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This Special Issue is associated with the European Conference on Integrated Optics (ECIO), held on May 4–6, 2022, in Milan, Italy. This conference was the 23rd in a series that started in London in 1981. After the virtual edition of 2020 and the cancellation of the 2021 edition due to the COVID-19 pandemic emergency, the 2022 ECIO conference was hosted fully in presence by Politecnico di Milano and was attended by about 250 participants. The scientific sessions of the conference were opened by two plenary speakers, Prof. Volker Sorger of George Washington University, USA, and Prof. Paul Prucnal of Princeton University, USA, who presented recent developments on integrated photonics for machine learning, high-performance computing, and neural networks.
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In this chapter, the main techniques that use light to monitor and detect viruses and biomolecules will be presented, including Surface-Enhanced Raman Spectroscopy (SERS), Localized-Surface Plasmon Resonance (SPR), luminescence, and others. It will also be discussed the devices used to build biosensors and, in addition, the chemical modifications in waveguides to improve and innovate such technologies. Besides, it will also address how optical devices and materials are being explored in the detection and diagnosis of the new coronavirus, as some aspects related to the biological structure of SARS-CoV-2 and its detection. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023. All rights reserved.
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Sterilization of hospitals is one of the major concerns when it comes to hygiene and cleanliness especially during a pandemic situation. The existing methodologies include ultraviolet disinfection or hydrochloride spraying for sterilizing hospital rooms and chemical treatment for surgical and medical equipment. However since COVID strains are developing at a rapid rate, it is necessary for more efficacy and accuracy in sterilization. According to the August 2021 census collected by NCBI, 87 percent of virus transmission is only because of improper sterilization. The following paper proposes efficient and proven ultrasonic sterilization methods that can be preferred to ultraviolet and chemical sterilization in sterilizing not only hospital rooms but also any crowded regions like malls and schools. The Cremant's formula helps in determining the appropriate and effective sterilization ultrasonic frequency level. Using machine learning algorithms, the approximate location, and the number of droplets per second present in the room will be calculated and treated with ultrasonic waves. This demonstration is proved using micro silicon balls which are similar in properties of COVID - 19 viruses. Simulation results are displayed to show the working of the same.
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In recent years, spread of infection due to virus became whirlwind and creates threat to life in multiple ways. Hence there is in need to sense virus as early as possible in easier way. In this work we propose a multi virus sensor which senses IBV, H5N1, H9N2, and H4N6.Very low refractive index is sensed in this work with increased birefringence due to its elliptical core, where the samples are infiltrated. Numerical analysis is done using Finite Element Method. Among these 4 viruses, IBV has higher sensitivity, birefringence and lower confinement loss which belong to COVID family.88.56% of sensitivity is obtained at 1550nm with low confinement loss. © 2022 IEEE.
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The International School on Quantum Electronics "Laser Physics and Applications” was held for the first time as far back as 1980. Since then it has taken place biennially and has become an important international event in the field of laser physics and laser applications attracting participants from many countries, especially from south-eastern Europe. Traditionally, its program includes lectures delivered by prominent scientists dealing with investigations of basic physical phenomena, processes of interaction of laser radiation with matter and latest scientific results obtained in the research areas of quantum electronics and optics, as well as the technological practical applications of new ideas, devices, instruments and laser systems. Special attention is paid to the active participation of students and young scientists who have the opportunity to present their results and meet and share experience with outstanding professionals in their particular fields of research.The topics include the following:• Laser-matter interactions• Laser spectroscopy and metrology• Laser remote sensing and ecology• Lasers in biology and medicine• Laser systems and nonlinear optics• Alternative techniques for material synthesis and processingThe 22nd edition of the ICSQE was held as a virtual forum due to the restrictions related to COVID-19 pandemic from September 19th to 23rd, 2022. The Institute of Electronics, Bulgarian Academy of Sciences, located in Sofia, Bulgaria, hosted the conference organization. The Big Blue Button on-line system was used as a technical platform for the meeting. The technical sessions of the International School on Quantum Electronics included 22 invited talks (30 min + 5 min Q&A), a Mini-Symposium "Extreme light infrastructure”, 11 oral contributions (30 min + 5 min Q&A) and in total 51 poster presentations divided into 5 sessions (1 hour each). The platform was available 24 hours, allowing discussions in addition to the technical program. The total number of participants was 90 from 16 countries.The XXII International Conference and School on Quantum Electronics: "Laser Physics and Applications” was held by the financial support from the Bulgarian National Science Fund under Project No. KP-06-MNF/4, 20.07.2022.List of Committees, International Advisory Committee, Program Committee, Local Organizing Committee, Lecturers, Oral Presentations, Poster Presentations are available in this pdf.
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Microplasma UV lamps have recently emerged as viable excimer-based sources of UV radiation, garnering significant attention during the recent COVID-19 pandemic for their use in disinfection applications because of their ability to emit human-safe far-UVC (200-240 nm) spectrums. An accurate model to simulate the radiation profile of microplasma UV lamps is of paramount importance to develop efficient microplasma lamp-implemented systems. We developed a 3D numerical model of microplasma UV lamps using the ray optics method. The simulation results for lamp irradiance and fluence rate were experimentally validated with standard optical radiometry and actinometry measurements, respectively. To improve the optical efficiency of microplasma lamps, an in-depth analysis of radiation behavior inside the standard commercially available lamp was performed using the geometrical optics method, and several potential scenarios were explored. A 2D modeling of an individual microcavity indicated that the current common lamp design can be significantly improved by preventing radiation loss, and small modifications in optical design can greatly increase the energy performance of the system. Based on the findings of this study, several virtual design concepts were proposed, and their performances were numerically compared with that of the original design of commercial microplasma lamps. The developed model can potentially be integrated with hydrodynamic and kinetic models for the virtual prototyping of complex photoreactors operating with UV microplasma lamps.
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Artificially prepared microbial spores have excellent electromagnetic attenuation properties due to their special composition and structure. At present, studies on the optical properties of microbial spores have mainly focused on those with a single band or a single germplasm, which has limitations and cannot reveal the optical properties comprehensively. In this paper, 3 kinds of laboratory-prepared microbial spores were selected for compounding, and the spectral reflectivities of single-germplasm biospores and compound biospores were measured in the wavebands of 0.25–2.4 and 3–15 μm. The complex refractive indices (CRIs) were calculated in combination with the Kramers–Kronig (K-K) algorithm. Relying on the smoke box broadband test system, the transmittance of single-germplasm bioaerosols and compound bioaerosols from the ultraviolet (UV) band to the far-infrared (FIR) band was measured, and the mass extinction coefficients were calculated. The results indicate that the trend of the complex refractive indices of the compound spores is consistent with that of the single-germplasm spores with a larger particle size. For the single-germplasm bioaerosols, the lowest transmittance values were 2.21, 5.70 and 6.27% in the visible (VIS), near-infrared (NIR) and middle-infrared (FIR) bands, and the mass extinction coefficients reached 1.15, 0.87 and 0.84 m2/g, respectively. When AO and BB spores were compounded at 4:1, the extinction performance of the bioaerosols somewhat improved in all wavebands. These results can help to comprehensively analyze the optical properties of bioaerosols and provide ideas for the development of new extinction materials.
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Recently, during the COVID-19 pandemic, distance education became mainstream. Many students were not prepared for this situation—they lacked equipment or were not even connected to the Internet. Schools and government institutions had to react quickly to allow students to learn remotely. They had to provide students with equipment (e.g., computers, tablets, and goggles) but also provide them with access to the Internet and other necessary tools. On the other hand, teachers were trying to adopt new technologies in the teaching process to enable more interactivity, mitigate feelings of isolation and disconnection, and enhance student engagement. New technologies, including Virtual Reality (VR), Augmented Reality (AR), Mixed Reality (MR), Extended Reality (XR, so-called Metaverse), Big Data, Blockchain, and Free Space Optics (FSO) changed learning, teaching, and assessing. Despite that, some tools were implemented fast, and the COVID-19 pandemic was the trigger for this process;most of these technologies will be used further, even in classroom teaching in both schools and universities. This paper presents a concise review of the emerging technologies applied in distance education. The main emphasis was placed on their influence on the efficiency of the learning process and their psychological impact on users. It turned out that both students and teachers were satisfied with remote learning, while in the case of undergraduate children and high-school students, parents very often expressed their dissatisfaction. The limitation of the availability of remote learning is related to access to stable Internet and computer equipment, which turned out to be a rarity. In the current social context, the obtained results provided valuable insights into factors affecting the acceptance and emerging technologies applied in distance education. Finally, this paper suggests a research direction for the development of effective remote learning techniques. © 2023 by the authors.
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Sterilization of hospitals is one of the major concerns when it comes to hygiene and cleanliness especially during a pandemic situation. The existing methodologies include ultraviolet disinfection or hydrochloride spraying for sterilizing hospital rooms and chemical treatment for surgical and medical equipment. However since COVID strains are developing at a rapid rate, it is necessary for more efficacy and accuracy in sterilization. According to the August 2021 census collected by NCBI, 87 percent of virus transmission is only because of improper sterilization. The following paper proposes efficient and proven ultrasonic sterilization methods that can be preferred to ultraviolet and chemical sterilization in sterilizing not only hospital rooms but also any crowded regions like malls and schools. The Cremant's formula helps in determining the appropriate and effective sterilization ultrasonic frequency level. Using machine learning algorithms, the approximate location, and the number of droplets per second present in the room will be calculated and treated with ultrasonic waves. This demonstration is proved using micro silicon balls which are similar in properties of COVID - 19 viruses. Simulation results are displayed to show the working of the same. © 2022 IEEE.
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The CRyogenic InfraRed Echelle Spectrograph (CRIRES) Upgrade project CRIRES+ extended the capabilities of CRIRES. It transformed this VLT instrument into a cross-dispersed spectrograph to increase the wavelength range that is covered simultaneously by up to a factor of ten. In addition, a new detector focal plane array of three Hawaii 2RG detectors with a 5.3 μm cutoff wavelength replaced the existing detectors. Amongst many other improvements, a new spectropolarimetric unit was added and the calibration system has been enhanced. The instrument was installed at the VLT on Unit Telescope 3 at the beginning of 2020 and successfully commissioned and verified for science operations during 2021, partly remotely from Europe due to the COVID-19 pandemic. The instrument was subsequently offered to the community from October 2021 onwards. This article describes the performance and capabilities of the upgraded instrument and presents on sky results. © 2023 The Author(s).
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Swallowing disorders are frequently encountered pathologies. There are numerous etiologies which can be responsible. The consequences of dysphagia may lead to choking, aspiration pneumonia, denutrition, dehydration or even fatal issue. These disorders are more commonly found after prolonged intubation, as commonly seen in severe Covid-19 patients. Early screening and adequate diagnostic testing are necessary in order to prevent these different complications. It is thus important to define the underlying etiology and to assess the severity of dysphagia. This allows an adequate rehabilitation to maintain the patient on a sufficient oral diet adapted to his disorders.Copyright © 2022 Association des Medecins anciens etudiats de l'Universite libre de Bruxelles (A.M.U.B.). All rights reserved.
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Quantum computing was once regarded as a mere theoretical possibility, but recent advances in engineering and materials science have brought practical quantum computers closer to reality. Currently, representatives from industry, academia, and governments across the world are working to build the educational structures needed to produce the quantum workforce of the future. Less attention has been paid to growing quantum computing capacity at the high school level. This article details work at The University of Texas at Austin to develop and pilot the first full-year high school quantum computing class. Over the course of two years, researchers and practitioners involved with the project learned several pedagogical and practical lessons that can be helpful for quantum computing course design and implementation at the secondary level. In particular, we find that the use of classical optics provides a clear and accessible avenue for representing quantum states and gate operators and facilitates both learning and the transfer of knowledge to other Science, Technology, and Engineering (STEM) skills. Furthermore, students found that exploring quantum optical phenomena prior to the introduction of mathematical models helped in the understanding and mastery of the material.
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We propose and demonstrate an optical chaos secured optical body area network (OBAN) employing polarization multiplexing and free space optics links. The physiological data of patient coded in non-return to zero on-off keying (NRZ-OOK) format from two on-body nodes modulated on orthogonal polarization states of a continuous wave (CW) laser is secured by using additive chaos masking (ACM) technique with chaotic waveforms generated through direct modulation of semiconductor chaotic lasers (CLs). After polarization multiplexing, the secure NRZ- OOK modulated optical signals are transmitted over indoor and outdoor free space optics (FSO) links based on GammaGamma channel model towards remote healthcare center. After chaos subtraction, the NRZ-OOK modulated optical signals are photodetected and passed on to bit error rate (BER) estimator for performance analysis. The electronic health (e-health) system based on the proposed OBAN provides adequate privacy for classified patient related information with added advantages of acceptable BER results, cost efficiency, speedy installation and suitable for use in current pandemic situation. © 2022 IEEE.
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Red blood cells (RBCs) or erythrocytes are essential for oxygenating the peripherical tissue in the human body. Impairment of their physical properties may lead to severe diseases. Optical tweezers have in experiments been shown to be a powerful tool for assessing the biochemical and biophysical properties of RBCs. Despite this success there has been little theoretical work investigating of the stability of erythrocytes in optical tweezers. In this paper we report a numerical study of the trapping of RBCs in the healthy, native biconcave disk conformation in optical tweezers using the ray optics approximation. We study trapping using both single- and dual-beam optical tweezers and show that the complex biconcave shape of the RBC is a significant factor in determining the optical forces and torques on the cell, and ultimately the equilibrium configuration of the RBC within the trap. We also numerically demonstrate how the addition of a third or even fourth trapping laser beam can be used to control the cell orientation in the optical trap. The present investigation sheds light on the trapping mechanism of healthy erythrocytes and can be exploited by experimentalist to envisage new experiments.
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The detection of aerosols in general and bioaerosols more specific has gained an increased importance in multiple fields. While environmental scientists are increasingly interested in the impacts of aerosols onto climatic effects, researchers in the security sector are looking for ways to remotely detect dangerous substances from safe distances. Additionally, due to the corona pandemic, the detection of bioaerosols has gained significant relevance in sectors like public health, transportation, and aviation. As a result, more accurate, i.e. sensitive and specific, measurement equipment is needed. Here we present the design concept for a new sensor system designed to measure thin bioaerosol clouds. For the detection air samples are excited with laser light to generate a signal based on laser induced fluorescence. The fluorescence is collected in an integration sphere to optimize signal. Inside the integration sphere multiple sensors are placed, each combined with a filter to exclude all signals not belonging to a certain, agent specific wavelength interval. Through the intelligent combination of spectral intervals, a specific characteristic of the studied air sample is measured. Based on the measured characteristic a classification is performed to determine the category of the sample. Development aims at testing indoor air quality in real time. © 2022 SPIE.
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19–20 September 2022, Penang, MalaysiaThe Photonics Meeting is an annual event organized by the Optical Society of Malaysia (OSM) in celebrating UNESCO International Day of Light. For this year, the 5th Photonics Meeting 2022 (PM22) was held on 19th and 20th of September 2022 in collaboration with Universiti Sains Malaysia. PM22 with the theme "Exploring photonics breakthrough for humanity” has attracted 26 contributors that covers various topics on photonics including optical materials, laser physics, fiber optics and colorimetry. PM22 has been honoured with presentation from world renowned scientists from industry as well as international research laboratory and universities as the plenary and keynote speakers. PM22 would like to extend its great appreciation to all the committee members who have work diligently to ensure the smooth deliverance of this scientific event. Due to the Covid19 pandemic, the conference was fully conducted virtually through Cisco Webex platform hosted by School of Physics, Universiti Sains Malaysia. Each participant was given 10 minutes for their presentation and another 5 minutes for question and answer session. All submission has been thoroughly reviewed by the experts in the respective field and presented in this volume of Journal of Physics: Conference Series.List of Editors, Keynote Speaker, Plenary Speaker, Organizing Committee are available in this Pdf.
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The International Conference on Synchrotron Radiation Instrumentation (SRI) is a unique and significant international forum held every three years in the community of synchrotron radiation (SR) and free electron lasers (FEL). It is the prime forum for fostering connections between cutting-edge synchrotron radiation instrumentation, science, and the requirements of the user community. The SRI 2021 had originally been scheduled to take place in Hamburg in summer 2021. Due to the COVID-19 pandemic, it was postponed to 2022 and held as an online event.More than 1160 international participants from 25 countries met virtually at the SRI 2021. In nearly 290 talks and 450 posters, latest results were presented. Although it was an online-only conference, lively discussions took place in the nearly 40 parallel sessions, and the eight poster sessions were also very well attended.The main topics of the SRI conference were: new SR and FEL facilities, update plans of these facilities, and recent developments in various instrumentation areas like beamline design, X-ray optics, sample environments, detectors and spectrometers, data acquisition, and data analysis techniques or automation. These innovations contributed to new results for a wide range of experimental techniques and scientific applications such as X-ray scattering and spectroscopy, bio- and scanning imaging, structural biology crystallography, coherent techniques, or in-situ/operando methods. A dedicated session concerned industrial applications of synchrotron radiation.The field of synchrotron radiation instrumentation is currently seeing very active development due to various factors. Firstly, the number of SR sources world-wide is increasing significantly, with new sources in particular in Europe and in Asia. Secondly, a new generation of storage rings with new multi-bend achromat lattices are being implemented at a growing number of existing facilities. These facilities offer a significant increase of brilliance and coherence and thereby lead to new and improved applications of synchrotron radiation, in particular in the areas of imaging and high spatial resolution. Thirdly, the increase of soft and hard X-ray FEL sources worldwide and the maturation of their experimental techniques and scientific applications is the background for a strongly increasing number of developments for ultrafast time-resolved investigations of dynamic behaviour of materials and reactions. Most of the keynote speakers and many invited and contributed talks or posters at the conference showed new results directly related to these three major developments.Lists of International Advisory Committee (listed by facility), Scientific Programme Committee (listed by facility), Local Organising Committee (listed by facility) are available in this PDF.
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Purpose: Fiberoptic endoscopic evaluation of swallowing (FEES) is a well-respected swallowing assessment, harking back to 1988 when it was first published by Susan Langmore as a procedure. Since then, its methodology has evolved to afford clinicians, researchers, and patients a sensitive, specific, and predictive exam. A myriad research has investigated FEES technique and its outcomes, rendering it an effective and efficient procedure for swallowing assessment and therapy. This commentary will outline evidence for FEES to support evidence-based practice. What is the evidence for speech tasks? Secretion scales? What is the predictive nature of aspiration as seen on FEES? This comprehensive review will outline the science bolstering the use and confidence in FEES. Conclusions: This commentary reviews studies that have proposed normative data collected via FEES for decision making, specifically when assessing pharyngeal and laryngeal anatomy, bolus spillage, and the white out period. Evidence for FEES sensitivity and predictive aspects are reviewed in relationship to speech tasks, secretions, aspiration and penetration--aspiration scale scores, and pharyngeal residue scales. The acute care advantage of FEES is defined in its use on postextubation populations, assessment of dysphagia in COVID-19 positive patients, and safe evaluation during ice chip administration with acutely ill patients. Finally, inference making on FEES is discussed in regard to epiglottic retroflexion and depth of aspiration. When it comes to assessing pharyngeal dysphagia, the true strengths of FEES are rooted in evidence. It has been shown to be sensitive, predictive, and practical and will likely continue to have stronger support as research continues to enrich its potential.
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Highly infectious viral diseases are a serious threat to mankind as they can spread rapidly among the community, possibly even leading to the loss of many lives. Early diagnosis of a viral disease not only increases the chance of quick recovery, but also helps prevent the spread of infections. There is thus an urgent need for accurate, ultrasensitive, rapid, and affordable diagnostic techniques to test large volumes of the population to track and thereby control the spread of viral diseases, as evidenced during the COVID-19 and other viral pandemics. This review paper critically and comprehensively reviews various emerging nanophotonic biosensor mechanisms and biosensor technologies for virus detection, with a particular focus on detection of the SARS-CoV-2 (COVID-19) virus. The photonic biosensing mechanisms and technologies that we have focused on include: (a) plasmonic field enhancement via localized surface plasmon resonances, (b) surface enhanced Raman scattering, (c) nano-Fourier transform infrared (nano-FTIR) near-field spectroscopy, (d) fiber Bragg gratings, and (e) microresonators (whispering gallery modes), with a particular emphasis on the emerging impact of nanomaterials and two-dimensional materials in these photonic sensing technologies. This review also discusses several quantitative issues related to optical sensing with these biosensing and transduction techniques, notably quantitative factors that affect the limit of detection (LoD), sensitivity, specificity, and response times of the above optical biosensing diagnostic technologies for virus detection. We also review and analyze future prospects of cost-effective, lab-on-a-chip virus sensing solutions that promise ultrahigh sensitivities, rapid detection speeds, and mass manufacturability.
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Physics II is an undergraduate course on basic electromagnetism that I teach for engineers, and it includes topics from optics as a natural application. Among the many challenges of conducting video lectures during the local restrictions of the SARS-CoV-2 epidemic was finding demonstration material. In this article, I describe how these restrictions led me to develop my home version of Michelson's experiment as an alternative to Young's, and how I was able to highlight the circumstances in which both experiments turn out to be two particular cases of the same underlying idea. [ FROM AUTHOR]