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1

Scholz, Dieter. "Routes of Aircraft Cabin Air Contamination from Engine Oil, Hydraulic and Deicing Fluid." INCAS Bulletin 14, no. 1 (2022): 153–70. https://doi.org/10.13111/2066-8201.2022.14.1.13.

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<strong>Purpose</strong>: This paper discusses potential contamination of the air in passenger aircraft cabins. It gives an overview of cabin air contamination basics. It further names possible contamination sources and possible routes of contamination. <strong>Methodology</strong>: Evidence follows from a review of material found on the Internet and from the documentation of a visit to an aircraft recycling site. Parts were retrieved at the site and investigated later with more time. <strong>Findings</strong>: Jet engine seals leak oil in small quantities. Metallic nanoparticles are found in the oil and have been detected in human fatty tissue of aviation workers. It has been observed that the potable water on board can also be contaminated. Oil traces have been found in bleed ducts, air conditioning components, and in air conditioning ducts. Deicing fluid and hydraulic fluid can find their way into the air conditioning system via the APU air intake. Fuel and oil also leak down onto the airport surfaces. These fluids can be ingested by the engine from the ground and can enter the air conditioning system from there. Entropy is the law of nature that states that disorder always increases. This is the reason, why it is impossible to confine engine oil and hydraulic fluids to their (predominantly) closed aircraft systems. This is why engine oil with metal nanoparticles hydraulic fluids, and deicing fluids eventually can go everywhere and finally into the human body. <strong>Research Limitations</strong>: No measurements have been made. <strong>Practical Implications</strong>: Awareness and prevention of contaminated cabin air can protect passengers and crew. <strong>Social Implications</strong>: The exposure of contaminated cabin air provides a basis for a general discussion and shows that people should be alerted and need to act. New technologies need to be implemented such as a bleed free architecture. <strong>Originality</strong>: This paper shows many original images of contaminated parts and air ducts between engine compressor and cabin air outlet. Own observations are combined with similar observations found in literature and online. The collected evidence is visualized in a diagram showing the routes of possible aircraft cabin air (and water) contamination.
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Gabelli, Sandra, Ampon Saeher, and Jill Chrencik. "#IAmRemarkable." Structural Dynamics 12, no. 2_Supplement (2025): A343. https://doi.org/10.1063/4.0000649.

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In recent years, there has been a growing recognition of the importance of self-promotion and self-advocacy, particularly for underrepresented groups in various professional fields. The #IAmRemarkable initiative aims to empower individuals to speak openly about their accomplishments and combat societal norms that often discourage self-promotion, particularly among women and other marginalized groups. At ACA2024, we are excited to offer a special session dedicated to the #IAmRemarkable movement. This session will provide participants with the opportunity to explore the significance of self-promotion, challenge self-limiting beliefs, and develop strategies for effectively communicating their achievements. The session will include interactive discussions, guided exercises, and real-world examples to inspire and empower participants to embrace their accomplishments and share their stories confidently. Attendees will leave with a renewed sense of self-worth and a toolkit of skills to help them amplify their voices and make a positive impact in their professional lives. In recent years, there has been a growing recognition of the importance of self-promotion and self-advocacy, particularly for underrepresented groups in various professional fields. The #IAmRemarkable initiative aims to empower individuals to speak openly about their accomplishments and combat societal norms that often discourage self-promotion, particularly among women and other marginalized groups. At ACA2024, we are excited to offer a special session dedicated to the #IAmRemarkable movement. This session will provide participants with the opportunity to explore the significance of self-promotion, challenge self-limiting beliefs, and develop strategies for effectively communicating their achievements. The session will include interactive discussions, guided exercises, and real-world examples to inspire and empower participants to embrace their accomplishments and share their stories confidently. Attendees will leave with a renewed sense of self-worth and a toolkit of skills to help them amplify their voices and make a positive impact in their professional lives.
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3

Robbins, Stuart J. "Inconsistency between the Ancient Mars and Moon Impact Records of Megameter-scale Craters." Planetary Science Journal 3, no. 12 (2022): 274. http://dx.doi.org/10.3847/psj/aca282.

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Abstract Impact crater populations provide a record of the bombardment history of a planetary body. These craters reveal an intense bombardment history on Earth's Moon that included significant, large impacts, at least four of which created craters larger than ∼1000 km across more than 3.7 Ga. Scaling the lunar impact crater history to Mars using generally well-established scaling rules indicates Mars should have ∼40–80 similarly sized, ancient craters. However, Mars has roughly seven. This is a nontrivial mismatch between observation and expectation. Possible methods to resolve the mismatch are discussed in this work: small number statistics, incorrect scaling laws, heat flow produced larger-than-expected craters, the ratio of Mars:Moon impactors was different in early solar system history, Mars’s ancient crater chronology is wrong, and/or Mars has hidden a large fraction of its large impacts. None of these scenarios are mutually exclusive. This work details how the different scenarios could work to bring observations more in-line with the scaling expectations, or vice versa. It is posited that the most likely sources of the mismatch are that the initial bolide rate was different (this is a noncontroversial supposition), that lunar heat flow produced larger craters than expected, and the formation of the Martian Borealis basin could have kept the surface warm enough for long enough to prevent large features from forming for an extended period of time. The primary purpose of this work is to present the issue with possible ways to solve it through future efforts.
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4

Zhu, Yifeng, Xinhua Fu, and Lintao Yu. "Simultaneous red, green and blue laser operations in a Pr3+:LiYF4 crystal." Laser Physics 33, no. 1 (2022): 015001. http://dx.doi.org/10.1088/1555-6611/aca292.

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Abstract We report on the first, to the best of our knowledge, simultaneous continuous-wave red, green and blue laser operations in praseodymium-doped crystalline materials. At an absorbed pump power of 4.7 W (or 10 W of incident pump power), the maximum output power was 665 mW, which included 607 nm (red), 523 nm (green) and 479 nm (blue) three wavelengths, and the optical conversion efficiency with respect to the absorbed pump power was 14.1%.
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5

Razhev, A. M., E. S. Kargapol `tsev, D. S. Churkin, and I. A. Trunov. "Pulsed inductive CO2 laser with radio-frequency excitation and influence of the H2 content on the efficiency and lasing temporal characteristics." Laser Physics 33, no. 1 (2022): 015002. http://dx.doi.org/10.1088/1555-6611/aca291.

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Abstract In 2021, data on the effective pulsed gas discharge inductive CO2 laser with radio-frequency (RF) excitation were published with a pulse output energy of E∼ 1 J (the efficiency η∼ 14.5%) on the gas mixture He:N2:CO2 = 8:2:1. The efficiency of the developed CO2 laser had exceeded the value η∼ 21% at E∼ 350 mJ. At the beginning of 2022, it was shown that xenon addition (Xe = 4%) to the gas mixture made it possible to achieve an efficiency of η∼ 27% at an output energy of E∼ 600 mJ. For the first time, the effect of hydrogen additives in the active medium (He:N2:CO2:H2 and N2:CO2:H2 gas mixtures) was investigated for a pulsed inductive CO2 laser with RF excitation depending on the RF-pumping pulse duration value (τ), which allows the energy and temporal radiation characteristics of the laser to be controlled over a wider range. In addition to those already published, new experimental data have been obtained, namely the output beam profile of the inductive CO2 laser based on He:N2:CO2 = 8:2:1 gas mixture depending on the τ value. The new data will improve our understanding of inductive CO2 laser physics and of the plasma–chemical processes occurring in its active medium. RF current pulses propagated along inductor wires and, thus, an inductive discharge was formed to create a population inversion by IR transitions of CO2 * molecules.
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6

Haga, Taiki, and Shin-ich Sasa. "Interscale entanglement production in a quantum system simulating classical chaos." Journal of Statistical Mechanics: Theory and Experiment 2022, no. 12 (2022): 123102. http://dx.doi.org/10.1088/1742-5468/aca2a1.

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Abstract It is a fundamental problem how the universal concept of classical chaos emerges from the microscopic description of quantum mechanics. We here study standard classical chaos in a framework of quantum mechanics. In particular, we design a quantum lattice system that exactly simulates classical chaos after an appropriate continuum limit, which is called the ‘Hamiltonian equation limit’. The key concept of our analysis is an entanglement entropy defined by dividing the lattice into many blocks of equal size and tracing out the degrees of freedom within each block. We refer to this entropy as the ‘interscale entanglement entropy (IEE)’ because it measures the amount of entanglement between the microscopic degrees of freedom within each block and the macroscopic degrees of freedom that define the large-scale structure of the wave function. By numerically simulating a quantum lattice system corresponding to the Hamiltonian of the kicked rotor, we find that the long-time average of the IEE becomes positive only when chaos emerges in the Hamiltonian equation limit, and the growth rate of the entropy in the initial stage is proportional to that of the coarse-grained Gibbs entropy of the corresponding classical system.
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7

Nunes, Pollyanna Vicente, and Fábio Armando Tal. "Transitivity and the existence of horseshoes on the 2-torus." Nonlinearity 36, no. 1 (2022): 199–230. http://dx.doi.org/10.1088/1361-6544/aca252.

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Abstract We study the relationship between transitivity and topological chaos for homeomorphisms of the two torus. We show that if a transitive homeomorphism of T 2 is homotopic to the identity and has both a fixed point and a periodic point which is not fixed, then it has a topological horseshoe. We also show that if a transitive homeomorphisms of T 2 is homotopic to a Dehn twist, then either it is aperiodic or it has a topological horseshoe.
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8

Borsato, Riccardo, and Emanuel Malek. "Integrability, dualities and deformations." Journal of Physics A: Mathematical and Theoretical 55, no. 46 (2022): 460301. http://dx.doi.org/10.1088/1751-8121/aca22f.

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Abstract We present a special issue reviewing various topics that include: classical and quantum integrability, integrable deformations, the 4D Chern–Simons theory, double field theory and α ′ -corrections in string theory.
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9

Middei, Riccardo, Ioannis Liodakis, Matteo Perri, et al. "X-Ray Polarization Observations of BL Lacertae." Astrophysical Journal Letters 942, no. 1 (2022): L10. http://dx.doi.org/10.3847/2041-8213/aca281.

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Abstract Blazars are a class of jet-dominated active galactic nuclei with a typical double-humped spectral energy distribution. It is of common consensus that the synchrotron emission is responsible for the low frequency peak, while the origin of the high frequency hump is still debated. The analysis of X-rays and their polarization can provide a valuable tool to understand the physical mechanisms responsible for the origin of high-energy emission of blazars. We report the first observations of BL Lacertae (BL Lac) performed with the Imaging X-ray Polarimetry Explorer, from which an upper limit to the polarization degree Π X &lt; 12.6% was found in the 2–8 keV band. We contemporaneously measured the polarization in radio, infrared, and optical wavelengths. Our multiwavelength polarization analysis disfavors a significant contribution of proton-synchrotron radiation to the X-ray emission at these epochs. Instead, it supports a leptonic origin for the X-ray emission in BL Lac.
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10

Xu, Han, Xiangxia Ren, Weiguo Song, Jun Zhang, and Rayyan Saidahmed. "Spatial and temporal analysis of the bottleneck flow under different walking states with a moving obstacle." Journal of Statistical Mechanics: Theory and Experiment 2023, no. 1 (2023): 013401. http://dx.doi.org/10.1088/1742-5468/aca2a2.

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Abstract The regulation of a moving obstacle on crowd movement offers the possibility to enhance evacuation efficiency in emergency situations. In this paper, a series of controlled experiments are conducted to study the effect of the moving obstacle on crowd dynamics for pedestrians in three different competitive levels, which respectively correspond to three different walking states. The enhancement effects of the moving obstacle on evacuation efficiency for the crowd in the dual-task and high-motivated walking states are confirmed, and the positions of the moving obstacle are crucial. It is found that the moving obstacle diminishes the order of the trajectories for the crowd in the dual-task and normal walking states, while it boosts near the exit for the crowd in the high-motivated walking state. And the moving obstacle makes the linear backward propagations of stop-and-go wave disappear for the crowd in the dual-task and high-motivated walking states, but the frequency of stop behavior increases for the crowd in the dual-task and normal walking states. The profiles of evacuation time show that the moving obstacle impedes the pedestrian flow from the front of the exit and increases evacuation efficiency for the pedestrians near the walls of the exit. The analysis of time headway suggests that the moving obstacle with a gap of 1.0 m or 1.2 m to the exit can reduce the number of the pedestrians waiting near the exit for the crowd in the dual-task and high-motivated walking states. Besides, the gap of 0.8 m between the moving obstacle and the exit makes the conflicts at the exit is increased, but the gap of 1.0 m or 1.2 m makes the number of conflicts at the exit be reduced. This study helps the evacuation management of dense crowds and improves the design of facilities to facilitate pedestrian traffic.
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11

Grishacheva, T. G. "Influence of photoactivated coproporphirin on microcirculation." Regional blood circulation and microcirculation 17, no. 4 (2019): 75–80. http://dx.doi.org/10.24884/1682-6655-2018-17-4-75-80.

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The aim –to investigate the effect of photoactivated coproporphyrin III (KP III) on microcirculation in the rat mesenteric vascular bed. Material and methods. The study was performed on 20 male rats, divided into 4 groups: 1) control; 2) KP III; 3) laser irradiation; 4) laser irradiation on combined with prior administration of the KP III.The objectof the study was venules (20–40 µm) of the mesentery of the small intestine. The study of blood flow velocity in the venules was performed using the method of intravital biomicroscopy. The velocity parameters were registered using a high-speed video camera Basler acA2000 (Germany). Coproporphyrin III (Elast, Russia) at a dose of 10 mg/kg was injected into the tail vein 3 hours before laser irradiation. Irradiation was performed using a Lakhta Milon semiconductor laser apparatus (Qualitek, Russia) (λ=635 nm, 0.1 W/cm2 ; 300 s; 30 J/cm2 ).Results.Administration of KP III without subsequent irradiation did not affect the blood flow velocity during the entire observation period. Laser irradiation of venules without prior administration of KP III led to an increase in blood flow velocity by 39.1 % (p&lt;0.05). After laser irradiation and administration of KPIII, there was a gradual decrease in flow velocity after the photoactivation process.Conclusions. We studied the effect of photoactivated KP III on microcirculation in the mesentery of the small intestine of rats. Changes in the blood flow velocity in the venules of the mesentery affected by KP III and laser irradiation develop mainly in the post-radiation period and could be associated with endothelial dysfunction.
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12

Herranz Olazábal, Jorge, Fokko Wieringa, Evelien Hermeling, and Chris Van Hoof. "Camera-Derived Photoplethysmography (rPPG) and Speckle Plethysmography (rSPG): Comparing Reflective and Transmissive Mode at Various Integration Times Using LEDs and Lasers." Sensors 22, no. 16 (2022): 6059. http://dx.doi.org/10.3390/s22166059.

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Background: Although both speckle plethysmography (SPG) and photoplethysmography (PPG) examine pulsatile changes in the vasculature using opto-electronics, PPG has a long history, whereas SPG is relatively new and less explored. The aim of this study was to compare the effects of integration time and light-source coherence on signal quality and waveform morphology for reflective and transmissive rSPG and rPPG. Methods: (A) Using time-domain multiplexing, we illuminated 10 human index fingers with pulsed lasers versus LEDs (both at 639 and 850 nm), in transmissive versus reflective mode. A synchronized camera (Basler acA2000-340 km, 25 cm distance, 200 fps) captured and demultiplexed four video channels (50 fps/channel) in four stages defined by illumination mode. From all video channels, we derived rPPG and rSPG, and applied a signal quality index (SQI, scale: Good &gt; 0.95; Medium 0.95–0.85; Low 0.85–0.8; Negligible &lt; 0.8); (B) For transmission videos only, we additionally calculated the intensity threshold area (ITA), as the area of the imaging exceeding a certain intensity value and used linear regression analysis to understand unexpected similarities between rPPG and rSPG. Results: All mean SQI-values. Reflective mode: Laser-rSPG &gt; 0.965, LED-rSPG &lt; 0.78, rPPG &lt; 0.845. Transmissive mode: 0.853–0.989 for rSPG and rPPG at all illumination settings. Coherent mode: Reflective rSPG &gt; 0.951, reflective rPPG &lt; 0.740, transmissive rSPG and rPPG 0.990–0.898. Incoherent mode: Reflective all &lt;0.798 and transmissive all 0.92–0.987. Linear regressions revealed similar R2 values of rPPG with rSPG (R2 = 0.99) and ITA (R2 = 0.98); Discussion: Laser-rSPG and LED-rPPG produced different waveforms in reflection, but not in transmission. We created the concept of ITA to investigate this behavior. Conclusions: Reflective Laser-SPG truly originated from coherence. Transmissive Laser-rSPG showed a loss of speckles, accompanied by waveform changes towards rPPG. Diffuse spatial intensity modulation polluted spatial-mode SPG.
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Glynn, P. J., and A. L. Pulsford. "Isolation and partial characterisation of the serum immunoglobulin of the flounder, Platichthys flesus." Journal of the Marine Biological Association of the United Kingdom 70, no. 2 (1990): 429–40. http://dx.doi.org/10.1017/s0025315400035517.

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Whole flounder serum has been fractionated by gel filtration on Ultrogel AcA22. Pooled material from the first major peak of the elution profile was further fractionated by FPLC ion-exchange chromatography and this yielded one major and three minor peaks. Under both reducing and non-reducing conditions SDS electrophoresis showed that the major peak and two of the minor ones were immunoglobulin (Ig). All three of these Ig populations were tetrameric, with estimated molecular weights of 710 kD. However, approximately 90% of the major Ig species consisted of tetramers which were covalently linked by disulphide bonds, whereas the remaining 10% was composed of dimeric molecules held together by non-covalent interactions. The heavy chains of all three Ig populations had apparent molecular weights of approximately 72 kD but the light chain composition showed considerable heterogeneity. In the major population, five polypep-tides were detected in the light chain region of the gel with apparent molecular weights covering the range 22–28 kD. However, there was no difference in the light chain composition of covalently and non-covalently linked tetramers. The two minor populations differed both from each other and from the major species in respect of their light chain compositions. No evidence was found for a monomeric serum Ig, and alkaline urea electrophoresis failed to demonstrate a J chain.
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Гришачёва, Т. Г., И. А. Михайлова, Н. Н. Петрищев, А. И. Кривченко, and А. В. Струй. "Monitoring blood flow velocity in rat mesenteric venules." ZHurnal «Patologicheskaia fiziologiia i eksperimental`naia terapiia», no. 3() (September 16, 2020): 156–62. http://dx.doi.org/10.25557/0031-2991.2020.03.156-162.

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Разработка систем для регистрации и автоматической обработки информации о непосредственной реакции микрососудов на различные факторы является важной задачей для доклинического испытания новых препаратов, воздействующих на систему микроциркуляции. Цель исследования - модификация метода on-line-регистрации и обработки интравитальных изображений микрососудов для изучения динамики скорости кровотока при возмущающих воздействиях. Методика. Представлена усовершенствованная методика регистрации скоростей линейного кровотока в микрососудах и обработки интравитальных изображений. Для визуальной фиксации изменения скорости кровотока использовали макроскоп (Wild M420, Швейцария), объектив (Makrozoom 6.3-32х), быстродействующую цифровую камеру (Basler acA2000-165uc USB3.0, Германия) c матрицей CMOSIS CMV2000. Камера позволяет получать полнокадровые изображения 2000×1000 пикселей с частотой 165 кадров/с, а линейные изображения с частотой 8000 кадров/с, что позволяет фиксировать достаточно широкий диапазон линейных скоростей кровотока. Масштаб полученного с помощью системы «микроскоп - камера изображения» составляет 0,7 микрона на пиксел, что дает возможность измерения скоростей от 0,1 до 150 мм/с. В работе был использован метод оцифровки и анализа изображений на основе пакета программ «МультиМедиа Каталог» версии 2.3 («MMCatalog», Россия). Анализ скорости кровотока основан на непосредственном измерении скорости движения потока клеток крови. При измерении скорости определяется смещение потока клеток крови между двумя измерениями через заданный промежуток времени. Для этого на изображение кровотока в выбранном участке микрососуда наносится линейный маркер, ориентированный вдоль русла сосуда. После запуска процесса измерений камера каждую секунду переводится в режим линейной съемки вдоль маркера. Производится съемка серии из 5-6 измерений линейных изображений с заданным интервалом времени, по ним строятся оптические срезы и измеряется относительное смещение кривой. Смещение кривой определяется методом оценки суммы разностей одного массива яркостей графика от другого при сканировании от -20 до +20% от текущей позиции. Позиция, соответствующая минимальной сумме разностей, считается величиной смещения графиков. Эта процедура проводится для всех 5-6 пар измерений. Из полученных значений смещения графиков выбирается медиана, которая и используется как результат измерения скорости. Затем камера опять переводится в режим съемки полнокадровых изображений, что позволяет контролировать положение маркера в реальном времени. Во время эксперимента могут происходить перемещения объекта из-за движения или дыхания животного. Для корректировки положения маркера на изображении сосуда есть возможность изменения его позиции во время измерений. Программа фиксирует полученные значения смещения графиков и, как следствие, скорость кровотока. В зависимости от скорости кровотока программа позволяет регулировать число измерений в единицу времени, что дает возможность поддерживать стабильность измерения скорости. Для снижения влияния высокочастотного шума проводится сглаживание графиков с помощью скользящего усреднения. Интенсивность усреднения регулируется в процессе измерений. Регистрация скорости кровотока в выбранном участке проводится непрерывно в течение всего эксперимента. Схема проведения эксперимента: - запись исходного кровотока в течение 180 с; - регистрация кровотока во время лазерного облучения - 300 с; - регистрация кровотока после воздействия - 300 с. Результаты. Данный способ регистрации скорости кровотока позволяет фиксировать повышение скорости кровотока в венулах как во время воздействия лазерным излучением (662 нм), так и после завершения облучения. Заключение. Предложенная методика обработки интравитальных изображений кровотока дает возможность регистрации в режиме реального времени быстрых изменений скорости кровотока в микрососудах при возмущающих воздействиях. Development of systems for recording and automatic processing of information about direct microvascular responses is an important task for a preclinical study of drugs influencing the microcirculation. The aim was to modify the method for on-line recording and processing of intravital images of microvessels to study changes in the blood flow velocity under disturbing impacts. Method. This article presents an improved technique for recording linear blood flow velocity in microvessels and for processing intravital images. Macroscope (Wild M420, Switzerland), lens (Makrozoom 6.3-32x), and high-speed digital camera (Basler acA2000-165uc USB3.0, Germany) with a CMOSIS CMV2000 matrix were used for visual tracking of changes in blood flow velocity. The camera allows obtaining full-frame, 2000x1000 pixel images with a frequency of 165 fps, and linear images with a frequency of 8000 fps to capture a wide range of linear blood flow velocities. The scale of an image obtained with the microscope-camera system is 0.7 microns per pixel, which makes it possible to measure velocities of 0.1 to 150 mm/s. Digitizing and analyzing images were performed with a MultiMedia Catalog software, Version 2.3 (MMCatalog, Russia). The analysis of blood flow velocity is based on direct measurement of the blood cell flow velocity. The velocity is measured by estimation of the shift of blood cell flow for a predetermined time period between two measurements. To this purpose, a linear marker oriented along the vessel is applied to the blood flow image in a selected section of the microvessel. Following the measurement onset, the camera switches to a linear mode along the marker every second. A series of 5-6 measurements of linear images is taken at definite time intervals. Then measurements are used for construction of optical slices and measurement of the relative shift of the curve. The curve shift is determined by estimating the sum of differences between two arrays of curve brightness in scanning from -20 to +20% of the current position. The position corresponding to the minimum sum of differences is considered the value of curve shift. This procedure is performed for all 5-6 pairs of measurements. From the obtained values of curve shifts a median is selected, which is used as a result of measuring the velocity. Then the camera is again switched to the full-frame shooting mode, which allows you to control the position of the marker in real time. During the experiment, the object may move due to movements or breathing of the animal. To adjust the marker position on the image, it is possible to change its position during the measurements. The program captures the obtained values of curve shits and, thereby, the blood flow velocity. Based on the blood flow velocity, the program allows adjusting the number of measurements per unit time, which makes it possible to maintain stability of velocity measurements. To reduce the effect of high-frequency noise the curves are smoothed using moving averages. The averaging intensity can be adjusted in the process of measurement. Recording of blood flow velocity in a selected area is performed continuously during the entire experiment. Experimental protocol: - recording of the initial blood flow for 180 s; - recording of blood flow during laser irradiation for 300 s; - recording of blood flow after the exposure for 300 s. Results. This method of recording blood flow velocity allows recording increases in venular blood flow velocity both during and after an exposure to laser irradiation (662 nm). Conclusion. The proposed technique for processing intravital images of blood flow makes it possible to record fast changes in blood flow velocity in microvessels under disturbing impacts in real time.
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Bernardez Moreno, J., L. Berbel Arcobe, J. L. Tandaipan Jaime, et al. "AB0710 STUDY OF THE GASTROINTESTINAL INVOLVEMENT IN PATIENTS WITH SYSTEMIC SCLEROSIS." Annals of the Rheumatic Diseases 81, Suppl 1 (2022): 1481.2–1482. http://dx.doi.org/10.1136/annrheumdis-2022-eular.3782.

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BackgroundSystemic Sclerosis (SSc) is a systemic autoimmune disease in which the gastrointestinal (GI) manifestation is one of the most frequent complications (90%), being esophagus and anorectal the most affected regions. The set of GI symptoms poses a diagnostic and therapeutic challenge, and the “Patient Reported Outcomes” (PRO) are good tools to address them. The UCLA GIT 2.0 validated questionnaire can be used as an instrument to measure the presence and severity of these symptoms, allowing screening, and improving subsequent management.ObjectivesTo describe gastrointestinal (GI) involvement in patients with SSc.MethodsDescriptive cross-sectional study conducted in a cohort of patients with SSc in a tertiary hospital. Sociodemographic, clinical, complementary tests and treatment variables were collected. Patients with established GI involvement needed to have urdergone some previous diagnostic test. The UCLA GIT 2.0 questionnaire was applied to all included patients, considering the presence of mild symptoms with a score of 0-0.49, moderate 0.49-1, and severe 1-3.Results88 patients (90% women) were recruited, with a mean age of 61.3 years. They presented the subtypes of limited and diffuse SSc in 63.3% and 13.6%, respectively. The most frequent antibodies were anticentromere (ACA) in 52.3% of the patients, anti-Ro52 in 20.5% and anti-topoisomerase I in 14.8%. The most frequent manifestations were Raynaud’s phenomenon in 98.8% of the patients followed by GI in 37.5% (gastro-esophageal reflux in 88.2%), diffuse interstitial lung disease in 18% and pulmonary hypertension in 10.22%. The most used treatment was proton pump inhibitors (PPI) in 47.7% of the patients.Patients with GI involvement presented the limited SSc subtype (72.7%) and ACA (60.6%) as main characteristics. Patients without digestive involvement had similar characteristics, but did not show a greater association with any specific antibody (p=0.321).67% of the total number of patients presented a score greater than 0 in the UCLA GIT 2.0 questionnaire, with the reflux section being the most frequent (52.27%). In relation to the total score, they presented mild, moderate, and severe symptoms in 77.3%, 21.6% and 1.1% of the patients respectively. The rest of the results by categories are summarized in Table 1.Table 1.Gastrointestinal involvement(n= 34)Without gastrointestinal involvement(n= 54)Subtype and antibodies Limited24 (70,58%)32 (59,25%) Diffuse5 (14,70%)7 (12,96%) ACA20 (58,82%)26 (48,14%) ATA5 (14,70%)8 (14,81%)Manifestations and treatment ILD5 (14,70%)11 (20,37%) PAH3 (8,82%)6 (11,11%) PPI31 (91,17%)11 (20,37%)UCLA GIT 2.0 (median) Total score0,300,05 Reflux0,350 Swelling0,620 Stain00 Diarrhea*00 Social functioning00 Emotional well-being0,220 Constipation Ɨ00ILD (intersticial lung disease), PAH (pulmonary arterial hypertension), ACA (anti-centromere), ATA (anti-topoisomerase), PPI (proton pump inhibitors).*In the “diarrhea” subcategory the maximum score is 2.Ɨ In the “constipation” subcategory the maximum score is 2,5.Patients with GI pathology presented higher scores (moderate-severe) compared to those without pathology (p=0.009). In this last group, 34.5% of the patients presented GI symptoms according to the test, observing high scores in the bloating, reflux, and constipation sections in 25.2%, 16.6% and 14.8% of the patients respectively.ConclusionGI involvement tends to be one of the most frequent manifestations in our cohort and occurs more frequently in patients with limited skin involvement and ACA +. Patients with established GI pathology had higher scores on the UCLA test. The questionnaire may be useful in detecting undiagnosed patients, but more studies are necessary to establish this possible correlation.References[1]Jose Luis Tandaipan, Ivan Castellví. Systemic sclerosis and gastrointestinal involvement. Rev Colomb Reumatol. 2020;27(S1):44-54.[2]Dinesh Khanna, et al. Measuring Response in the Gastrointestinal Tract in systemic sclerosis. Curr Opin Rheumatol. 2013;25(6).Disclosure of InterestsNone declared
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Anderson, Judith, and Dieter Scholz. "Oil Fumes, Flight Safety, and the NTSB." Aerospace, Special Issue Aircraft Design (SI-3/2021) 8, no. 12, paper 389 (2021). https://doi.org/10.3390/aerospace8120389.

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During its investigations into a series of ten aircraft crashes from 1979 to 1981, US National Transportation Safety Board (NTSB) officials were presented with a hypothesis that &ldquo;several&rdquo; of the crashes could have been caused by pilot impairment from breathing oil fumes inflight. The NTSB and their industry partners ultimately dismissed the hypothesis. The authors reviewed the crash reports, the mechanics of the relevant engine oil seals, and some engine bleed air data to consider whether the dismissal was justified. Four of the nine aircraft crash reports include details which are consistent with pilot impairment caused by breathing oil fumes. None of the tests of ground-based bleed air measurements of a subset of oil-based contaminants generated in the engine type on the crashed aircraft reproduced the inflight conditions that the accident investigators had flagged as potentially unsafe. The NTSB&rsquo;s conclusion that the hypothesis of pilot incapacitation was &ldquo;completely without validity&rdquo; was inconsistent with the evidence. Parties with a commercial conflict of interest should not have played a role in the investigation of their products. There is enough evidence that pilots can be impaired by inhaling oil fumes to motivate more stringent design, operation, and reporting regulations to protect safety of flight.
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17

Tang, Di, Jinqi Che, Weijie Jin, et al. "Quantitative analysis of the morphing wing mechanism of raptors: morphing kinematics of Falco peregrinus wing." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca201.

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Abstract Raptors are getting more attention from researchers because of their excellent flight abilities. And the excellent wing morphing ability is critical for raptors to achieve high maneuvering flight, which can be a good bionic inspiration for unmanned aerial vehicles design. However, morphing wing motions of Falco peregrinus with multi postures cannot be consulted since such a motion database was nonexistent. The aim of this study was, therefore, to fill this gap in wing morphing kinetics and to provide a reference for future comparative and functional studies. Wing skeleton of the Falco peregrinus was scanned using computed tomography (CT) approach to obtain nine critical postures, followed with motion analysis of each joint and bone. Based on the obtained motion database, a six-bar kinematic model was proposed to regenerate wing motions with a high fidelity.
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18

Fu, Xuanhao, and Xin Zhou. "The different roles of surfaces’ interaction on lattice mismatched/matched surfaces in facilitating ice nucleation." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca202.

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Abstract The freezing of water is one of the most common processes in nature and affects many aspects of human activity. Ice nucleation is a crucial part of the freezing process and usually occurs on material surfaces. There is still a lack of clear physical pictures about the central question how various features of material surfaces affect their capability in facilitating ice nucleation. Via molecular dynamics simulations, here we show that the detailed features of surfaces, such as atomic arrangements, lattice parameters, hydrophobicity, and function forms of surfaces’ interaction to water molecules, generally affect the ice nucleation through the average adsorption energy per unit-area surfaces to individual water molecules, while the lattice of surfaces mismatches that of ice. However, for the surfaces whose lattice matches ice, even the detailed function form of the surfaces’ interaction to water molecules can largely regulate the icing ability of these surfaces. This study provides new insights into understanding the diverse relationship between various microscopic features of different material surfaces and their nucleation efficacy.
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19

Ly, Keith, Tianruo Guo, David Tsai, et al. "Simulating the impact of photoreceptor loss and inner retinal network changes on electrical activity of the retina." Journal of Neural Engineering, November 11, 2022. http://dx.doi.org/10.1088/1741-2552/aca221.

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Abstract Objective: A major reason for poor visual outcomes provided by existing retinal prostheses is the limited knowledge of the impact of photoreceptor loss on retinal remodelling and its subsequent impact on neural responses to electrical stimulation. Computational network models of the neural retina assist in the understanding of normal retinal function but can be also useful for investigating diseased retinal responses to electrical stimulation. Approach: We developed and validated a biophysically detailed discrete neuronal network model of the retina in the software package NEURON. The model includes rod and cone photoreceptors, ON and OFF bipolar cell pathways, amacrine and horizontal cells and finally, ON and OFF retinal ganglion cells with detailed network connectivity and neural intrinsic properties. By accurately controlling the network parameters, we simulated the impact of varying levels of degeneration on retinal electrical function. Main results: Our model was able to reproduce characteristic monophasic and biphasic oscillatory patterns seen in ON and OFF neurons during retinal degeneration. Oscillatory activity occurred at 3 Hz with partial photoreceptor loss and at 6 Hz when all photoreceptor input to the retina was removed. Oscillations were found to gradually weaken, then disappear when synapses and gap junctions were destroyed in the inner retina. Without requiring any changes to intrinsic cellular properties of individual inner retinal neurons, our results suggest that changes in connectivity alone were sufficient to give rise to neural oscillations during photoreceptor degeneration, and significant network connectivity destruction in the inner retina terminated the oscillations. Significance: Our results provide a platform for further understanding physiological retinal changes with progressive photoreceptor and inner retinal degeneration. Furthermore, our model can be used to guide future stimulation strategies for retinal prostheses to benefit patients at different stages of disease progression, particularly in the early and mid-stages of retinal degeneration.
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20

QCAQE. "Aircraft Contaminated Air Supply: The Way Forward." Journal of Health and Pollution, Vol. 9, No. 24 (Dec. 2019), December 1, 2019, 3. https://doi.org/10.5281/zenodo.3566778.

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Aircraft air supplies in all current large passenger transport aircraft (apart from the Boeing 787), utilize non-filtered air (bleed air) drawn from the compressor stage of turbine engines to provide pressurization and breathing air. This design has been utilized since the 1950s and 60s. Synthetic jet engine oils and other fluids in aircraft systems are recognized and known to contaminate the bleed air supply, impacting flight safety, occupational and public health.
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21

Jeong, Hyunbeen, Jisung Kim, Jong-Mo Seo, and Andrea Neviani. "Neurostimulators for high-resolution artificial retina: ASIC design challenges and solutions." Journal of Neural Engineering, November 14, 2022. http://dx.doi.org/10.1088/1741-2552/aca262.

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Abstract Object: Neurostimulator is one of the most important part in artificial retina design. In this paper, we discuss the main challenges in the design of application-specific integrated circuit for high-resolution artificial retina and suggest corresponding solutions. Approach: Problems in the design of the neurostimulator for the existing artificial retina have not been solved yet are analyzed and solutions are presented. For verification of the solutions, mathematical proof, MATLAB and Ansys simulations are used. Main results: The drawbacks of resorting to a high-voltage CMOS process to deal with the large voltage compliance demanded by the stimulator output stage are pointed out, and an alternative approach based on a circuit that switches the voltage of the common reference electrode is proposed to overcome. The necessity of an active discharge circuit to remove the residual charge of electrodes caused by an unbalanced stimulus is investigated. We present a circuit analysis showing that the use of a passive discharge circuit is sufficient to suppress problematic direct current in most situations. Finally, possible restrictions on I/O count are investigated by estimating the resistive-capacitive delay caused by the interconnection between the I/O pad and the microelectrode array. Significance: The results of this paper clarified the problems currently faced by neurostimulator design for the artificial retina. Through the solutions presented in this study, circuits with more competitiveness in power and area consumption can be designed.
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22

Bouillet, Thomas, Manuel Ciba, Caroline Lourenço Alves, et al. "Revisiting the involvement of tau in complex neural network remodeling: analysis of the extracellular neuronal activity in organotypic brain slice co-cultures." Journal of Neural Engineering, November 14, 2022. http://dx.doi.org/10.1088/1741-2552/aca261.

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Abstract Objective: Tau ablation has a protective effect in epilepsy due to inhibition of the hyperexcitability/hypersynchrony. Protection may also occur in transgenic models of Alzheimer’s disease by reducing the epileptic activity and normalizing the excitation/inhibition imbalance. However, it is difficult to determine the exact functions of tau, because tau knockout (tauKO) brain networks exhibit elusive phenotypes. In this study, we aimed to further explore the physiological role of tau using brain network remodeling. Approach: The effect of tau ablation was investigated in hippocampal-entorhinal slice co-cultures during network remodeling. We recorded the spontaneous extracellular neuronal activity over two weeks in single-slice cultures and co-cultures from control and tauKO mice. We compared the burst parameters and applied concepts and analytical tools intended for the analysis of the network synchrony and connectivity. Main results: Comparison of the control and tauKO co-cultures revealed that tau ablation had an anti-synchrony effect on the hippocampal-entorhinal two-slice networks at late stages of culture, in line with the literature. Differences were also found between the single-slice and co-culture conditions, which indicated that tau ablation had differential effects at the sub-network scale. For instance, tau ablation was found to have an anti-synchrony effect on the co-cultured hippocampal slices throughout the culture, possibly due to a reduction in the excitation/inhibition ratio. Conversely, tau ablation led to increased synchrony in the entorhinal slices at early stages of the co-culture, possibly due to homogenization of the connectivity distribution. Significance: The new methodology presented here proved useful for investigating the role of tau in the remodeling of complex brain-derived neural networks. The results confirm previous findings and hypotheses concerning the effects of tau ablation on neural networks. Moreover, the results suggest, for the first time, that tau has multifaceted roles that vary in different brain sub-networks.
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23

Chen, Zhongyong, Zhifang Lin, Wei Yan, et al. "Overview of runaway current suppression and dissipation on J-TEXT tokamak." Plasma Science and Technology, November 14, 2022. http://dx.doi.org/10.1088/2058-6272/aca272.

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Abstract The main works about disruption mitigation include suppression and mitigation of runaway current on the J-TEXT tokamak have been summarized in this paper. Two strategies for the mitigation of runaway electron beam have been applied in experiments. The first strategy enables the REs to be completely suppressed by means of supersonic molecular beam injection and resonant magnetic perturbation which can enhance REs loss, the magnetic energy transfer which can reduce the electric field, and the secondary massive gas injection (MGI) which can increase the collisional damping. For the second strategy, the runaway current will be allowed to be formed but should be dissipated or soft landed within tolerance. It has been observed that the runaway current can be significantly dissipated by MGI, and the dissipation rate increases with the injected impurity particle number and eventually stabilizes at 28 MA s−1. The dissipation rate of runaway current can be up to 3 MA s−1 by ohmic field. The shattered pellet injection has been chosen as the main disruption mitigation method, which has the capability of injecting material deeper into the plasma for higher density assimilation when compared to MGI. Besides, simulation works show that the RE seeds in the plasma have been strong influenced under different phases and sizes of 2/1 mode locked islands during the thermal quench. The robust runaway suppression and runaway current dissipation provide an important insight on the disruption mitigation for the future large tokamaks.
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24

Convy, Ian, and K. Birgitta Whaley. "Interaction Decompositions for Tensor Network Regression." Machine Learning: Science and Technology, November 14, 2022. http://dx.doi.org/10.1088/2632-2153/aca271.

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Abstract It is well known that tensor network regression models operate on an exponentially large feature space, but questions remain as to how effectively they are able to utilize this space. Using a polynomial featurization, we propose the interaction decomposition as a tool that can assess the relative importance of different regressors as a function of their polynomial degree. We apply this decomposition to tensor ring and tree tensor network models trained on the MNIST and Fashion MNIST datasets, and find that up to 75% of interaction degrees are contributing meaningfully to these models. We also introduce a new type of tensor network model that is explicitly trained on only a small subset of interaction degrees, and find that these models are able to match or even outperform the full models using only a fraction of the exponential feature space. This suggests that standard tensor network models utilize their polynomial regressors in an inefficient manner, with the lower degree terms being vastly under-utilized.
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25

Kumar, Rohit, and Satyabrata Adhikari. "Detection of d1 ⊗ d2 dimensional bipartite entangled state: a graph theoretical approach." Physica Scripta, November 11, 2022. http://dx.doi.org/10.1088/1402-4896/aca22c.

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Abstract Braunstein et. al. have started the study of entanglement properties of the quantum states through graph theoretical approach. Their idea was to start from a simple unweighted graph $G$ and then they have defined the quantum state from the Laplacian of the graph $G$. A lot of research had already been done using the similar idea. We ask here the opposite one i.e can we generate a graph from the density matrix? To investigate this question, we have constructed a unital map $\phi$ such that $\phi(\rho)=L_{\rho}+\rho$, where the quantum state is described by the density operator $\rho$. The entries of $L_{\rho}$ depends on the entries of the quantum state $\rho$ and the entries are taken in such a way that $L_{\rho}$ satisfies all the properties of the Laplacian. This make possible to design a simple connected weighted graph from the Laplacian $L_{\rho}$. We show that the constructed unital map $\phi$ characterize the quantum state with respect to its purity by showing that if the determinant of the matrix $\phi(\rho)-I$ is positive then the quantum state $\rho$ represent a mixed state. Moreover, we study the positive partial transpose (PPT) criterion in terms of the spectrum of the density matrix under investigation and the spectrum of the Laplacian associated with the given density matrix. Furthermore, we derive the inequality between the minimum eigenvalue of the density matrix and the weight of the edges of the connected subgraph of a simple weighted graph to detect the entanglement of $d_{1} \otimes d_{2}$ dimensional bipartite quantum states. Lastly, We have illustrated our results with few examples.
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26

Zheng, Qiwen, Wenguang Lu, Jiaqing Xu, Yunyang Ye, Xinmin Zhao, and Leyong Jiang. "Enhanced and controllable reflected group delay based on Tamm surface plasmons with Dirac semimetals." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca205.

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Abstract In this paper, the reflected group delay from a multilayer structure where bulk Dirac semimetals (BDS) is coated on one-dimensional photonic crystal (1D PC) separated by a spacer layer is investigated theoretically. It is shown that the group delay of reflected beam in this structure can be significant enhanced negatively and can be switched from negative to positive. The enhanced group delay originates from the steep phase change caused by the excitation of optical Tamm state (OTS) at the interface between the BDS and spacer layer. Moreover, the positive and negative group delay can be actively tuned through the Fermi energy and the relaxation time of the BDS. We believe that this enhanced and tunable delay scheme has important research significance for fabrication of optical delay devices.
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27

Cooper, Fred, Avinash Khare, Efstathios Georgios Charalampidis, John F. Dawson та Avadh B. Saxena. "Stability of exact solutions of the (2+1)-dimensional nonlinear Schröodinger equation with arbitrary nonlinearity parameter κ". Physica Scripta, 11 листопада 2022. http://dx.doi.org/10.1088/1402-4896/aca227.

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Abstract In this work, we consider the nonlinear Schrödinger equation (NLSE) in 2+ 1 dimensions with arbitrary nonlinearity exponent κ in the presence of an external confining potential. Exact solutions to the system are constructed, and their stability as we increase “mass” (i.e., the L2norm) and the nonlinearity parameter κ is explored. We observe both theoretically and numerically that the presence of the confining potential leads to wider domains of stability over the parameter space compared to the unconfined case. Our analysis suggests the existence of a stable regime of solutions for all κ as long as their mass is less than a critical value M*(κ). Furthermore, we find that there are two different critical masses, one corresponding to width perturbations and the other one to translational perturbations. The results of Derrick’s theorem are also obtained by studying the small amplitude regime of a four-parameter collective coordinate (4CC) approximation. A numerical stability analysis of the NLSE shows that the instability curve M*(κ) vs. κ lies below the two curves found by Derrick’s theorem and the 4CC approximation. In the absence of the external potential, κ = 1 demarcates the separation between the blowup regime and the stable regime. In this 4CC approximation, for κ &lt; 1, when the mass is above the critical mass for the translational instability, quite complicated motions of the collective coordinates are possible. Energy conservation prevents the blowup of the solution as well as confines the center of the solution to a finite spatial domain. We call this regime the “frustrated” blowup regime and give some illustrations. In an appendix, we show how to extend these results to arbitrary initial ground state solution data and arbitrary spatial dimension d.
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28

Ramaswamy, Radha, Sudhir Singh, C. Senthil Kumar, and Sen-yue Lou. "Elusive Exotic Structures and their Collisional Dynamics in (2+1)-Dimensional Boiti-Leon-Pempinelli Equation." Physica Scripta, November 11, 2022. http://dx.doi.org/10.1088/1402-4896/aca225.

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Abstract In this paper, we investigate the (2+1) dimensional Boiti-Leon-Pempinelli (BLP) equation employing truncated Painlev'{e} expansion approach and extract a plethora of localized nonlinear waves, including multi-dromions, multi-lumps, multi-rogue waves, generalized-breathers etc. The dromions are characterized as bright, dark and mixed (bright-dark) based on their intensity. The collisional dynamics of dromions shows that they change their shape or form upon interaction in addition to undergoing a phase change. The lump solutions of orders one and two are also extracted through appropriate test functions and observed to be non-interacting in nature. Also, the first-order and second-order rogue waves are also obtained through rational polynomials and shown to be unstable. The generalized breathers are obtained by utilizing the three-wave test function. The highlights of our investigation is that one encounters a strange coherent structure called ``dromion filter" which contains a dynamic and a stationary dromion. In addition, we are also able to unearth a ``coexistent dromion-line soliton".
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29

Zhou, Jie, Cheng Yuan, Zu-Yu Qian, Bing-Hong Wang, and Sen Nie. "Analysis of cut vertex in the control of complex networks." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca208.

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Abstract The control of complex networks is affected by their structural characteristic. As a type of key nodes in a network structure, cut vertexes are essential for network connectivity because their removal will disconnect the network. Despite their fundamental importance, the influence of cut vertexes on network control is still uncertain. Here, we reveal the relationship between cut vertexes and driver nodes, and find that driver nodes tend to avoid cut vertexes. However, driving cut vertexes reduces the energy required for controlling complex networks, since the cut vertexes are located near the middle of the control chains. By employing three different node failure strategies, we investigate the impact of cut vertexes failure on the energy required. The results show that cut vertex failures markedly increases the control energy because cut vertexes are larger-degree nodes. Our results deepen the understanding of the structural characteristic in network control.
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30

Wang, LiXiang, Yangyi Zhang, Chen Jiaming, et al. "Near-infrared light emitting devices from Er doped silica thin films via introducing SnO2 nanocrystals." Physica Scripta, November 11, 2022. http://dx.doi.org/10.1088/1402-4896/aca226.

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Abstract To get high performance light emitting devices on Si platform with emission wavelength at 1.55 μm is a challenge for future Si-based opto-electronic integration chips. In this paper, we fabricated near-infrared light-emitting devices based on Er/SnO2 co-doped silica thin films. The introduction of SnO2 nanocrystals with controllable size and density not only contributes to the near-infrared light emission enhancement of Er3+ ions at 1.55 μm, but also provides an effective carrier transport channelto realize efficient and stable electro-luminescence. The corresponding devices exhibit an external quantum efficiency of 5.4% at near infrared light region and the power efficiency is about 1.52 ×10-3. Our present work lays a solid foundation for facilitating Si-based light source towards practical application in the field of optoelectronic interconnection.
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31

Wang, Lin, Ke-Wen Xiao, Wen-Yuan Wang та Fu-quan Dou. "Quantum tunneling dynamics with robust reciprocity of Bose-Einstein condensate in a quadruple-well potential with synthetic gauge fields". Physica Scripta, 11 листопада 2022. http://dx.doi.org/10.1088/1402-4896/aca22a.

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Abstract Bose-Einstein condensation trapped in quadruple-well potential provides a great useful platform in theoretical and experimental researches. Utilizing analytical and numerical methods, we investigate the properties of quantum dynamics and the reciprocity of quantum transport of Bose-Einstein condensation (BEC) in quadruple-well potential formed by the laser-assisted transition. The tunneling dynamics of BEC is under the control of coupling between wells, dissipation, and the phase caused by Raman coupling laser. By adjusting the coupling phase, the coherent destruction of tunneling can be observed. Meanwhile, by testing the reciprocity of tunneling dynamics of BEC, this system provide a applicable proposal for reciprocal quantum switch by using the tunneling dynamics of BEC.
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32

Funane, Tsukasa, Yuki Yokoi, Masashi Kiguchi, et al. "Hemodynamic response to intestinal pH stimulation measured with spectroscopic video imaging." Biomedical Physics & Engineering Express, November 11, 2022. http://dx.doi.org/10.1088/2057-1976/aca20a.

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Abstract To investigate the relationship between the gut and skin (gut-skin axis), head skin hemodynamic responses to gut stimulation including the injection of acetic acid in nude mice were measured by spectroscopic video imaging, which was calculated using a modified Beer-Lambert formula. The relationship with blood proteins was also analyzed. The blood volume changes in three mice injected with acetic acid were highly reproducible in the mathematical model equation. Four proteins correlated with blood volume changes were all related to immunity. These results suggest that intestinal pH can alter the blood volume in the skin and induce immune-related responses.
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33

Xue, Hui, Hui Yuan, Kai Guo, and Mengmeng Zhang. "Effect of intermediate annealing on microstructure and mechanical property of a Fe-19Mn-0.6C TWIP steel." Materials Research Express, November 11, 2022. http://dx.doi.org/10.1088/2053-1591/aca241.

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Abstract Annealing is an effective strategy to improve the properties of high-strength twin-induced plasticity (TWIP) steels, however, the adaption of intermediate annealing during cold rolling (CR) is scarcely studied. Here, the Fe-19Mn-0.6C TWIP steel was subjected to CR-annealing and CR-intermediate annealing-CR-annealing processes at room temperature to determine the role of intermediate annealing in the improvement of microstructure and mechanical properties. The total cold-rolled reduction in both processes is 75%. The morphological and phase characterizations of the TWIP steel annealed for 1 h showed that uneven element distribution had occurred as the annealing temperature was greater than the recrystallization start temperature, causing the presence of minor carbides. Moreover, the carbides vanished at the recrystallization end temperature and were quantitatively analyzed content via the refined XRD. Finally, the recrystallized austenite grains completely replaced the cold-deformed microstructures. At the same total CR reduction of 75%, the TWIP steel exerted intermediate annealing facilitates the formation of twins, endowing the tensile strength vast increase. This would provide a significant reference to improve the mechanical properties of steels via annealing.
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34

Ferreira, Beatriz, Roberto Rosati, Jamie Fitzgerald, and Ermin Malic. "Signatures of dark excitons in exciton-polariton optics of transition metal dichalcogenides." 2D Materials, November 11, 2022. http://dx.doi.org/10.1088/2053-1583/aca211.

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Abstract Integrating 2D materials into high-quality optical microcavities opens the door to fascinating many-particle phenomena including the formation of exciton-polaritons. These are hybrid quasi-particles inheriting properties of both the constituent photons and excitons. In this work, we investigate the so-far overlooked impact of dark excitons on the momentum-resolved absorption spectra of hBN-encapsulated WSe$_2$ and MoSe$_2$ monolayers in the strong-coupling regime. In particular, thanks to the efficient phonon-mediated scattering of polaritons into energetically lower dark exciton states, the absorption of the lower polariton branch in WSe$_2$ is much higher than in MoSe$_2$. It shows unique step-like increases in the momentum-resolved profile indicating opening of specific scattering channels. We study how different externally accessible quantities, such as temperature or mirror reflectance, change the optical response of polaritons. Our study contributes to an improved microscopic understanding of exciton-polaritons and their interaction with phonons, potentially suggesting experiments that could determine the energy of dark exciton states via momentum-resolved polariton absorption.
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35

Gao, Qingqing, Yuchao Chen, and Lin Hu. "Effect of particle shape on the packing fraction and velocity profiles at the outlet of a silo." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca204.

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Abstract Many studies on how the particle shape affects the discharge flow mainly focus on discharge rates and avalanche statistics. In this study, the effect of the particle shape on the packing fractions and velocities of particles in the silo discharge flow was investigated by using discrete element method. The time-averaged packing fraction and velocity profiles through the aperture were systematically measured for superelliptical particles with different blockiness. Increasing the particle blockiness is found to increase resistance to flow and reduces the flow rate. At an identical outlet size, larger particle blockiness leads to lower velocities and packing fractions at the outlet. The packing fraction profiles display evident self-similar features that can be appropriately adjusted by fractional power laws. The velocity profiles for particles with different shapes obey a uniform self-similar law that is in accord with previous experimental results, which is compatible with the free fall arch hypothesis. To further investigate the origin of flow behaviors, the packing fraction and velocity fields in the region above the orifice were computed. Based on these observations, the flow rate of superelliptical particles was calculated and agrees with the simulated data.
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36

Liu, Haoguang, Jizhou He, and Jianhui Wang. "Performance optimization on finite-time quantum Carnot engines and refrigerators based on spin-1/2 systems driven by a squeezed reservoir." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca207.

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Abstract We investigate the finite-time performance of a quantum endoreversible Carnot engine cycle and its inverse operation-Carnot refrigeration cycle, employing a spin-$1/2$ system as the working substance. The thermal machine is alternatively driven by a hot boson bath of inverse temperature $\beta_h$ and a cold boson bath at inverse temperature $\beta_c(&gt;\beta_h)$. While for engine model the hot bath is constructed to be squeezed, in the refrigeration cycle the cold bath is established to be squeezed, with squeezing parameter $r$. We obtain the analytical expressions both for efficiency and power in heat engines and for coefficient of performance and cooling rate in refrigerators. We find that, in the high-temperature limit, the efficiency at maximum power is bounded by the analytical value, $\eta_+=1-\sqrt{{\rm{sech}}(2r)(1-\eta_C)}$, and the coefficient of performance at the maximum figure of merit is limited by $ \varepsilon_+=\frac{\sqrt{{\rm{sech}}(2r)(1+\varepsilon_C})}{\sqrt{{\rm{sech}}(2r)(1+\varepsilon_C)-\varepsilon_C}}-1$, where $\eta_C=1-\beta_h/\beta_c$ and $\varepsilon_C=\beta_h/(\beta_c-\beta_h)$ are the respective Carnot values of the engines and refrigerators, and $r$ is the squeezing parameter. These analytical results are identical to corresponding those obtained from the Carnot engines based on harmonic systems, indicating that the efficiency at maximum power and coefficient at maximum figure of merit are independent on the working substance.
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37

Miron, Asaf. "Local resetting with geometric confinement." Journal of Physics A: Mathematical and Theoretical, November 11, 2022. http://dx.doi.org/10.1088/1751-8121/aca22e.

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Abstract "Local resetting" was recently introduced to describe stochastic resetting in interacting systems where particles independently try to reset to a common "origin". Our understanding of such systems, where the resetting process is itself affected by interactions, is still very limited. One ubiquitous constraint that is often imposed on the dynamics of interacting particles is geometric confinement, e.g. restricting rigid spherical particles to a channel so narrow that overtaking becomes difficult. We here explore the interplay between local resetting and geometric confinement in a system consisting of two species of diffusive particles: "bath" particles, and "tracers" which undergo local resetting. Mean-field analysis and numerical simulations show that the resetting tracers, whose stationary density profile exhibits a typical "tent-like" shape, imprint this shape onto the bath density profile. Upon varying the ratio of the degree of geometric confinement over particle diffusivity, the system is found to transition between two states. In one tracers expel bath particles away from the origin, while in the other they ensnare them instead. Between these two states, we find a special case where the mean field approximation becomes exact.
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38

Cao, Yang, Jianjun Mei, Kai Xia, et al. "Solution-Based Fullerene-Free Route Enables High-Performance Green-Selective Organic Photodetectors." Journal of Physics: Materials, November 11, 2022. http://dx.doi.org/10.1088/2515-7639/aca222.

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Abstract Ongoing developments in machine vision, wearables, and the Internet of Things have led to strong demand for easy-to-fabricate, color-selective photodetectors. Narrowband-absorption-type (NBA) printable organic photodetectors provide an attractive solution, given their spectral robustness and fabrication simplicity. However, a key remaining challenge to realizing their potential is to concurrently achieve high photoconversion efficiency and spectral selectivity. Herein, this challenge is tackled by investigating a non-fullerene-based route to green-selective, solution-based photodetectors. Soluble phthalocyanine acceptor PhO-Cl6BsubPc is considered due to its high absorption selectivity to green photons. Blends with soluble quinacridones are pursued to realize the ideal of a donor:acceptor layer selectively absorbing the target photons throughout its volume. Amongst quinacridones, a latent-pigment route to the solution-based deposition of trans-quinacridone (QA) enables well-intermixed QA:PhO-Cl6BsubPc layers. Green-selective photodetectors with cutting-edge performance are thus realized, achieving a 25 % increase in external quantum efficiency compared to all prior solution-based NBA implementations, as well as a nearly five-fold enhancement of the green-to-blue spectral rejection ratio. The merit of this approach is further illustrated by comparison with the corresponding fullerene-based photodetectors. By demonstrating an approach to solution-based NBA photodetectors with cutting-edge photoconversion efficiency and spectral selectivity, this study represents an important step toward printable, high-performance organic color sensors and imagers.
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39

Cheng, Zhongming, Huichun Wu, Mingyang Yu, and Dachao Deng. "Relativistic toroidal light solitons in plasma." Plasma Science and Technology, November 11, 2022. http://dx.doi.org/10.1088/2058-6272/aca232.

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Abstract In laser plasma interaction, relativistic soliton formation is an interesting nonlinear phenomenon and important light mode convection in plasmas. Here, it is shown by three-dimensional particle-in-cell simulations that relativistic toroidal solitons, composed of intense light self-consistently trapped in toroidal plasma cavities, can be produced by azimuthally-polarized relativistic laser pulses in a near-critical underdense plasma.
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40

Rommel, Cédric, Joseph Paillard, Thomas Moreau, and Alexandre Gramfort. "Data augmentation for learning predictive models on EEG: a systematic comparison." Journal of Neural Engineering, November 11, 2022. http://dx.doi.org/10.1088/1741-2552/aca220.

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Abstract Objective: The use of deep learning for electroencephalography (EEG) classification tasks has been rapidly growing in the last years, yet its application has been limited by the relatively small size of EEG datasets. Data augmentation, which consists in artificially increasing the size of the dataset during training, can be employed to alleviate this problem. While a few augmentation transformations for EEG data have been proposed in the literature, their positive impact on performance is often evaluated on a single dataset and compared to one or two competing augmentation methods. This work proposes to better validate the existing data augmentation approaches through a unified and exhaustive analysis. Approach: We compare quantitatively 13 different augmentations with two different predictive tasks, datasets and models, using three different types of experiments. Main results: We demonstrate that employing the adequate data augmentations can bring up to 45% accuracy improvements in low data regimes compared to the same model trained without any augmentation. Our experiments also show that there is no single best augmentation strategy, as the good augmentations differ on each task. Significance: Our results highlight the best data augmentations to consider for sleep stage classification and motor imagery brain-computer interfaces. More broadly, it demonstrates that EEG classification tasks benefit from adequate data augmentation
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41

Lai, Tang-Yu. "Thermoelectric properties variation in antimony telluride nanofilm using molecular dynamics." Materials Research Express, November 11, 2022. http://dx.doi.org/10.1088/2053-1591/aca242.

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Abstract In recent years, thermoelectric materials that have the advantage of directly converting heat into electricity, have become a hot research topic. In this study, we designed a series of Sb2Te3 nanofilms using molecular dynamics simulation to explore the effects of structural defects on the phonon transport properties of thermoelectric materials. We predicted that temperature variations and structural defects can greatly increase the transfer of energy invalid and decrease thermal conductivity. Designing thermoelectric materials as composite interfaces, multilayer films, and defect structures is an effective way to achieve this goal.
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42

PARVIN, REAJMINA, Tushar Sarkar, Rakesh Kumar Singh, and Maruthi Manoj Brundavanam. "Aberration-insensitive twisted wavefront detection using polarization correlation." Journal of Optics, November 11, 2022. http://dx.doi.org/10.1088/2040-8986/aca212.

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Abstract We have demonstrated using higher-order Stokes correlations that the retrieved amplitude and phase information of the optical vortex (OV) beam and its orbital angular momentum (OAM) spectrum when it is propagating through a scattering medium are insensitive to the external aberration in the propagation channel. A theoretical framework of the proposed technique is described and validated by considering an aberration in the propagation channel. The usefulness of the technique is demonstrated in the recovery of amplitude and phase information of an OV beam even in presence of external aberration. Comparisons between aberrated and non-aberrated cases are discussed to examine and evaluate the performance of the technique.
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43

Ma, Ni, De-Yang Wang, Ben-Rui Huang, et al. "Quasi-one-dimensional characters in topological semimetal TaNiTe5." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca203.

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Abstract One-dimensional (1D) topological insulators are superior for low-dissipation applications owing to the 1D character of surface states where scatterings other than prohibited backscattering are further restricted. Among the proposed candidates for 1D topological materials, TaNiTe5 has attracted intensive attention for its quasi-one-dimensional (quasi-1D) crystalline structure. In this study, we identified the chain-like construction and anisotropic electronic states on TaNiTe5 surface with scanning tunneling microscopy. The electron scatterings are largely suppressed even with chromium impurities deposited on the surface and magnetic field applied normal to the surface, which endows TaNiTe5 great potential for low-dissipation spintronic applications.
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44

Wang, Yinshun, Wang Jian, Wei Liu, Jiawen Wang, Ziqing Meng, and Wei Pi. "Dependence of dynamic resistances in HTS quasi-isotropic strand on magnitude and orientation of AC magnetic field." Superconductor Science and Technology, November 11, 2022. http://dx.doi.org/10.1088/1361-6668/aca224.

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Abstract Dynamic resistance of superconductor appears if it carries DC current and is simultaneously exposed to AC magnetic fields if their amplitude is higher than its full penetrated field. Due to its strong anisotropy, dynamic resistance of HTS tape is not only affected by magnitude of AC magnetic fields but also their orientations. Particularly, the dynamic resistance has considerable effect on current distribution in HTS cables (except for Roebel cable) or even CICC made from those HTS cables except of dissipative loss. This paper presents behavior of dynamic resistance in high temperature superconducting (HTS) Quasi-isotropic strand (Q-IS), which consists of four sub-stacked 2G HTS tapes proposed by our group in North China Electric Power University (NCEPU) while it carries DC current and simultaneously experiences an AC magnetic field with different magnitudes and orientations. A angular dpendence of dynamic rsistance in a single 2G HTS tape in AC magnetic field with various orientatons is firstly performed in simulation and experiment, respectively. The experimental results are good agreement with the simulated ones, which shows that the dynamic resistance of a Q-IS exhibits also quasi-isotropic characteristics and has important effect on distribution of DC transport current. The related results are promising for designs and applications of other DC HTS cables, feeders or magnet.
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45

Sun, H. Hohyun, Glenn R. Pastel, Sheng S. Zhang, Dat T. Tran, and Jan L. Allen. "Structural Optimization of Al-Doped Li[Ni0.90Co0.05Mn0.05]O2 Cathode for Li-Ion Batteries." Journal of The Electrochemical Society, November 11, 2022. http://dx.doi.org/10.1149/1945-7111/aca223.

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Abstract Aluminum is a well-known dopant element as it is used in Li[Ni0.80Co0.15Al0.05]O2 but its optimized usage in Li[NixCoyMnz]O2 cathodes with x ≥ 0.90 has not been explored in depth. Here, we survey various Al-dopant concentrations (0.5, 1, 2, 3, and 5 mol%) to investigate the effect of Al-doping of highly Ni-rich layered Li[Ni0.90Co0.05Mn0.05]O2 cathode with respect to the electrochemical and structural properties. It is shown that Al is effective in enhancing the electrochemical performance of the Li[Ni0.90Co0.05Mn0.05]O2 cathode at higher than 1 mol% concentrations but becomes detrimental at 3 mol% or greater concentrations. In particular, Li[Ni0.90Co0.05Mn0.05]O2 with 2 mol% Al-doping delivers the most optimal electrochemical performance with 93% capacity retention over 100 cycles at 0.5 C within the 2.7–4.3 V voltage range as compared to the 85% retention of Li[Ni0.90Co0.05Mn0.05]O2 under the same conditions versus Li0/Li+ in half cells. Analyses of the ex-situ and in-situ X-ray diffraction patterns, cell impedances over 100 cycles, and cross-sectional electrode images reveal that appropriate amounts of Al in the layered structure alleviate the extent of unit cell volume changes during charge, but excessive Al-dopant addition leads to the formation of γ-LiAlO2 byproducts that consume available Li to significantly impair the efficacy of the cathode.
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46

Kaur, Hardeep, Vivek Anand, Ajay Sharma, et al. "Mechanistic Investigation of Formation of Highly-Dispersed Silver Nanoparticles using Sea buckthorn Extract." Nanotechnology, November 11, 2022. http://dx.doi.org/10.1088/1361-6528/aca20d.

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Abstract Nowadays, the greener pathways for the synthesis of nanostructures are being explored. The extracts of different parts of plants viz leaves, stems, and roots have been investigated. However, these extracts have been prepared by simply boiling or microwaving, or sonicating the parts of plants with water. Therefore, to have deeper insight and to investigate the full potential of plant extracts, serial extraction of leaves of Sea buckthorn (Hippophae rhamnoides L.) which is a medicinally important plant was attempted using the soxhlet apparatus. The as-obtained polyphenolic-rich extract was employed for the preparation of silver nanoparticles (Ag-NPs). Under optimized reaction conditions viz 60 oC temperature and 500 μL of extract solution (5 mg/mL) highly disperse spherical nanoparticles of the average size of 15.8 + 4.8 nm were obtained. Further, the optical band gap of Ag-NPs prepared using optimized reaction conditions was found to be 2.6 eV using the Tauc equation. Additionally, to understand the reduction by the extract, kinetic studies were also carried out which suggest the predominant occurrence of pseudo-first-order reaction. Furthermore, the mechanism of formation of Ag-NPs using major components of extract viz gallic acid and catechin which were identified by HPLC were also investigated using DFT. The mechanistic investigation was performed for both the keto-enol and radical-mediated preparation of Ag-NPs. Such theoretical investigations will help in the efficient designing of greener and novel routes for the synthesis of Ag-NPs. Additionally, the prepared silver was also employed for the colorimetric detection of H2O2.
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47

Shirai, Yusei, Hirokazu TATSUOKA, and Yosuke Shimura. "Ge1-xSnx nanodots crystal nuclei for solid phase crystallization of poly-Si1-x-yGexSny." Japanese Journal of Applied Physics, November 11, 2022. http://dx.doi.org/10.35848/1347-4065/aca20e.

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Abstract Solid phase crystallization of polycrystalline Si1-x-yGexSny using Ge1-xSnx nanodots (Ge1-xSnx-ND) as crystal nuclei was examined. The effects of the substrate temperature and the ratio of the deposited Ge and Sn on the dot size, the coverage, and the substitutional Sn content in the Ge1-xSnx-ND were investigated. Lowering deposition temperature increased the coverage and the substitutional Sn content of the Ge1-xSnx-ND. Crystallization of Si deposited on the Ge1-xSnx-ND was confirmed at the deposition temperature of 150 °C. The Si content was higher when Si was deposited on nanodots with higher coverage, and the Si and Sn contents in the poly-Si1-x-yGexSny layer were estimated as high as 36.3% and 4.2%, respectively, after annealing at 225 °C for 30 minutes.
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48

Ma, Teng, Jing 舒菁 Shu, and Ming Lei Xiao. "Standard Model Effective Field Theory from On-shell Amplitudes." Chinese Physics C, November 11, 2022. http://dx.doi.org/10.1088/1674-1137/aca200.

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Abstract We present a general method of constructing unfactorizable on-shell amplitudes (amplitude basis), and build up their one-to-one correspondence to the independent and complete operator basis in effective field theory (EFT). We apply our method to the Standard Model EFT, and identify the amplitude basis in dimension 5 and 6, which correspond to the Weinberg operator and operators in Warsaw basis except for some linear combinations. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
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49

Freire, Eduily Benvindo Vaz, Anderson Lira de Sales Santos, Giordano Frederico da Cunha Bispo, Zélia Soares Macedo, Robert A. Jackson, and Mário Ernesto Giroldo Valerio. "Effect of trivalent rare earth doping in cadmium silicates hosts: A theoretical study." Physica Scripta, November 11, 2022. http://dx.doi.org/10.1088/1402-4896/aca228.

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Abstract The objective of the present work is to investigate the possibilities for extrinsic defects in the three cadmium silicate matrices, CdSiO3, Cd2SiO4 and Cd3SiO5 and understand the final geometry of the most energetically favourable defects, which are generators of the luminescence centres in the material. This analysis will be performed out through classical and static computer modelling, using the code GULP. A number different mechanisms were modelled and their related solid state reactions were devised allowing the energetic calculations for the incorporation of trivalent rare earth ions(R3+) in these matrixes. The results demonstrated that the trivalent rare earth ions are preferentially incorporated substitutional at Cd sites with cadmium vacancy being created in order to compensate charge unbalance. Careful investigations of the different distances and angles between the ions involved in the defects formation for CdSiO3 found that all investigated R3+ ions have the same lower energetic defect configuration. The lowest energetic costs were found for a configuration where the rare earth ions and the accompanying vacancy are almost aligned with a distance of around 7Å and an angle closer to 180º. These results predict a possible set of two dipoles caused by the position of the cadmium vacancy in defect. Cadmium vacancies were expected to be present in the cadmium silicate due to the low vapor pressure of CdO; however, no previous work was able to pre-establish the final geometric structure of the cadmium silicate matrix in the defective region that can modify the luminescent centres in the material. The study of a wide range of possibilities for the insertion of defects and the proposal for the final configuration of these defects is presented, in order to assist in the identification of the sources and the specific chracteristics of the luminescent emissions presented in cadmium silicates doped with R3+.
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50

Zhang, Ningzhe, Xiaopeng Yan, Minghui Lv, Xiumei Chen, and Dingkun Huang. "Parameter estimation method for an LFM signal with a Duffing oscillator based on frequency periodicity." Chinese Physics B, November 11, 2022. http://dx.doi.org/10.1088/1674-1056/aca206.

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Abstract In view of the complexity of the existing linear frequency modulation (LFM) signal parameter estimation methods and the poor antinoise performance and estimation accuracy under a low signal-to-noise ratio (SNR), a parameter estimation method for LFM signals with a Duffing oscillator based on frequency periodicity is proposed in this paper. This method utilizes the characteristic that the output signal of the Duffing oscillator excited by the LFM signal changes periodically with frequency, and the modulation period of the LFM signal is estimated by autocorrelation processing of the output signal of the Duffing oscillator. On this basis, the corresponding relationship between the reference frequency of the frequency-aligned Duffing oscillator and the frequency range of the LFM signal is analyzed by the periodic power spectrum method, and then the frequency information of the LFM signal is determined. Simulation results show that this method can achieve high-accuracy parameter estimation for LFM signals at an SNR of -25 dB.
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