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Vibrational polaritons form in a planar Fabry–Pérot microcavity when a vibrational mode of a layer of molecules is near resonant with an infrared cavity mode. Here, dispersion relations of vibrational polaritons are studied when the molecular density distribution breaks the macroscopic translational symmetry along the cavity mirror plane. Both perturbative theory and numerical calculations show that, if a homogeneous in-plane molecular distribution is modulated by sinusoidal fluctuations, in addition to a pair of upper and lower polariton branches, a discrete number of side polariton branches may emerge in the polariton dispersion relation. Moreover, for a periodic Gaussian in-plane density distribution, only two, yet significantly broadened polariton branches exist in the spectra. This polariton linewidth broadening is caused by the scattering between cavity modes at neighboring in-plane frequencies due to the symmetry breaking, which is distinguished from known origins of polariton broadening such as the homogeneous broadening of molecules, the cavity loss, or the large energetic disorder of molecules. Associated with the broadened polariton branches, under the periodic Gaussian in-plane inhomogeneity, a significant number of the vibrational strong coupling eigenstates contain a non-zero contribution from the cavity photon mode at zero in-plane frequency, blurring the distinction between the bright and the dark modes. Looking forward, our theoretical investigation should facilitate the experimental exploration of vibrational polaritons with patterned in-plane molecular density distributions. [ABSTRACT FROM AUTHOR]

Modeling the behavior of a prototype cantilevered X-ray adaptive mirror (held from one end) demonstrates its potential for use on high-performance X-ray beamlines. Similar adaptive mirrors are used on X-ray beamlines to compensate optical aberrations, control wavefronts and tune mirror focal distances at will. Controlled by 1D arrays of piezoceramic actuators, these glancing-incidence mirrors can provide nanometre-scale surface shape adjustment capabilities. However, significant engineering challenges remain for mounting them with low distortion and low environmental sensitivity. Finite-element analysis is used to predict the micron-scale full actuation surface shape from each channel and then linear modeling is applied to investigate the mirrors' ability to reach target profiles. Using either uniform or arbitrary spatial weighting, actuator voltages are optimized using a Moore-Penrose matrix inverse, or pseudoinverse, revealing a spatial dependence on the shape fitting with increasing fidelity farther from the mount.

Whether visuomotor plasticity of postural control is a trainable feature in older age remains an open question despite the wealth of visually guided exercise games promising to improve balance skill. We asked how aging affects adaptation and learning of a visual feedback (VF) reversal during visually guided weight shifting and whether this skill is modulated by explicit knowledge. Twenty-four older (71.43 + 2.54 years) and 24 young (24.04 1 0.93 years) participants were exposed to a 180° VF reversal while tracking a horizontally moving target by voluntarily weight shifting between two force platforms. An explicit strategy was available to half of the participants with detailed instruction to counter the VF rotation. Individual error data were fitted to an exponential function to assess adaptation. Fewer older (12/24) than younger (21/24) participants adapted to the VF reversal, displaying error curves that fitted the exponential function. Older adults who adapted to the VF reversal (responders. n= 12) reached an asymptote in performance in the same weight shifting cycle and displayed a similar mean asymptotic error compared with young participants. Young but not older responders exhibited an aftereffect when the VF reversal was removed. Instruction did not influence spatial error modulations regardless of age. The large individual variations within the older adults' group during early adaptation suggest age-specific limitations in using explicit cognitive strategies when older adults are exposed to an abrupt mirror feedback reversal that requires a change in weight shifting direction during whole-body postural tracking. [ABSTRACT FROM AUTHOR]

Aiming at the interferences caused by vibrations on the target monitoring system of satellite platforms, an experimental system of optical–mechanical–electrical joint image stabilization based on inertial sensors and piezoelectric fast mirrors was studied. First of all, the data from the fiber optic gyroscope and the detector are combined and processed. After that, the predicted intentional velocity is subtracted from the real-time gyroscope data, and the vibration displacement is obtained using an integral. The feedback amount is calculated using the processor according to the vibration displacement, the piezoelectric fast mirror is controlled to compensate the vibration interferences, and the purpose of stabilizing the images is achieved. The experimental results show that under a vibration interference of 300 μ rad /s, the image stabilization control frequency of the system reaches 500 Hz, the relative error between image frames is better than 3 μ rad , and the intra-frame stabilization performance of the detector meets the requirements on stabilized image and target detection for space targets on the star-carrying platform. [ABSTRACT FROM AUTHOR]

A non-destructive method for detecting sub-micrometer-sized micropipes on an entire wafer surface is investigated. Since it is difficult to detect sub-micrometer-sized micropipes due to their small core size, a non-destructively and accurately detecting method is required. To solve the issue, we focus on a characteristic depression generated around micropipes, namely, line-shaped depressions. In this paper, the location of line-shaped depressions is identified by using optical inspection, and the line-shaped depressions are distinguished whether micropipes exhibit line-shaped depression or not by using mirror electron microscope observation as high-resolution inspection. The accuracy of the distinction results is confirmed by scanning electron microscope observation, and electrical characteristics of the P–N diode are fabricated using the inspected wafer. Furthermore, the sub-micrometer-sized micropipes are observed at the sites of leakage current identified by emission microscopy. Additionally, device simulation of the blocking-voltage characteristics of P–N diodes suggests that the increase in leakage current depends on the electric field at the sub-micrometer-sized micropipes, regardless of their core size. [ABSTRACT FROM AUTHOR]

This phenomenological study aimed to provide an in-depth understanding to answer the question of how participants described their views, and feelings and how it affected their lives in teaching learners with disability in limited face-to-face learning. The 10 SPED teachers served as the respondents of the study. Given the restricted participant pool, purposive sampling was employed. Five (5) SPED teachers for the individual in-depth interview (IDI), and five (5) for the focus group discussion (FGD) from General Santos City SPED Integrated School. The Qualitative Research Method using the validated Semi-Structured Interview Guide to gather data from the participants, and thematic analysis was applied to interpret the data. Based on the findings of the study these significant themes emerged their experiences: full of adjustment, dealing with diverse behaviour, providing guidance, showing consideration, discovering the learner's situation, and attending to learners' needs. Moreover, their coping mechanism the themes were: happy to teach, fulfilled to help learners, challenged, and exhausted. Finally, for insights the themes were privileged with educational training, employed collaboration, provided quality learning, and postered positivism. The results of the study revealed that SPED teachers were happy and enthusiastic to teach learners in the limited face-toface learning, nevertheless, the challenges of monitoring and assessing students' learning, progress, and behavior were primary factors to address in class. Hence, SPED teachers needed coping mechanisms to with the circumstances in class. [ABSTRACT FROM AUTHOR]

ABSTRACT Aims Background Design Methods Results Conclusion Impact Reporting Method Patient or Public Contribution To uncover the mirror‐viewing experience in African‐American (AA) women with obesity.Obesity is among the most preventable healthcare epidemics and is linked to multiple health problems. Unfortunately, AA women are disproportionately affected by obesity. Mirror exposure has exclusively used mirrors to treat various eating disorders such as anorexia nervosa, bulimia nervosa and binge eating. Participants in prior mirror exposure studies reported increased self‐esteem, body image acceptance, behaviour modification, decreased weight and body shape concerns and lower rates of depression.This qualitative study used hermeneutic phenomenology to explore and methodically analyse participants' experiences.Thirteen AA women who self‐identified as having obesity were interviewed. A phenomenological hermeneutical approach was used to explore their mirror‐viewing experience.Two environmental themes surrounding this phenomenon were (1) family and culture and (2) stereotype/stigma and bias. Five phenomenological themes were identified: (1) I do not like what I see, (2) the struggle is real, (3) camouflage, (4) call for action and (5) loving the skin you are in.African‐American women grappling with obesity confront emotional and body image challenges compounded by family, culture, bias and a sense of alienation within society. The mirror, for many, is an everyday tool that becomes a call for action. Despite earnest attempts to pursue a healthier weight, many find it daunting. Additional investigation into sensitive mirror intervention studies specific to this demographic is warranted to address these multifaceted issues better.The knowledge gained from the study offers an understanding of the mirror‐viewing experience in AA women with obesity.Standards for Reporting Qualitative Research.No patient or public contribution. [ABSTRACT FROM AUTHOR]

This paper presents a design of fully differential chopper amplifier employing the flipped voltage follower (FVF) adaptive biasing technique, focusing on its potential use in biopotential recording applications. The suggested architectural OTA incorporates self-cascoded current mirrors (SCCMs) as the active load to achieve a substantial output swing. The FVFs based adaptive biasing approach for the differential input stage boosts extra current and enhances gain and dynamic characteristics. The chopper amplifier attains a common mode rejection ratio (CMRR) of more than 100 dB through the strategic utilization of chopper modulators and pseudo-resistors. Additionally, this device exhibits characteristics such as accurate and stable gain, high input impedance, and a compact physical footprint. The present study also includes a comparison between the suggested structure and the bio-potential amplifiers discussed in the existing literature. This comparison is based on key metrics such as gain, input referred noise (IRN), CMRR, and input impedance (Zin). The proposed structure yielded a gain of 63.72 dB, an IRN of 0.07nVrms, a CMRR of 127.97 dB and a Zin of 1.54 GΩ. The bio-potential chopper amplifier under consideration was constructed and simulations were performed by utilizing the Cadence Virtuoso Spectre simulator tool at 180 nm CMOS technology node. [ABSTRACT FROM AUTHOR]

Traffic network design is a pivotal aspect of urban planning, necessitating a harmonious blend of theoretical and practical approaches. In this paper, we propose a novel network design methodology utilizing Delaunay triangulation. We address the limitations of raw Delaunay networks, particularly their triangular configurations, by introducing edge-reduction techniques guided by a newly developed metric, detour redundancy. This metric is instrumental in assessing edge importance, facilitating the transformation of the network to better mirror real-world traffic scenarios. The efficacy and practical application of the designed networks are then evaluated through traffic simulations using the principles of cellular automata. Our findings underscore the potential of this approach in enriching traffic network design and pave the way for future investigations into diverse network characteristics and their implications in urban environments. [ABSTRACT FROM AUTHOR]

In this study, we developed a new method for designing progressive addition-multifocus defocused freeform lenses. We used two independent meridians and achieved a smooth gradient transition of additional optical power from the center to the peripheral area of the lens, along with an asymmetric distribution of additional optical power on the nasal-temporal side of the lens. To improve the optical performance of the lenses, we developed three different designs based on the distribution of the additional optical power on the meridians. We conducted simulations and processing on the three different designs. The lenses designed using improved logistic regression and sine functions for meridian optical power distribution exhibited stable optical performance in the central focus area. They also met the design requirements for additional optical power. However, significant distortion was still observed in the peripheral region, which required further optimization. Lenses designed using piecewise linear functions for meridian optical power distribution exhibited relatively poor optical performance with significant optimization potential. Thus, combining the optical power distribution and surface-type factors for optimization is necessary. The proposed method enabled designing of defocus-free curved mirror lenses that satisfy the optical performance requirements. Thus, this method provides a new approach for the design of progressive addition lenses. [ABSTRACT FROM AUTHOR]

This work investigates a Bregman and inertial extension of the forward–reflected–backward algorithm (Malitsky and Tam in SIAM J Optim 30:1451–1472, 2020) applied to structured nonconvex minimization problems under relative smoothness. To this end, the proposed algorithm hinges on two key features: taking inertial steps in the dual space, and allowing for possibly negative inertial values. The interpretation of relative smoothness as a two-sided weak convexity condition proves beneficial in providing tighter stepsize ranges. Our analysis begins with studying an envelope function associated with the algorithm that takes inertial terms into account through a novel product space formulation. Such construction substantially differs from similar objects in the literature and could offer new insights for extensions of splitting algorithms. Global convergence and rates are obtained by appealing to the Kurdyka–Łojasiewicz property. [ABSTRACT FROM AUTHOR]

The degradation of an AlGaN‐based deep‐ultraviolet laser diode during operation is studied. A rapid increase in threshold current without any facet mirror damage under direct current stress below the threshold current is observed, which is considered to limit the lifetime of continuous wave lasing to the level of seconds. The evolution of current–light and current–voltage characteristics suggests that the dominant mechanism of degradation is the increased loss of carriers before they can reach the active layer, i.e., the decrease in carrier injection efficiency. The decrease in emission intensity, which is more pronounced at lower current densities, and subsequent increase in sub‐threshold current indicate the increase in defect density under current stress, which is similar to the well‐analyzed degradation mechanism found in AlGaN‐based light‐emitting diodes. [ABSTRACT FROM AUTHOR]

In non-Hermitian open quantum systems, such as polariton condensates, the local tailoring of gains and losses opens up an interesting possibility to realize functional optical elements. Here, we demonstrate that deliberately introducing losses via a photonic defect, realized by reducing the quality factor of a DBR mirror locally within an ultrahigh-quality microcavity, may be utilized to create directed polariton currents towards the defect. We discuss the role of polariton–polariton interactions in the process and how to tailor the effective decay time of a polariton condensate by coupling it to the defect. Our results highlight the far-reaching potential of non-Hermitian physics in polaritonics. [ABSTRACT FROM AUTHOR]

For a log Calabi Yau pair (X,D$X,D$) with X∖D$X\setminus D$ smooth affine, satisfying either a maximal degeneracy assumption or contains a Zariski dense torus, we prove under the condition that D is the support of a nef divisor that the structure constants defining a trace form on the mirror algebra constructed by Gross–Siebert are given by the naive curve counts defined by Keel–Yu. As a corollary, we deduce that the equality of the mirror algebras constructed by Gross–Siebert and Keel–Yu in the case X∖D$X\setminus D$ contains a Zariski dense torus. In addition, we use this result to prove a mirror conjecture proposed by Mandel for Fano pairs satisfying the maximal degeneracy assumption. [ABSTRACT FROM AUTHOR]

Mirror symmetry for higher genus curves is usually formulated and studied in terms of Landau–Ginzburg models; however the critical locus of the superpotential is arguably of greater intrinsic relevance to mirror symmetry than the whole Landau–Ginzburg model. Accordingly, we propose a new approach to the A-model of the mirror, viewed as a trivalent configuration of rational curves together with some extra data at the nodal points. In this context, we introduce a version of Lagrangian Floer theory and the Fukaya category for trivalent graphs, and show that homological mirror symmetry holds, namely, that the Fukaya category of a trivalent configuration of rational curves is equivalent to the derived category of a non-Archimedean generalized Tate curve. To illustrate the concrete nature of this equivalence, we show how explicit formulas for theta functions and for the canonical map of the curve arise naturally under mirror symmetry. [ABSTRACT FROM AUTHOR]

1T-CrTe2 is one of the typical two-dimensional transition metal dichalcogenides (TMDCs) and has attracted great attention in the field of spintronics due to its fascinating magnetic properties. However, the optical properties such as the nonlinear optical characteristics of 1T-CrTe2 films have rarely been reported. Here, the CrTe2 thin films were prepared on highly oriented pyrolytic graphite and gold-coated plane mirrors via molecular beam epitaxy. By adjusting the growth temperature and the flux of the source, CrTe2 thin films with various morphologies were obtained. In addition, the CrTe2 thin films were used as saturable absorbers (SAs) and incorporated into Er-doped fiber lasers. A modulation depth of 43.5% and mode-locking at 1560 nm with a pulse width of 316 fs were achieved, showing extremely outstanding nonlinear optical response among TMDCs. This work demonstrates the growth of high-quality CrTe2 films and verifies that CrTe2 films have enormous prospects in ultrafast optical devices. [ABSTRACT FROM AUTHOR]

AbstractOnline interactions have become an essential but understudied aspect of our social lives. The current research investigates self-view in video-based interactions, a key difference from face-to-face interactions. Using computer vision techniques for automated gaze analysis, we assessed the relative frequency with which individuals in online interactions gaze at themselves and investigated its links to personality characteristics. We hypothesized that self-referent gaze frequency may indicate participants’ public and private self-awareness and explored correlations with the Big Five and narcissism. We included trait and state measures from self- and other-reports. Surprisingly, self-referent gaze was not reliably related to these variables. We discuss the relevance of these findings for challenging common beliefs about the diagnostic value of self-referent gaze behavior in online interactions. [ABSTRACT FROM AUTHOR]

Quantum cascade lasers (QCLs) in the mid-infrared (MIR) hold significant potential for widespread applications in both military and civilian contexts. However, the utility of present single-chip QCLs is hampered by issues such as low output power and subpar beam quality. This study addresses these limitations by employing spectral beam combining (SBC) based on a diffraction grating, with an aim to enhance both power and beam quality of MIR QCLs. Coaxial power synthesis of three single-chip QCLs (around 4.75 μm) is achieved experimentally, importantly, the beam quality did not decrease after combining, essentially maintaining the same quality as before combining. It is proposed that there are four main factors affecting the combining efficiency, namely operating optical power (or driving current) of the chips, individual differences in QCL chips, diffraction grating, and reflectivity of feedback mirror, and their effects on the combining efficiency are discussed separately. This study confirms that SBC is an effective way to obtain high-power and high-beam quality MIR QCL sources, and lays a research foundation for more beam spectral combining. [ABSTRACT FROM AUTHOR]

Allokotosauria (Trilophosauridae + Azendohsauridae) is a clade of Early – Late Triassic quadruped, sprawling archosauromorphs with diverse dietary habits, known from Madagascar, India, Morocco, North America, and Europe. We conducted the first quantitative biogeographic analysis of the clade to reconstruct its ancestral areas and dispersal events. The results estimated the India + Tanzania area as ancestral for Allokotosauria. Eastern North America was reconstructed as the ancestral area of Trilophosauridae, implying an Early Triassic Southern to Northern Hemisphere dispersal. Subsequently, trilophosaurids were restricted to the Northern Hemisphere, and at least two dispersal events from Europe to western North America are estimated during the early Anisian and probably during the early Carnian, respectively. Azendohsauridae retained the ancestral area of India + Tanzania during much of its evolutionary history. Two dispersal events to western and eastern North America, respectively, are reconstructed during the Carnian – early Norian, likely during or in the aftermath of the Carnian Pluvial Episode (CPE). This pattern mirrors that of early dinosaurs, which were restricted to the Southern Hemisphere with dispersals to the Northern Hemisphere not recorded until the end of the CPE. This study informs about biogeographic patterns involved in the biotic recovery after the end-Permian mass extinction and the early evolutionary radiation of Archosauromorpha. [ABSTRACT FROM AUTHOR]

The article analyzes moralizing voyeurism in the work "El día de fiesta en Madrid y sucesos que en él pasan" by Juan de Zabaleta. It details how the author describes the festivities and characters of Madrid, combining customs with moral advice. The text focuses on the structure and rhetoric of the work, highlighting the use of visual motifs such as mirrors and portraits. The importance of the reader as a collaborator in the transmission of the author's reformist objectives is emphasized. [Extracted from the article]

Zhou et al. (2022) proposed a method for instantaneous source depth estimation in deep water using matched beam intensity processing (MBIP) that leverages depth‐related oscillatory features arising from Lloyd's mirror interference in the frequency domain (Appl. Acoust., 2022, 186, 108493). However, the efficacy of MBIP diminishes with a random source spectrum. To counteract the effect of a random source spectrum, a vertical line array (VLA) positioned near the sea bottom is employed and a cross‐spectrum is generated from the conventional beamforming output, which is achieved by dividing the VLA into upper‐half and lower‐half arrays. The authors find that the cross‐spectrum phase interference pattern is determined by the source depth and is unaffected by the source spectrum. Consequently, a matched cross‐spectrum phase processing method is proposed, which demonstrates appreciable depth estimation accuracy compared to that of the existing techniques, as evidenced by the results from both simulated and experimental data. [ABSTRACT FROM AUTHOR]

Replacing the endocentric lenses in traditional Phase-Measuring Deflectometry (PMD) with bi-telecentric lenses can reduce the number of parameters to be optimized during the calibration process, which can effectively increase both measurement precision and efficiency. Consequently, the low distortion characteristics of bi-telecentric PMD contribute to improved measurement accuracy. However, the calibration of the extrinsic parameters of bi-telecentric lenses requires the help of a micro-positioning stage. Using a micro-positioning stage for the calibration of external parameters can result in an excessively cumbersome and time-consuming calibration process. Thus, this study proposes a holistic and flexible calibration solution for which only one flat mirror in three poses is needed. In order to obtain accurate measurement results, the calibration residuals are utilized to construct the inverse distortion map through bicubic Hermite interpolation in order to obtain accurate anchor positioning result. The calibrated stereo bi-telecentric PMD can achieve 3.5 μm (Peak-to-Valley value) accuracy within 100 mm (Width) × 100 mm (Height) × 200 mm (Depth) domain for various surfaces. This allows the obtaining of reliable measurement results without restricting the placement of the surface under test. [ABSTRACT FROM AUTHOR]

The water consumption rate for hydropower station power generation is an important index of the economic operation of hydropower stations, which has been widely considered and applied in the production practice of hydropower stations and has great significance for the full utilization of hydroelectric resources. This paper takes A and B cascade hydropower stations as the research objects to study the variation patterns of the water consumption rate of hydropower stations under different conditions, which mainly includes the following: (1) in this study, the relationship curve of output–gross head–flow (NHgrossQ) of each unit was established based on the relationship curve of output–net head–flow (NHQ) and the flow–head loss curve of each unit; (2) the mirror vertical shift method was used to calculate and plot the relationship curve of gross head–flow for combinations of multiple units; (3) the outflow–water–output characteristic curve of the hydropower station under the conditions of different reservoir water levels, different discharge flow, or different power generation output under the optimal operation of the hydropower station were calculated and drawn; (4) the outflow–water level–output curve of the hydropower station under various conditions was converted into an outflow–water level–water consumption curve; (5) the variation characteristics of the water consumption rate of the hydropower station under different conditions were analyzed; (6) on the basis of the definition of the water consumption rate of cascade hydropower stations, the research on the variation in the water consumption rate of cascade hydropower stations was carried out under the conditions of different water levels of the A reservoir, different water levels of the B reservoir, different discharge, and different total output of the hydropower stations. The variation pattern of the water consumption rate of hydropower stations under different conditions obtained in this paper can provide technical support for the real-time economic operation of cascade hydropower stations. [ABSTRACT FROM AUTHOR]

The influence of Si interlayers on the microstructure of the films and boundaries and on the reflective characteristics of Ti/Ni multilayer mirrors has been studied using X‐ray reflectometry and diffractometry. We established that these Si interlayers perform different functions at different interfaces. An Si interlayer at an Ni‐on‐Ti interface acts as a diffusion barrier. An Si interlayer at a Ti‐on‐Ni interface mainly acts as a smoothing layer with a slight diffusion barrier effect. The largest increase in the reflectance, from 62 to 65.7%, at a wavelength of 1.54 Å, is observed when Si interlayers are deposited on both boundaries. The reason for the increase in reflectivity is the decrease in the widths of the transition layers from 6.5 Å on Ni and 7.5 Å on Ti, to 6.0 Å on Ni and 5.0 Å on Ti, respectively. Here, we explain this through the 'barrier' effect of Si interlayers, which results in less mixing of film materials at the interfaces. Data on the reflectance of Ni/Ti multilayer mirrors in the spectral range of the 'water window' at a wavelength of 27.4 Å are presented for the first time. The maximum reflectivity for an Ni/Ti multilayer mirror at a grazing angle of 7.2° was about 56%. [ABSTRACT FROM AUTHOR]

Consider an infinite collection of particles on the real line moving according to independent Brownian motions and such that the i-th particle from the left gets the drift g i - 1 . The case where g 0 = 1 and g i = 0 for all i ∈ N corresponds to the well studied infinite Atlas model. Under conditions on the drift vector g = (g 0 , g 1 , ...) ′ it is known that the Markov process corresponding to the gap sequence of the associated ranked particles has a continuum of product form stationary distributions { π a g , a ∈ S g } where S g is a semi-infinite interval of the real line. In this work we show that all of these stationary distributions are extremal and ergodic. We also prove that any product form stationary distribution of this Markov process that satisfies a mild integrability condition must be π a g for some a ∈ S g . These results are new even for the infinite Atlas model. The work makes progress on the open problem of characterizing all the invariant distributions of general competing Brownian particle systems interacting through their relative ranks. Proofs rely on synchronous and mirror coupling of Brownian particles and properties of the intersection local times of the various particles in the infinite system. [ABSTRACT FROM AUTHOR]

Stimulated Brillouin scattering (SBS) is an effective method for compensating wavefront aberrations in high-energy lasers due to its phase conjugation property. However, SBS phase conjugate mirrors (SBS-PCMs) under high-power pumping often suffer from significant spatial aberrations and decreased energy reflectivity, indicating instability in the nonlinear gain. Here, a nonlinear gain modulation method is proposed to realize the stable output. Experiments show that the energy reflectivity of SBS decreased due to the thermal effect in high-repetition-rate pumped SBS-PCMs. The nonlinear gain modulation was accomplished with simultaneous adaptation of radial and axial focusing parameters resulting in a higher SBS gain under short-focus conditions. The feasibility of the method was experimentally confirmed by obtaining SBS energy reflectivity stabilized at 60%, while the root mean squares of steady-state Stokes energy and pulse time delay enhanced to 1.97% and 1.81%, respectively, in an HT-230 medium. This scheme ensures stable and efficient SBS output under high-power pumping, which is of great significance for expanding the application of SBS-PCMs in high-repetition-rate laser systems. [ABSTRACT FROM AUTHOR]

[Objective] Under the background of new engineering disciplines, the experimental teaching of mechanical dynamics combined with frontier technology plays an important role in promoting students' engineering practice and multidisciplinary integrating innovation abilities. To realize the combination of MEMS micromirror technology and mechanical dynamics teaching practice and achieve the purpose of design verification and parameter identification of MEMS micromirror, this study relies on a Huawei-funded project to conduct experiments on the amplitude--frequency characteristics of the MEMS micromirror. [Methods] Based on the working principle, the second-order dynamic equation of MEMS micromirror is established, and the MEMS micromirror is considered a typical second-order forced vibration problem. Therefore, its amplitude--frequency characteristics exhibit the resonance phenomenon; that is, when the driving frequency is the same as the natural frequency of the system, the angular amplitude of the micromirror reaches its maximum value. Students understand the theoretical knowledge of forced vibration combined with the experiment and use the knowledge to analyze and design the micromirror, which can promote the students' engineering practice ability. The MEMS micromirror amplitude--frequency experimental platform mainly includes an electromagnetically driven micromirror, laser source, photodetector, and signal processing board. The photodetector is realized by integrating a photodiode and a Gaussian light source. The light emitted by the Gaussian light source is reflected by the mirror attached to the back of the micromirror to the photodiodes, which are integrated with the light source into the same board. Then, the photodiodes generate an electric current through the photoelectric effect. The photodiode current passes through signal processing modules, such as amplification, low-pass filtering, and analog-to-digital conversion, to generate the output signals. When the MEMS micromirror is twisted, the light spot covering the photodiodes will be offset, resulting in the varying light intensities received by the two groups of photodiodes. As a result, the output signals corresponding to the two groups of photodiodes vary, and angle detection can be realized by calculating the difference of the output signals. The amplitude--frequency characteristic curve of the micromirror can be obtained by collecting the torsional amplitudes corresponding to different driving current frequencies. [Results] The experiment on the amplitude--frequency characteristics of the micromirror realized the precise identification of the natural frequency and quality factors of the micromirror, which lays the foundation for the formulation of the control scheme. The photodetector has the advantages of compact space and lightweight; thus, it can realize high integration with the MEMS micromirror, which has important engineering value for the product of the laser scanner. [Conclusions] The application of micromirror amplitude--frequency characteristic experiments in mechanical dynamics teaching enhances students' knowledge of engineering practice and multidisciplinary integrating innovation abilities, broadens students' understanding of frontier technologies and enhances students' desire to engage in scientific research work in the future. At the same time, Huawei's courage to break through the blockade inspired students' patriotism and craftsmanship, which had a significant effect on ideological and political lessons. [ABSTRACT FROM AUTHOR]

Fast steering mirrors (FSMs) designed by the micro-electro-mechanical system (MEMS) technology are significantly smaller in volume and mass, offering distinct advantages. To improve their performance in the open-loop control mode, this study introduces a control algorithm and evaluates its performance on an electromagnetic-driven MEMS-FSM. The algorithm employs a method to shape the input signal by fitting the system's transfer function and modifying the step response. This shaped signal is then applied to the system to minimize overshoot, reduce settling time, and improve working bandwidth, thereby enabling faster angular adjustments and improving the stability of the FSM. The experimental results demonstrate an 85.65% reduction in overshoot and a decrease in settling time from 84 ms to 0.4 ms. Consequently, the working bandwidth of the FSM system increases to 2500 Hz, demonstrating the effectiveness of the algorithm in enhancing MEMS-FSM's performance. [ABSTRACT FROM AUTHOR]

The effects of leader narcissism have sparked multiple controversies for decades, yet studies point out leader narcissism is generally regarded as a strong inhibitor of follower voice. However, this focus may overlook the potential role of follower narcissism in repairing the systems and relationships narcissistic leaders damaged. Building on approach-inhibition theory of power and literature on narcissism, we posit that the outcomes of leader narcissism may depend on the critical boundary condition of follower narcissism. Through a dyadic approach to consider leader and follower narcissism simultaneously, we explore whether and how leader-follower narcissism (in)congruence influences follower voice. Across a two-wave multi-phase and multi-source field study, the results of polynomial regression analyses showed that when leader and follower were congruent in narcissism, followers experienced a higher level of sense of psychological power. Compared to low-low dyadic congruence, follower sense of psychological power was higher in high-high dyadic congruence. Moreover, the asymmetric incongruence effects revealed that followers experienced the lowest level of sense of psychological power in the high-low dyadic incongruence. Meanwhile, sense of psychological power mediated the influence of leader-follower narcissism (in)congruence on follower voice. Theoretical and practical implications are also discussed. [ABSTRACT FROM AUTHOR]

This paper proposes a method for an automatic detection of 3D-display-friendly scenes from video sequences. Manual selection of such scenes by a human user would be extremely time consuming and would require additional evaluation of the result on 3D display. The input videos can be intentionally captured or taken from other sources, such as films. First, the input video is analyzed and the camera trajectory is estimated. The optimal frame sequence that follows defined rules, based on optical attributes of the display, is then extracted. This ensures the best visual quality and viewing comfort. The following identification of a correct focusing distance is an important step to produce a sharp and artifact-free result on a 3D display. Two novel and equally efficient focus metrics for 3D displays are proposed and evaluated. Further scene enhancements are proposed to correct the unsuitably captured video. Multiple image analysis approaches used in the proposal are compared in terms of both quality and time performance. The proposal is experimentally evaluated on a state-of-the-art 3D display by Looking Glass Factory and is suitable even for other multi-view devices. The problem of optimal scene detection, which includes the input frames extraction, resampling, and focusing, was not addressed in any previous research. Separate stages of the proposal were compared with existing methods, but the results show that the proposed scheme is optimal and cannot be replaced by other state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

In this paper, piezoelectric phononic crystals made up of interdigitated combs in floating potential condition are studied. Calculation of the dispersion curves shows that, in addition to Bragg bandgaps due to the presence of periodic electrodes, supplementary bandgaps are present corresponding to electrical resonance/antiresonance of the comb pairs. Calculation of the reflection coefficient of finite-sized mirrors reveals the presence of high amplitude reflection coefficient lobes near these bandgap frequencies. The electrical response of single port resonators using these interdigitated comb mirrors fabricated with Al metallization on LiTaO3 POI substrate is contrasted with that of a resonator with classical mirrors, providing experimental verification of this mechanism for bandgap opening. Possible applications for SAW device design are finally discussed. [ABSTRACT FROM AUTHOR]

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We report the results of laboratory studies of the main optical properties of the slitless spectrograph developed for a small telescope with a 0.5 m-diameter primary mirror and a focal ratio of . The spectrograph operates in the 450–950 nm wavelength interval and has a field of . Its distinctive feature is the use of a composite grism subdivided into two subapertures with independently optimized parameters. Measurements show that the use of such a grism makes it possible to achieve a spectral resolving power from 461 to 1041 with the grating diffraction efficiency as high as 45 . We demonstrate that our solution provides better optical characteristics compared to the classical grism and that our measurements agree well with the results of modeling. [ABSTRACT FROM AUTHOR]

While Bayesian methodology is increasingly favored in behavioral research for its clear probabilistic inference and model structure, its widespread acceptance as a standard meta-analysis approach remains limited. Although some conventional Bayesian hierarchical models are frequently used for analysis, their performance has not been thoroughly examined. This study evaluates two commonly used Bayesian models for meta-analysis of standardized mean difference and identifies significant issues with these models. In response, we introduce a new Bayesian model equipped with novel features that address existing model concerns and a broader limitation of the current Bayesian meta-analysis. Furthermore, we introduce a simple computational approach to construct simultaneous credible intervals for the summary effect and between-study heterogeneity, based on their joint posterior samples. This fully captures the joint uncertainty in these parameters, a task that is challenging or impractical with frequentist models. Through simulation studies rooted in a joint Bayesian/frequentist paradigm, we compare our model's performance against existing ones under conditions that mirror realistic research scenarios. The results reveal that our new model outperforms others and shows enhanced statistical properties. We also demonstrate the practicality of our models using real-world examples, highlighting how our approach strengthens the robustness of inferences regarding the summary effect. [ABSTRACT FROM AUTHOR]

Implicit representations like neural radiance fields (NeRF) showed impressive results for photorealistic rendering of complex scenes with fine details. However, ideal or near‐perfectly specular reflecting objects such as mirrors, which are often encountered in various indoor scenes, impose ambiguities and inconsistencies in the representation of the re‐constructed scene leading to severe artifacts in the synthesized renderings. In this paper, we present a novel reflection tracing method tailored for the involved volume rendering within NeRF that takes these mirror‐like objects into account while avoiding the cost of straightforward but expensive extensions through standard path tracing. By explicitly modelling the reflection behaviour using physically plausible materials and estimating the reflected radiance with Monte‐Carlo methods within the volume rendering formulation, we derive efficient strategies for importance sampling and the transmittance computation along rays from only few samples. We show that our novel method enables the training of consistent representations of such challenging scenes and achieves superior results in comparison to previous state‐of‐the‐art approaches. [ABSTRACT FROM AUTHOR]

This article critically engages Christina Van Dyke's interpretation of 'annihilation' in Marguerite Porete's Mirror of Simple Souls. Van Dyke's interpretation – well in accord with the consensus line among Porete scholars – emphasizes the alienness of Porete's understanding of union with God, and so seemingly guts the challenge of Porete's text. In other words, if Porete is saying what Van Dyke takes her to be saying, it is no wonder that anyone would find her vision alien, her posited end of Christian life undesirable, and the challenge to attain it inert. In this article, I describe and defend an alternative reading of the Mirror , one that makes the goal of 'self-annihilation' surprisingly more palatable. [ABSTRACT FROM AUTHOR]

The primary goal during cancer removal surgery is to completely excise the malignant tumor. Because the color of the tumor and surrounding tissues is very similar, it is difficult to observe with the naked eye, posing a risk of damaging surrounding blood vessels during the tumor removal process. Therefore, fluorescence emission is induced using a fluorescent contrast agent, and color classification is monitored through camera imaging. LEDs must be irradiated to generate the fluorescent emission electromotive force. However, the power and beam width of the LED are insufficient to generate this force effectively, so the beam width and intensity must be increased to irradiate the entire lesion. Additionally, there should be no shaded areas in the beam irradiation range. This paper proposes a method to enhance the beam width and intensity while eliminating shadow areas. A total reflection beam mirror was used to increase beam width and intensity. However, when the beam width increased, a shadow area appeared at the edge, limiting irradiation of the entire lesion. To compensate for this shadow area, a concave lens was combined with the beam mirror, resulting in an increase in beam width and intensity by more than 1.42 times and 18.6 times, respectively. Consequently, the beam width reached 111.8°, and the beam power was 13.6 mW. The proposed method is expected to be useful for observing tumors through the induction of fluorescence emission during cancer removal surgery or for pathological examination in the pathology department. [ABSTRACT FROM AUTHOR]

Quantum entanglement is essential in performing many quantum information tasks. Here, we theoretically investigate the stationary entanglement between a Laguerre–Gaussian (LG) cavity field and a rotating end mirror in an LG-cavity optorotational system with a nonlinear cross-Kerr (CK) interaction and a degenerate optical parametric amplifier (OPA). We calculate the logarithmic negativity of the system to quantify the stationary entanglement. We examine the influence of various system parameters such as the cavity detuning, the strength of the nonlinear CK interaction, the parametric gain and phase of the OPA, the power of the input Gaussian laser, the topological charge of the LG-cavity field, the mass of the rotating end mirror, and the ambient temperature on the stationary entanglement. Under the combined effect of the nonlinear CK interaction and the OPA, we find that the stationary entanglement can be substantially enhanced at lower Gaussian laser powers, smaller topological charges of the LG-cavity field, and larger masses of the rotating end mirror. We show that the combination of the nonlinear CK interaction and the OPA can make the stationary entanglement more robust against the ambient temperature. [ABSTRACT FROM AUTHOR]

In the structure of the title salt, {[Ba(μ3-C3H2N3O2)2(μ-H2O)(H2O)]·H2O}n, the barium ion and all three oxygen atoms of the water molecules reside on a mirror plane. The hydrogen atoms of the bridging water and the solvate water molecules are arranged across a mirror plane whereas all atoms of the monodentate aqua ligand are situated on this mirror plane. The distorted ninefold coordination of the Ba ions is completed with four nitroso-, two carbonyl- and three aqua-O atoms at the distances of 2.763 (3)–2.961 (4) Å and it is best described as tricapped trigonal prism. The three-dimensional framework structure is formed by face-sharing of the trigonal prisms, via μ-nitroso- and μ-aqua-O atoms, and also by the bridging coordination of the anions via carbonyl-O atoms occupying two out of the three cap positions. The solvate water molecules populate the crystal channels and facilitate a set of four directional hydrogen bonds. The principal Ba–carbamoylcyanonitrosomethanido linkage reveals a rare example of the inherently polar binodal six- and three-coordinated bipartite topology (three-letter notation sit). It suggests that small resonance-stabilized cyanonitroso anions can be utilized as bridging ligands for the supramolecular synthesis of MOF solids. Such an outcome may be anticipated for a broader range of hard Lewis acidic alkaline earth metal ions, which perfectly match the coordination preferences of highly nucleophilic nitroso-O atoms. Thermal analysis reveals two-stage dehydration of the title compound (383 and 473 K) followed by decomposition with release of CO2, HCN and H2O at 558 K. [ABSTRACT FROM AUTHOR]

Addressing the demand for high stability of beamline instruments at the SHINE facility, a high stability mirror regulating mechanism has been developed for mirror adjustments. Active mass damping was adopted to attenuate pitch angle vibrations of mirrors caused by structural vibrations. An internal absolute velocity feedback was used to reduce the negative impact of spillover effects and to improve performance. The experiment was conducted on a prototype structure of a mirror regulating mechanism, and results showed that the vibration RMS of the pitch angle was effectively attenuated from 47 nrad to 27 nrad above 1 Hz. [ABSTRACT FROM AUTHOR]

Beamline BL08U1A is a soft X‐ray spectromicroscopy beamline at Shanghai Synchrotron Radiation Facility (SSRF) that exhibits the capabilities of high spatial resolution (30 nm) and high energy resolving power (over 104). As a first‐generation beamline of SSRF, owing to its continuous operation over the last ten years, an urgent upgrade of the equipment including the monochromator was deemed necessary. The upgrade work included the overall construction of the monochromator and replacement of the mirrors upstream and downstream of the monochromator. Based on its original skeleton, two elliptically cylinder mirrors were designed to focus the beam horizontally, which can increase the flux density by about three times on the exit slits. Meanwhile, the application of variable‐line‐space gratings in the monochromator demonstrates the dual functions of dispersing and focusing on the exit slits which can decrease abberations dramatically. After the upgrade of the main components of the beamline, the energy range is 180–2000 eV, the energy resolving power reaches 16333 @ 244 eV and 12730 @ 401 eV, and the photon flux measured in the experimental station is over 2.45 × 109 photons s−1 (E/ΔE = 6440 @ 244 eV). [ABSTRACT FROM AUTHOR]

Physics instructors have faced challenges in providing relevant and interesting content to students in distant courses during the COVID-19 pandemic. To address this, a study used the manual focusing feature of smartphone cameras to demonstrate the relative positions of images in mirror and lens setups. Videos of manual focus practices were recorded and shown to students during distant optics lessons. The videos were found to be effective in helping students understand the concepts of image formation and light ray propagation. The use of smartphones with manual focus features can be a valuable tool for optics labs and can also be utilized by students for extracurricular learning. [Extracted from the article]

Electromagnetic metasurfaces have been playing exotic roles in the construction of ultracompact and versatile metadevices for wave–matter interactions. So far, multiple metasurfaces cascaded with intercouplings have been intensively investigated for extraordinary wavefront control and broadband spectral regulations. However, most cases face high structural complexity and little attention is paid to cascaded metasurfaces without interlayer couplings. In this paper, we demonstrate one type of terahertz Bragg mirror with ideally high reflectivity and ultra-broad bandwidth by simply resorting to decoupled metasurfaces. Cascaded metasurfaces with decoupled mode control prove practically straightforward for analytical design and easy to fabricate for engineering purpose in our scheme. Essentially, by flexibly tuning the decoupled metasurface mode, the middle Fabry–Perot mode that behaves like a defect mode inside the reflective passband can be eliminated for substantial band expanding. Fundamental analyses and rigorous calculations are performed to confirm the feasibility of our metasurface-based THz Bragg mirror with scalable bandgap. In comparison, our meta-mirror provides superior spectral performance of a larger bandgap and higher in-band reflectivity over that composed by ten layers of alternate dielectrics (Rogers 3003 and 3005). Finally, our analytical methodology and numerical results provide a promising way for the rapid design and fabrication of a Bragg mirror in the optical regime. [ABSTRACT FROM AUTHOR]

In recent years, active research has been conducted on X-ray computed tomography (CT) scans for observing and analyzing the internal structures and defects of products. High-precision is often required for products with primitive shapes, such as X-ray rotating ellipsoidal focusing mirrors, which are used for high-resolution observations. However, the CT reconstruction algorithm can cause blurring and artifacts in the CT volume, thereby complicating the accurate determination of the surface position. To address this issue, we propose an algorithm for high-precision surface extraction from the CT volume of primitive shapes. To accurately determine the surface position on the CT volume influenced by partial volume effects, we introduce three methods for primitive fitting. The first method approximates the boundary between the mirror and air in each cross-section with a line. The second method uses a local cylindrical approximation for the boundary, whereas the third method locally fits the primitive shape to the mirror for each cross-section. By comparing the outcomes of the proposed algorithm with those of conventional surface extraction algorithms, we demonstrate the superior accuracy of our approach and discuss the characteristics of various methods. Overall, the algorithm contributes toward enhancing the accuracy of internal structure analysis and defect detection in industrial components, potentially reducing manufacturing errors and improving product quality. [ABSTRACT FROM AUTHOR]

Confusing object detection (COD), such as glass, mirrors, and camouflaged objects, represents a burgeoning visual detection task centered on pinpointing and distinguishing concealed targets within intricate backgrounds, leveraging deep learning methodologies. Despite garnering increasing attention in computer vision, the focus of most existing works leans toward formulating task-specific solutions rather than delving into in-depth analyses of methodological structures. As of now, there is a notable absence of a comprehensive systematic review that focuses on recently proposed deep learning-based models for these specific tasks. To fill this gap, our study presents a pioneering review that covers both the models and the publicly available benchmark datasets, while also identifying potential directions for future research in this field. The current dataset primarily focuses on single confusing object detection at the image level, with some studies extending to video-level data. We conduct an in-depth analysis of deep learning architectures, revealing that the current state-of-the-art (SOTA) COD methods demonstrate promising performance in single object detection. We also compile and provide detailed descriptions of widely used datasets relevant to these detection tasks. Our endeavor extends to discussing the limitations observed in current methodologies, alongside proposed solutions aimed at enhancing detection accuracy. Additionally, we deliberate on relevant applications and outline future research trajectories, aiming to catalyze advancements in the field of glass, mirror, and camouflaged object detection. [ABSTRACT FROM AUTHOR]

Modeling the behavior of a prototype cantilevered X-ray adaptive mirror (held from one end) demonstrates its potential for use on high-performance X-ray beamlines. Similar adaptive mirrors are used on X-ray beamlines to compensate optical aberrations, control wavefronts and tune mirror focal distances at will. Controlled by 1D arrays of piezoceramic actuators, these glancing-incidence mirrors can provide nanometre-scale surface shape adjustment capabilities. However, significant engineering challenges remain for mounting them with low distortion and low environmental sensitivity. Finite-element analysis is used to predict the micron-scale full actuation surface shape from each channel and then linear modeling is applied to investigate the mirrors' ability to reach target profiles. Using either uniform or arbitrary spatial weighting, actuator voltages are optimized using a Moore–Penrose matrix inverse, or pseudoinverse, revealing a spatial dependence on the shape fitting with increasing fidelity farther from the mount.