency-doubled twice by two separate second-harmonic generation processes, which transduced the frequency of the OAM beam from telecom band to visible band and then to ultraviolet (UV) band. The topological charge of the OAM beam was increased substantially in the cascaded frequency conversion processes. In this experiment, we verify the OAM conservation by utilizing a specially designed interferometer, and the results correspond well with the numerical simulation. This work provides an effective method for the generation of UV OAM beams with high topological charges.
Microfluidic tuning of linear and nonlinear absorption in graphene oxide liquid crystals
Authors: Rezaei Mirghaed M. , Arshadi Pirlar M. , Jahanbakhshian M. M. , Karimzadeh R.
Published: November 2020

Manipulation of the nonlinear optical response of materials plays a significant role in photonics applications; however, it may be irreversible, untunable, and uncontrollable, which makes it difficult. In this Letter, we present a mechanical-hydrodynamical approach through a microchannel to tune the nonlinear absorption response of graphene oxide liquid crystals. In this material, the optical properties depend on the flake orientation. This feature has helped us to study empirically the dependency of the nonlinear absorption coefficients to external hydrodynamical force by employing the Z-scan technique. The experimental results show that increasing the flow rate in the microchannel enhances both linear and nonlinear absorption coefficients and, as a result, reduces the laser beam transmission through the sample. It has been observed that the percentage change in the nonlinear absorption coefficient of the sample is significant due to the flow rate.
Nonlinear accelerated orbiting motions of optical trapped particles through two-photon absorption
Authors: Zhang Xiaohe , Rui Guanghao , He Jun , Cui Yiping , Gu Bing
Published: November 2020

Vortex beams carrying optical angular momentum (AM) could drive the orbital motion of a small particle around the optical axis. In general, the orbital rotation speed of trapped particles increases linearly with the increasing laser power. Beyond the linear optics regime, in this work, we investigate both the optical force and torque on a two-photon absorbing Rayleigh particle produced by the tightly focused femtosecond-pulsed circularly polarized vortex beam. Different from the trapping dynamics of particles without two-photon absorption (TPA), it is shown that the orbital motion of trapped particles with TPA accelerates nonlinearly as the laser power increases. Moreover, the orbital motion acceleration of trapped particles is proportional to the TPA coefficient. The corresponding underlying mechanism is discussed in detail. Our results may find interesting applications in the characterization of the optical nonlinearity of a single nanoparticle, and AM manipulation and particle transportation in the nonlinear optics regime.
Focused Gaussian beam in the paraxial approximation
Authors: Das Ankur , Soltani Navid , Agio Mario
Published: November 2020

A focused Gaussian beam represents a case of highly practical importance in many areas of optics and photonics. We derive analytical expressions for a focused Gaussian beam in the paraxial approximation, considering an arbitrary lens filling factor. We discuss the role of higher-order Bessel functions of the first kind in defining the electric field in the focal region.
Fabrication of highly efficient pure blue-emitting electroluminescent
devices using ZnSe/ZnSexS1-x/ZnS QDs
Authors: Jung Woon Ho , Yoo Jeong-Yeol , Kim Hyun jun , Kim Jong-Gyu , Chin Byung Doo , Kim Jang Sub
Published: November 2020

Since electroluminescent (EL) quantum dots (QDs) are considered a key
component of the next-generation display, and large-scale production
of environment-friendly QDs is required for their wide use in
commercial displays. Therefore, several studies on non-cadmium QDs,
such as indium phosphide (InP) QDs in the III-V category, graphene
QDs, and copper indium sulfide (CuInS2) or silver indium
sulfide (AgInS2) QDs in the I-III-VI2 category,
have been conducted owing to their non-toxicity and good optical
properties. Subsequently, significant results have been reported for
green and red colors. However, for synthesis of blue QDs, pure blue
emission in the range of 440-460 nm has been achieved with few
materials. Among them, zinc selenide (ZnSe) is a promising candidate
for synthesizing blue QDs. However, owing to the wide band gap
(2.7 eV) of ZnSe, highly effective QDs were attained in the
violet region (420-440 nm). Here, for the first time, we have
synthesized ZnSe/ZnSexS1-x/ZnS QDs emitting at a
wavelength of 444 nm with high photoluminescence quantum yield
(PLQY) of 77.2%. Also, full width at half maximum (FWHM) of
23.3 nm ensured its excellent color purity. Use of a gradient
intermediate shell of ZnSeS in the original ZnSe/ZnS QDs was the key
factor behind this achievement. The intermediate gradient shell of
ZnSeS around the core delocalizes the electrons, weakening the quantum
confinement effect (QCE), hence rendering the emission color of the
QDs tunable from violet to blue by manipulating the ratio of selenium
(Se) and sulfur (S) in the composites. A blue emission peak centered
at 452 nm was observed for the quantum dot light-emitting
diodes (QD-LEDs) fabricated using the above-mentioned QDs, and an
external quantum efficiency (EQE) of 5.32%, current efficiency
of 1.51 cd/A, and power efficiency of 0.74 lm/W were reported.
Furthermore, our fabricated device exhibited a maximum brightness of
3,754 cd/m2 and a half operational time (LT50)
with 100 cd/m2 initial luminance of 1.27 h, which
are the highest values of these parameters to be reported till date
for a blue QD-LED fabricated using ZnSe core based QDs in pure blue
region.
Quantum correlations in electron microscopy
Authors: Mechel Chen , Kurman Yaniv , Karnieli Aviv , Rivera Nicholas , Arie Ady , Kaminer Ido
Published: November 2020

Electron microscopes provide a powerful platform for exploring physical phenomena with nanoscale resolution, based on the interaction of free electrons with the excitations of a sample such as phonons, excitons, bulk plasmons, and surface plasmons. The interaction usually results in the absorption or emission of such excitations, which can be detected directly through cathodoluminescence or indirectly through electron energy loss spectroscopy (EELS). However, as we show here, the underlying interaction of a free electron and an arbitrary optical excitation goes beyond what was predicted or measured so far, due to the interplay of entanglement and decoherence of the electron-excitation system. The entanglement of electrons and optical excitations can provide new analytical tools in electron microscopy. For example, it can enable measurements of optical coherence, plasmonic lifetimes, and electronic length scales in matter (such as the Bohr radius of an exciton). We show how these can be achieved using common configurations in electron diffraction and EELS, revealing significant changes in the electron’s coherence, as well as in other quantum information theoretic measures such as purity. Specifically, we find that the purity after interaction with nanoparticles can only take discrete values, versus a continuum of values for interactions with surface plasmons. We quantify the post-interaction density matrix of the combined electron-excitation system by developing a framework based on macroscopic quantum electrodynamics. The framework enables a quantitative account of decoherence due to excitations in any general polarizable material (optical environment). This framework is thus applicable beyond electron microscopy. Particularly in electron microscopy, our work enriches analytical capabilities and informs the design of quantum information experiments with free electrons, allowing control over their quantum states and their decoherence by the optical environment.
Circumventing the optical diffraction limit with customized speckles
Authors: Bender Nicholas , Sun Mengyuan , Yılmaz Hasan , Bewersdorf Joerg , Cao Hui
Published: November 2020

Speckle patterns have been used widely in imaging techniques such as ghost imaging, dynamic speckle illumination microscopy, structured illumination microscopy, and photoacoustic fluctuation imaging. Recent advances in the ability to control the statistical properties of speckles has enabled the customization of speckle patterns for specific imaging applications. In this work, we design and create special speckle patterns for parallelized nonlinear pattern-illumination microscopy based on fluorescence photoswitching. We present a proof-of-principle experimental demonstration where we obtain a spatial resolution three times higher than the diffraction limit of the illumination optics in our setup. Furthermore, we show that tailored speckles vastly outperform standard speckles. Our work establishes that customized speckles are a potent tool in parallelized super-resolution microscopy.
Topological photonics and beyond: introduction
Authors: Alù Andrea , Pilozzi Laura , Xu Haitan , Fan Jingyun
Published: November 2020

Topological photonics has been opening exciting opportunities in recent optics research. In this feature issue, we present a collection of papers outlining state-of-the-art and application perspectives for this thriving field of research.
Modelling habitat suitability in Jordan for the cutaneous leishmaniasis vector (Phlebotomus papatasi) using multicriteria decision analysis
Authors: Takahashi Emi A. , Masoud Lina , Mukbel Rami , Guitian Javier , Stevens Kim B.
Published: November 2020

Cutaneous leishmaniasis (CL) is a zoonotic vector-borne neglected tropical disease transmitted by female Phlebotomine sand flies. It is distributed globally but a large proportion of cases (70–75%) are found in just ten countries. CL is endemic in Jordan yet there is a lack of robust entomological data and true reporting status is unknown. This study aimed to map habitat suitability of the main CL vector, Phlebotomus papatasi, in Jordan as a proxy for CL risk distribution to (i) identify areas potentially at risk of CL and (ii) estimate the human population at risk of CL. A literature review identified potential environmental determinants for P. papatasi occurrence including temperature, humidity, precipitation, vegetation, wind speed, presence of human households and presence of the fat sand rat. Each predictor variable was (a) mapped; (b) standardized to a common size, resolution and scale using fuzzy membership functions; (c) assigned a weight using the analytical hierarchy process (AHP); and (d) included within a multicriteria decision analysis (MCDA) model to produce monthly maps illustrating the predicted habitat suitability (between 0 and 1) for P. papatasi in Jordan. Suitability increased over the summer months and was generally highest in the north-western regions of the country and along the Jordan Valley, areas which largely coincided with highly populated parts of the country, including areas where Syrian refugee camps are located. Habitat suitability in Jordan for the main CL vector—P. papatasi—was heterogeneous over both space and time. Suitable areas for P. papatasi coincided with highly populated areas of Jordan which suggests that the targeted implementation of control and surveillance strategies in defined areas such as those with very high CL vector suitability (>0.9 suitability) would focus only on 3.42% of the country’s total geographic area, whilst still including a substantial proportion of the population at risk: estimates range from 72% (European Commission’s Global Human Settlement population grid) to 89% (Gridded Population of the World) depending on the human population density data used. Therefore, high impact public health interventions could be achieved within a reduced spatial target, thus maximizing the efficient use of resources.
Two-step multi-omics modelling of drug sensitivity in cancer cell lines to identify driving mechanisms
Authors: Kusch Nina , Schuppert Andreas
Published: November 2020

Drug sensitivity prediction models for human cancer cell lines constitute important tools in identifying potential computational biomarkers for responsiveness in a pre-clinical setting. Integrating information derived from a range of heterogeneous data is crucial, but remains non-trivial, as differences in data structures may hinder fitting algorithms from assigning adequate weights to complementary information that is contained in distinct omics data. In order to counteract this effect that tends to lead to just one data type dominating supposedly multi-omics models, we developed a novel tool that enables users to train single-omics models separately in a first step and to integrate them into a multi-omics model in a second step. Extensive ablation studies are performed in order to facilitate an in-depth evaluation of the respective contributions of singular data types and of combinations thereof, effectively identifying redundancies and interdependencies between them. Moreover, the integration of the single-omics models is realized by a range of distinct classification algorithms, thus allowing for a performance comparison. Sets of molecular events and tissue types found to be related to significant shifts in drug sensitivity are returned to facilitate a comprehensive and straightforward analysis of potential computational biomarkers for drug responsiveness. Our two-step approach yields sets of actual multi-omics pan-cancer classification models that are highly predictive for a majority of drugs in the GDSC data base. In the context of targeted drugs with particular modes of action, its predictive performances compare favourably to those of classification models that incorporate multi-omics data in a simple one-step approach. Additionally, case studies demonstrate that it succeeds both in correctly identifying known key biomarkers for sensitivity towards specific drug compounds as well as in providing sets of potential candidates for additional computational biomarkers.
Experiences and views of people with diabetes during Ramadan fasting: A qualitative meta-synthesis
Authors: Liao Jieying , Wang Tianfang , Li Zhan , Xie Haotian , Wang Shanshan
Published: November 2020

Objectives

To review and appraise the existing qualitative studies on Ramadan fasting in participants with diabetes and to integrate valuable qualitative evidence for optimizing diabetes management.

Methods

Twelve databases (PubMed, Embase, Cochrane Library, Science Direct, CINAHL, PsycINFO, JBI (Joanna Briggs institute), Web of Science, and four Chinese databases) were searched to identify qualitative studies on experiences and perspectives of Ramadan fasting in participants with diabetes. CASP (Critical Appraisal Skills Program) Qualitative Checklists were applied to appraise the included studies. A meta-synthesis approach was used to analyze the included studies. Through the strategy of inductive thematic synthesis and reciprocal interpretation, the findings and quotations of the included studies were integrated into new themes and categories. The CERQual (Confidence in the Evidence from Reviews of Qualitative Research) tool was used to grade the confidence of the new themes.

Results

A total of 11 qualitative studies were included, and 43 findings were isolated. Ten new themes were identified and synthesized from the findings. Finally, four new categories were integrated, including the knowledge and understanding of observing Ramadan fasting, well-being and challenges, self-efficacy, and needs and expectations of participants with diabetes during Ramadan.

Conclusions

Insulin-dependent individuals call for special concern during Ramadan fasting. Ramadan-focused education needs to be developed and generalized, and existing guidelines should be improved to optimize the management of diabetes. Professional HCPs contribute to weigh the health risks and mental satisfaction for their patients, partly, to balance health and religion. Participants’ psychological construction is another concern for religious scholars and psychologists.
Increasing secular trends in height and obesity in children with type 1 diabetes: JSGIT cohort
Authors: Mochizuki Mie , Ito Yoshiya , Yokomichi Hiroshi , Kikuchi Toru , Soneda Shun , Musha Ikuma , Anzou Makoto , Kobayashi Koji , Matsuo Kumihiro , Sugihara Shigetaka , Sasaki Nozomu , Matsuura Nobuo , Amemiya Shin ,   On behalf of The Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes (JSGIT)
Published: November 2020

Background

Recently, anthropometric indices in children with type 1 diabetes mellitus (T1DM) have begun to change.

Objective

To examine secular trends in patients’ anthropometric indices.

Subjects

Japanese children with T1DM from the 1995, 2000, 2008 and 2013 cohorts of The Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes.

Methods

We analysed serum haemoglobin A1c (HbA1c) levels, the incidence of severe hypoglycaemic events, the types and doses of insulin, height standard deviation scores (SDS), body mass index (BMI) percentiles compared with healthy Japanese children and obesity prevalence over time. We also stratified the patients according to glycaemic control levels of <58 mmol/mol (optimal), 58–75 mmol/mol (suboptimal) and ≥75 mmol/mol (high-risk).

Results

Data for 513–978 patients from each of the cohorts were analysed. The incidence of severe hypoglycaemic events decreased over time (from 21 to 4.8/100 patient-years), while the proportion of insulin analogue doses increased (14.6% to 98.6%). In addition, patient height SDS (−0.22 to +0.17), BMI percentile (52.1 to 58.7) and obesity prevalence (2.1% to 5.1%) increased. Height SDS increased in all of the glycaemic control subgroups, while BMI percentile and obesity prevalence increased in the suboptimal and high-risk groups.

Conclusions

Since 1995, the average height of children with T1DM has increased in parallel with increasing insulin doses. Clinicians should be aware of increased BMI in these patients and the associated risk of developing cardiovascular disease in the future.
Baroreflex gain and time of pressure decay at different body temperatures in the tegu lizard, Salvator merianae
Authors: Filogonio Renato , Orsolini Karina F. , Oda Gustavo M. , Malte Hans , Leite Cléo A. C.
Published: November 2020

Ectotherms may experience large body temperature (Tb) variations. HigherTbhave been reported to increase baroreflex sensitivity in ectotherm tetrapods. At lowerTb, pulse interval (PI) increases and diastolic pressure decays for longer, possibly resulting in lower end-diastolic pressures and mean arterial pressures (Pm). Additionally, compensatory baroreflex-related heart rate modulation (i.e. the cardiac branch of the baroreflex response) is delayed due to increased PI. Thus, lowTbis potentially detrimental, leading to cardiovascular malfunctioning. This raises the question on howPmis regulated in such an adverse condition. We investigated the baroreflex compensations that enables tegu lizards,Salvator merianae, to maintain blood pressure homeostasis in a wideTbrange. Lizards had their femoral artery cannulated and pressure signals recorded at 15°C, 25°C and 35°C. We used the sequence method to analyse the heart rate baroreflex-related corrections to spontaneous pressure fluctuations at each temperature. Vascular adjustments (i.e. the peripheral branch) were assessed by calculating the time constant for arterial pressure decay (τ)—resultant from the action of both vascular resistance and compliance—by fitting the diastolic pressure descent to the two-elementWindkesselequation. We observed that at lowerTb, lizards increased baroreflex gain at the operating point (Gop) and τ, indicating that the diastolic pressure decays at a slower rate.Gopnormalized toPmand PI, as well as the ratio τ/PI, did not change, indicating that both baroreflex gain and rate of pressure decay are adjusted according to PI lengthening. Consequently, pressure parameters and the oscillatory power fraction (an index of wasted cardiac energy) were unaltered byTb, indicating that bothGopand τ modulation are crucial for cardiovascular homeostasis.