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The accurate extraction of useful signals from the measurement data is one of the important parts and challenges of the understanding of subsurface information. The desired signal is usually hidden in the background noise, and the amplitude is weak due to the particular geological environment of the subsurface or the consistency of the measuring instrument. By extending the theory of seismic interferometry to include the effects of adjacent virtual channels and by combining super- and reverse-virtual interferometry, we obtain a hybrid virtual interferometry technique based on stacking neighboring virtual traces for wave reconstruction. We have verified the effectiveness of the processing method in suppressing noise interference and extracting useful signals using synthetic data tests. The method is applied to the processing and interpretation of acoustic measurements acquired in a cased borehole of a coal formation and an open hole of an igneous formation, where the processed waveforms are finely reconstructed, and the estimated slowness results are in good agreement with other measurements, thus providing an effective tool for data analysis. [ABSTRACT FROM AUTHOR]

The estimation of elastic properties of thin-bed formations from sonic logging is challenging. Standard slowness processing of sonic logging waveforms typically yields an average slowness log profile over the span of the receiver array, obscuring thin-layer features smaller than the array aperture. In order to enhance vertical resolution of the slowness logs, the subarray processing techniques have been developed. However, for the subarrays with smaller aperture, the semblance from subarray waveforms becomes susceptible to noise, which results in a low signal-to-noise (S/N) ratio for the processing slowness logs. To overcome the above drawbacks, we propose a slowness estimation method with the enhanced resolution ranging from the conventional array aperture resolution to the inter-receiver spacing based on the reconstruction of neighboring virtual traces (RNVTs). The method utilizes super-virtual interferometry to reconstruct a large number of waveforms for slowness extraction using redundant information from overlapping receiver subarrays. We validate the feasibility and effectiveness of the proposed method using synthetic numerical experiments. By adding different levels of noise to synthetic data, we conclude that the new method has better noise robustness. Finally, we apply this method to field data, and the estimated high-resolution slowness logs show good agreement in interbedded sand-shale sequences. Both numerical tests and examples of field data show that, the slowness logs estimated by the new method can be obtained with a high resolution as well as with a high S/N ratio, providing an effective method for assessing slowness properties from a borehole. [ABSTRACT FROM AUTHOR]

Snakes in the family Elapidae largely produce venoms rich in three-finger toxins (3FTx) that bind to the α 1 subunit of nicotinic acetylcholine receptors (nAChRs), impeding ion channel activity. These neurotoxins immobilize the prey by disrupting muscle contraction. Coral snakes of the genus Micrurus are specialist predators who produce many 3FTx, making them an interesting system for examining the coevolution of these toxins and their targets in prey animals. We used a bio-layer interferometry technique to measure the binding interaction between 15 Micrurus venoms and 12 taxon-specific mimotopes designed to resemble the orthosteric binding region of the muscular nAChR subunit. We found that Micrurus venoms vary greatly in their potency on this assay and that this variation follows phylogenetic patterns rather than previously reported patterns of venom composition. The long-tailed Micrurus tend to have greater binding to nAChR orthosteric sites than their short-tailed relatives and we conclude this is the likely ancestral state. The repeated loss of this activity may be due to the evolution of 3FTx that bind to other regions of the nAChR. We also observed variations in the potency of the venoms depending on the taxon of the target mimotope. Rather than a pattern of prey-specificity, we found that mimotopes modeled after snake nAChRs are less susceptible to Micrurus venoms and that this resistance is partly due to a characteristic tryptophan → serine mutation within the orthosteric site in all snake mimotopes. This resistance may be part of a Red Queen arms race between coral snakes and their prey. [ABSTRACT FROM AUTHOR]

More than a century ago, Albert Einstein presented his general theory of gravitation (GR) to the Prussian Academy of Sciences. One of the predictions of the theory is that not only particles and objects with mass, but also the quanta of light, photons, are tied to the curvature of space-time, and thus to gravity. There must be a critical compactness, above which photons cannot escape. These are black holes (henceforth BH). It took 50 years after the theory was announced before possible candidate objects were identified by observational astronomy. And another 50 years have passed, until we finally have in hand detailed and credible experimental evidence that BHs of 10 to 10 10 times the mass of the Sun exist in the Universe. Three very different experimental techniques, but all based on Michelson interferometry or Fourier-inversion spatial interferometry have enabled the critical experimental breakthroughs. It has now become possible to investigate the space-time structure in the vicinity of the event horizons of BHs. We briefly summarize these interferometric techniques, and discuss the spectacular recent improvements achieved with all three techniques. Finally, we sketch where the path of exploration and inquiry may go on in the next decades. [ABSTRACT FROM AUTHOR]

In the framework of the ALOHA (Astronomical Light Optical Hybrid Analysis) project, dedicated to high resolution imaging in the L-band using optical fibre and nonlinear optics, we have implemented a servo controlled hectometric outdoor fibre link between two telescopes and the recombination beam facility of the CHARA telescope array. A two-stage servo system using optical fibre modulator, fibre delay line, and a metrology laser at 1064 nm allows to stabilise the optical path difference within 3 nm RMS over a 3000 s record. Using an internal source at 810 nm, the signal-to-noise ratio of the fringe modulation peak is enhanced by a factor better than two when the servo control is switched on. This study can be also considered as a seminal work towards very long base fibre linked telescope arrays and allows to scale the perturbative environment of an outdoor fibre link. [ABSTRACT FROM AUTHOR]

The retrieval of surface waves from ambient noise is important for delineating the solid earth's near-surface structures, especially in urban environments. Seismic interferometry (SI) with linear arrays is becoming popular in urban areas with abundant anthropogenic noise. However, retrieving the noise correlation functions (NCFs) is usually challenging for a dense linear array under the demand of short-time recordings and the limited number of stations in urban environments. We comprehensively compare the SI and three-station interferometry, and the results show that the convolution-based three-station interferometry can accurately retrieve the NCFs using short-time recordings for dense linear arrays from traffic-induced noise. A synthetic example demonstrates the superiority of the convolution-based three-station interferometry over the traditional SI and the correlation-based three-station interferometry. Results from two field examples validate the convolution-based three-station interferometry for linear arrays deployed synchronously and asynchronously and confirm its advantage for multi-component data. We conclude that the convolution-based three-station interferometry performs better because it makes better use of linear arrays with short-time recordings and retrieves higher-quality NCFs. [ABSTRACT FROM AUTHOR]

Aptamers are increasingly employed in SARS-CoV-2 theragnostics in recent years. Characterization of aptamers, testing affinity and kinetic parameters (e.g., equilibrium dissociation constant (KD), kon, and koff), can be done by several methods and influenced by many factors. This study aims to characterize the binding of aptamers to SARS-CoV-2 nucleocapsid (N) protein using capillary electrophoresis (CE) and bio-layer interferometry (BLI). These two analytical methods differ by how the aptamer binds to its target protein once the aptamer, as a capture ligand, is partitioned in solution (CE) or immobilized on the biosensor (BLI). With CE, the KD values of the N-binding aptamers (tNSP1, tNSP2, and tNSP3) were determined to be 18 ± 4 nM, 45 ± 11 nM, and 32 ± 7 nM, respectively, while the KD measurements by BLI yielded 4.8 ± 0.6, 4.5 ± 0.5, and 2.9 ± 0.3 nM, respectively. CE results showed a higher KD across all aptamers tested. The differences in the steric hindrance and confirmational structures of the aptamers immobilized on the BLI biosensors versus those suspended in the CE sample solution affect the molecular interactions between aptamers and the target proteins. Moreover, the buffer composition including pH and ionic strength can influence the stability of aptamer structures, or aptamer-protein complexes. All these variables affect the binding and calculated KD. In this sense, a KD value alone is not sufficient to make comparisons between aptamers; instead, the entire experimental setup should also be considered. This is particularly important when implementing aptamers in different bioanalytical systems. [ABSTRACT FROM AUTHOR]

The detection of weak time-dependent alternating signals in a strongly noisy background is an important problem in physics and a critical task in metrology. Quantum lock-in amplifier can extract alternating signals within extreme noises by using suitable quantum resources, which has been widely used for magnetic field sensing, vector light shift detection, and force detection. In particular, entanglement-enhanced quantum lock-in amplifier can be realized via many-body quantum interferometry. The many-body lock-in measurement provides a feasible way to achieve high-precision detection of alternating signals, even in noisy environments. In this article, we review general protocol, experiment progresses and potential applications of quantum lock-in measurements. [ABSTRACT FROM AUTHOR]

The electro-brush plating process is flexible, and its deposition rate is relatively fast. However, the pretreatment process of brush plating is cumbersome, which leads to many problems in practical applications. The impact of different pretreatment techniques on the surface quality and the related properties of Ni-Co-Al2O3 nanocomposite coatings electro-brushed on 45 steel substrates were studied in this paper. The surface roughness, morphology, cross-sectional morphology, and the thickness of deposited layers were analyzed by white-light interferometry, SEM, and metallographic microscopy. The adhesion, hardness, and elastic-plastic mechanical properties of Ni-Co-Al2O3 nanocomposite coatings were discussed in-detail by scratch tester, hardness tester, and nanoindenter. The results show that the two-step method of alkali solution–hydrochloric acid not only has a simple process but also a good pretreatment effect. The Ni-Co-Al2O3 nanocomposite coating obtained by this method is flat, uniform, and has fewer defects. The prepared coating thickness reaches 11.68 µm, the average hardness value is 630 HV, and the elastic recovery ratio he/hmax value is 0.28. The adhesion between the coating and the substrate is significantly better than that of the traditional electro-brush plating process. This is expected to open a new path for the optimization and industrial application of the electro-brush plating process. [ABSTRACT FROM AUTHOR]

Backscatter interferometry (BSI) is a refractive index (RI) detection method that is easily integrated with capillary electrophoresis (CE) and is capable of detecting species ranging from inorganic ions to proteins without additional labels or contrast agents. The BSI signal changes linearly with the square of the separation voltage which has been used to quantify sample injection, but has not been explored as a potential signal enhancement mechanism in CE. Here we develop a mathematical model that predicts a signal enhancement at high field strengths, where the BSI signal is dominated by the voltage dependent mechanism. This is confirmed in both simulation and experiment, which show that the analyte peak area grows linearly with separation voltage at high field strengths. This effect can be exploited by adjusting the background electrolyte (BGE) to increase the conductivity difference between the BGE and analyte zones, which is shown to improve BSI performance. We also show that this approach has utility in small bore capillaries where larger separation fields can be applied before excess Joule heating degrades the separation. Unlike other optical detection methods that generally degrade as the optical pathlength is reduced, the BSI signal-to-noise can improve in small bore capillaries as the larger separation fields enhance the signal. [ABSTRACT FROM AUTHOR]

Although our every-day experience rejects it, the quantum Cheshire Cat suggests a potential spatial separation between different properties of a single particle in an interferometer. The first experiment with neutrons confirmed the quantum Cheshire Cat effect by using the path and spin degrees of freedom. The locations of each property are determined qualitatively through reactions to locally applied perturbations. Yet, no consensus on the interpretation has been reached. To clarify the origin of the effect, in the present experiment the energy degree of freedom is used as the third property; the three properties of neutrons appear to be separated in different paths in the interferometer. The analysis of the experiment suggests the strong involvement of the inner product between the state vectors, one evolved from the initial state through the perturbation and the other being the final state. The inner product results in amplitudes from two sub-beams which contribute to the intensity. The cross-term between amplitudes gives rise to the quantum Cheshire Cat. The Cheshire Cat phenomenon in quantum mechanics refers to a captivating observation where a particle and its properties behave as if they were separated. Here, the authors show the possibility of observing the Cheshire Cat phenomenon via interferometric neutron experiments in agreement with a weak measurement theoretical approach. [ABSTRACT FROM AUTHOR]

Cellulose, the basic biopolymer of plants, has unique optical characteristics due to its inherent birefringence. In this review, we summarize reported birefringence values for cellulose from the literature and describe its measurement techniques, including ellipsometry, interferometry, spectrophotometry and photothermometry. We also discuss the main dispersion models that have been proposed to explain the wavelength dependence of cellulose birefringence. Furthermore, we outline the diverse applications of cellulose birefringence, with a particular focus on biomedicine. Finally, we discuss the future prospects for cellulose birefringence. Overall, this review provides valuable insights into the basic research and practical application of cellulose birefringence and will stimulate new research and innovation in various fields. [ABSTRACT FROM AUTHOR]

We theoretically describe a driven two-electron four-level double-quantum dot (DQD) tunnel coupled to a fermionic sea using the rate-equation formalism. This approach allows to find occupation probabilities of each DQD energy level in a relatively simple way, compared to other methods. Calculated dependencies are compared with the experimental results. The system under study is irradiated by a strong driving signal, and as a result, one can observe Landau–Zener–Stückelberg–Majorana (LZSM) interferometry patterns which are successfully described by the considered formalism. The system operation regime depends on the amplitude of the excitation signal and the energy detuning, so one can transfer the system to the necessary quantum state in the most efficient way by setting these parameters. Obtained results give insights about initializing, characterizing, and controlling the quantum system states. [ABSTRACT FROM AUTHOR]

In high-sensitive laser interferometers, such as the gravitational-wave detector KAGRA, ultra-high-quality mirrors are essential. In the case of KAGRA, where cavity mirrors are cooled down to 20 K, large-size Sapphire crystals are used as the substrate for the main mirrors to achieve both a good optical quality (i.e., low absorption and uniform refractive index) and optimized thermal behavior under cryogenic temperatures. To implement the very tight optical specifications required by this demanding application, it is mandatory to test the optical homogeneity of different substrates. In order to characterize refractive-index inhomogeneities of large-size uniaxial samples such as the KAGRA Sapphire test masses, we developed a dedicated setup, allowing to resolve birefringence changes with a sensitivity in the order of Δ n ≈ 2 × 10 - 10 and a spatial resolution of 1 mm 2 . Moreover, the same setup allows us to simultaneously record residual absorption maps, thus allowing for a comparison between birefringence and absorption features. In this paper, we will present for the first time measurements on a KAGRA-sized Sapphire substrate which has been characterized in terms of absorption already in an earlier work. Both birefringence inhomogeneities and absorption distributions will be compared and correlations discussed. [ABSTRACT FROM AUTHOR]

The field of nanowire (NW) technology represents an exciting and steadily growing research area with applications in ultra-sensitive mass and force sensing. Existing detection methods for NW deflection and oscillation include optical and field emission approaches. However, they are challenging for detecting small diameter NWs because of the heating produced by the laser beam and the impact of the high electric field. Alternatively, the deflection of a NW can be detected indirectly by co-resonantly coupling the NW to a cantilever and measuring it using a scanning probe microscope. Here, we prove experimentally that co-resonantly coupled devices are sensitive to small force derivatives similar to standalone NWs. We detect force derivatives as small as 10−9 N/m with a bandwidth of 1 Hz at room temperature. Furthermore, the measured hybrid vibration modes show clear signatures of avoided crossing. The detection technique presented in this work verifies a major step in boosting NW-based force and mass sensing. Flexural oscillations of singly-clamped nanowires can be detected by interferometry for diameters above 50 nm, while below such diameter the detection becomes challenging. The authors detect force derivatives as small as 10-9 N/m at room temperature by measuring hybrid vibration modes originated by coupling a nanowire and a cantilever. [ABSTRACT FROM AUTHOR]

The paper presents the results of the processing of satellite radar images acquired by the TerraSAR-X satellite using the persistent scatterer method for analyzing the subsidence of the earth's surface over potash mines in the city of Berezniki, Perm Krai. A sequence of processing procedures in the GAMMA Software package (Gamma Remote Sensing AG, Switzerland) is presented, which showed good results in the conditions of this territory. A comparison is made with the results obtained earlier by summation of interferograms. In contrast to the methods of persistent scatterers, the summation is performed without analyzing displacements in time. The noisy time series obtained by the summation are not rejected, so the displacement maps cover the study area more evenly. In the persistent scatterer method, the time series is analyzed using a variety of criteria, so the subsidence rates are estimated more reliably. In the areas where the results were obtained by summation and the persistent scatterer method, the subsidence rates are in good agreement. The persistent scatterer method has made it possible to estimate displacements in certain areas separated by vast incoherent woodlands, on which interferograms lose their coherence. At the same time, a new subsidence area was identified with an average rate of subvertical displacements up to 75 mm/year and, in some areas, up to 100 mm/year, which, according to data for 2020 and 2018, was not detected. The subsidence here should be clarified based on the images for subsequent years or using surface thechniques. The time series also show the deceleration of subsidence in spring on persistent scatterers located on buildings and infrastructure. We associate the total spring deceleration of subsidence by 3–5 cm not with underground but with seasonal factors, specifically with the heating of buildings in the spring. Other reasons are also possible, but the main one is that, in areas with a moderate subsidence rate, this effect can lead to some underestimation of the average subsidence rate. A detailed study of the time series for subsidence makes it possible to identify areas requiring special attention. Most of the subsidence occurs more or less evenly; in a significant part of the territory, the subsidence rate in 2021 has decreased. This indicates the effectiveness of the measures taken to protect the ground infrastructure. Within the city area, the acceleration of subsidence was found only at the beginning of Lenin Avenue. SAR interferometry is an effective tool for studying subsidence processes in the city of Berezniki. This method significantly complements geodetic works, since it provides data on vast areas that cannot be covered by detailed ground measurements. In addition, part of the closed territories becomes dangerous for ground works, so there is no alternative to satellite technologies. [ABSTRACT FROM AUTHOR]

Using different methods for processing SAR images from the Sentinel-1A satellite, the displacement fields were determined in the region of the East Anatolian Fault Zone (EAFZ) and the Sürgü-Çardak faults, as well as a small fault on the continuation of the East Hatay fault zone, which rupture initiated a series of catastrophic earthquakes in Turkey on February 6, 2023. DInSAR and offset methods were applied. The most detailed data on the displacements were obtained by the offset method using images from the descending orbit. When constructing the model from the available SAR data, the data with the maximum signal-to-noise ratio were selected. For the northern part of the region, above 37.4° N, the range displacements obtained by the offset method from a descending orbit were used. South of parallel 37.0° N, we used azimuth displacements from the same descending orbit. The model of the seismic rupture was constructed on the basis of solution of (Pollitz, 1996) of the problem of deformations at the surface of a layered spherical Earth caused by along dip and strike displacements on a rectangular fault located inside the planet. Pollitz (1996) demonstrated that ignoring the radial layering of the planet leads to errors up to 20%, with the largest errors occurring in the presence of a large strike-slip component. Ignoring sphericity also introduces an error when using the solution in the framework of the idealization of an elastic homogeneous half-space with a flat free surface (Okada, 1985) which was used when constructing USGS and (Barbot et al., 2023) models. In our model the surfaces of seismic rupture are approximated by 19 rectangular elements along the strike, divided into three levels along the dip. Another element approximated a rupture along the extension of the East Hatay Fault Zone. As in the models of other authors (USGS; Barbot et al., 2023), in our model in the southern part of the EAFZ, the displacements increase from south to north, and are mainly concentrated in the upper part of the Earth's crust to a depth of 10 km. At the southern end of this rupture, displacements in our model with an amplitude of up to 2 m are obtained at the lower levels of the model, and at its upper level, the displacements were only 0.11 m, and in this area on February 20, 2023 an earthquake of magnitude 6.3 occurred with a hypocenter depth of 11.5 km. The main displacements on the EAFZ are determined on its central segment. Here, the displacements go to a greater depth, their value reaches 10.2 m. On the Sürgü-Çardak fault, significant displacements occurred down to a depth of 20 km; displacements exceeded 10.2 m. In our model, at the northeast end of the seismic rupture along the EAFZ, a displacement area of 6.8 m overlaps with the southwest end of the seismic rupture model of the Doğanyol-Sivrice earthquake of January 24, 2020 with Mw 6.7, published on the USGS website. Therefore, our model does not confirm the hypothesis of the presence of a seismic gap here, which, according to (Barbot et al., 2023), is a zone of a possible nearest earthquake. [ABSTRACT FROM AUTHOR]

This article discusses a measurement module of a dispersion interferometer based on a CO2 laser for integral plasma density measurements with a resolution of 4 × 1011 cm–2 with a time discreteness of 4 µs. Such characteristics of the device make it possible to use the results of its measurements in feedback loops for plasma density control. The main elements of the measurement module are crystals of analog-to-digital converters (ADCs) and a digital streaming data processing node based on a field-programmable gate array (FPGA). The algorithm for calculating the plasma density implemented in the digital node is based on the harmonic analysis of interferometer signals and is resistant to noise and changes in the modulation depth. The measurement module under consideration is a prototype of the system of monitoring and automatic control of plasma density at the Globus-M2 facility (St. Petersburg, Russia). [ABSTRACT FROM AUTHOR]

Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a multi-purpose experimental technique aimed at enhancing the science return of planetary missions. The technique exploits the science payload and spacecraft service systems without requiring a dedicated onboard instrumentation or imposing on the existing instrumentation any special for PRIDE requirements. PRIDE is based on the near-field phase-referencing Very Long Baseline Interferometry (VLBI) and evaluation of the Doppler shift of the radio signal transmitted by spacecraft by observing it with multiple Earth-based radio telescopes. The methodology of PRIDE has been developed initially at the Joint Institute for VLBI ERIC (JIVE) for tracking the ESA's Huygens Probe during its descent in the atmosphere of Titan in 2005. From that point on, the technique has been demonstrated for various planetary and other space science missions. The estimates of lateral position of the target spacecraft are done using the phase-referencing VLBI technique. Together with radial Doppler estimates, these observables can be used for a variety of applications, including improving the knowledge of the spacecraft state vector. The PRIDE measurements can be applied to a broad scope of research fields including studies of atmospheres through the use of radio occultations, the improvement of planetary and satellite ephemerides, as well as gravity field parameters and other geodetic properties of interest, and estimations of interplanetary plasma properties. This paper presents the implementation of PRIDE as a component of the ESA's Jupiter Icy Moons Explorer (JUICE) mission. [ABSTRACT FROM AUTHOR]

We compare two methods of millimeter radio interferometry with and without frequency conversion using as an example experimental measurements of the transverse deformation magnitude of a metal rod under dynamic load. We reveal a good agreement between the results, demonstrating a possibility of measuring the surface deviations within times of about 1 μs with micron precision. [ABSTRACT FROM AUTHOR]

Optical diffractometry (OD) using a phase step is an alternative for interferometry, further, has least sensitivity to environmental vibrations. Therefore, OD has found numerous interesting metrological and technological applications. OD utilizes a phase step to detect the influence of objects under measurement by the changes in the Fresnel diffraction pattern. Recently, we showed that such measurements do not require infinitively sharp phase steps, although fabrication of such sharp elements is also impossible. Here, we address the issue of smoothness of the phase step surfaces. So far, in all of the OD applications the surfaces of the incorporated phase steps are considered to be optically smooth and flat. However, practically, some amount of roughness and unflatness is unavoidable even in precise and careful fabrication process. We show that preserving the OD-diffraction-pattern characteristics of a phase step depends on the level of roughness in the surfaces of the phase step. We define number of detectable fringes and autocorrelation functions of the diffraction patterns as the measures for evaluating the similarity of the rough phase step diffractions to the ideal case. We derive the theoretical description and confirm the results with simulations and experiments. [ABSTRACT FROM AUTHOR]

On January 18, 2021, a moderate earthquake (Mw 6.5) occurred ~ 45 km southwest of San Juan, a city in Central-Western Argentina, at a relatively shallow depth of ~ 20 km. The earthquake caused damage to the environment and infrastructure in the affected area, which is home to ~ 600,000 residents. To assess ground deformation, identify the seismogenic source, and evaluate the extent of secondary effects, we utilized Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques in combination with Sentinel-2 visible and infrared imagery, as well as field data. DInSAR results suggested centimeter-scale ground deformation around the epicenter, off-fault deformation linked to regional structures, and site effects, such as liquefaction and landslides. By combining the values extracted from a 3-year-long PSI and SBAS time series, we estimated a vertical displacement of approximately 4.5 cm near the epicenter. Off-fault deformation involves some degree of ground settling on top of a blind or buried section of the Papagallos fault system, the reactivation of a section of the Rinconada fault system, and liquefaction and ground settling processes in the Tulum Valley. Rockfalls were distributed throughout a geologically diverse terrain and along a NW swath, with their occurrence controlled by the shaking intensity. The total area affected by secondary effects was ~ 3800 km2. Based on the available focal mechanism solutions and the distribution of environmental damage, we propose a left-lateral strike-slip displacement in a blind NW-striking fault, although different interpretations are discussed. Finally, we estimated the epicentral depth from SBAS time series Bayesian Inversion and from differential travel times pP-P, obtaining a depth of 20–25 km. [ABSTRACT FROM AUTHOR]

Near-surface seismic shear wave is a basic tool for seismic investigations. However, its frequency-dependent property is not fully investigated, especially by the in situ observation method. Here, we develop the seismic interferometry with a moving frequency window to process the natural seismic signals recorded by the KiK-net network. It is observed that the phase velocity of the shear wave decreases sharply as the frequency increases in the low-frequency range, and remains constant in the high-frequency range. The observed dispersion phenomenon presents a challenge to existing site effect prediction theories, while also providing an observational reference for understanding how the shear wave propagates in near-surface sediment. Key points: Moving-frequency-window seismic interferometry is developed to extract the frequency-varying information of the ground motion. It is firstly observed that the shear wave velocity in near-surface sediment is strongly frequency-dependent. The phase velocity of the shear wave decreases sharply in the low-frequency range as the frequency increases. [ABSTRACT FROM AUTHOR]

Coherent dissipative structures known as platicons can be reliably generated in photonic molecules, resulting in deterministic and reproducible microcombs derived from a continuous-wave pump. However, the supermode spectrum of standard photonic molecules displays numerous avoided mode crossings, distorting the spectral envelope of platicon microcombs. Here, we obtain a platicon microcomb using a photonic molecule configuration based on two coupled microcavities, whose size differs by an order of magnitude. This results in an engineered microcomb spectrum that closely resembles the one generated in an ideal single microresonator with just one frequency mode shift. We observe the coupling between the repetition rate of the platicon microcomb with the frequency of the pump laser, an effect originating from the dispersive-wave recoil induced by mode crossings. Using two identical platicon microcombs, we make use of such coupling to realize dual-comb interferometry. These results contribute to understanding dissipative structures in normal-dispersion microresonators and offer an alternative to applications such as spectroscopy and metrology. Platicons microcombs can be generated in photonic molecules from a continuous-wave pump, but their spectrum is typically distorted. The authors observe the formation of a platicon microcomb using a photonic molecule realized with two coupled microcavities, resulting in engineered microcomb spectrum approaching the ideal single microresonator case. [ABSTRACT FROM AUTHOR]

Interior automotive plastic components are often manufactured by injection moulding since this technique enables cost-efficient manufacturing, large design freedom, and easy integration of functions. However, to obtain a high-quality impression, it is important to produce components with uniformity in texture, colour, and gloss. Unfortunately, this is rather difficult since a large number of material and processing parameters affect the surface topography and thereby the texture, colour, and gloss. It is therefore important to improve the understanding of how different material and processing parameters affect the surface topography, and in the present study, the influence on surface topography of ABS (Acrylonitrile Butadiene Styrene) and PP (Polypropylene) by melt temperature, tool temperature, and injection speed is investigated by coherence scanning interferometry. Area scale analysis is used to identify the wavelengths of interest, and areal surface parameters are statistically screened to identify robust surface parameters that can be used to discriminate between the surfaces and quantify the influence on surface topography by different material and process variables. Results from the study suggest that tool temperature and injection speed have significant influence on certain surface parameters and, particularly, arithmetic mean height (Sa) and root mean square gradient (Sdq) by approximately 40%, core material volume (Vmc) by 35%, and core roughness depth (Sk) by 50%. These surface parameters are identified as significant and used to discriminate between the sample surfaces. [ABSTRACT FROM AUTHOR]

In vitro biopanning platforms using synthetic phage display antibody libraries have enabled the identification of antibodies against antigens that were once thought to be beyond the scope of immunization. Applying these methods against challenging targets remains a critical challenge. Here, we present a new biopanning pipeline, RAPID (Rare Antibody Phage Isolation and Discrimination), for the identification of rare high-affinity antibodies against challenging targets. RAPID biopanning uses fluorescent labeled phage displayed fragment antigen-binding (Fab) antibody libraries for the isolation of high-affinity binders with fluorescent activated sorting. Subsequently, discriminatory hit screening is performed with a biolayer interferometry (BLI) method, BIAS (Biolayer Interferometry Antibody Screen), where candidate binders are ranked and prioritized according to their estimated kinetic off rates. Previously reported antibodies were used to develop the methodology, and the RAPID biopanning pipeline was applied to three challenging targets (CHIP, Gαq, and CS3D), enabling the identification of high-affinity antibodies. A FACS aided selection process combined with characterization of the selected clones facilitates phage display screening to obtain antibodies against a given target from libraries. [ABSTRACT FROM AUTHOR]

This paper presents a new model of seismic rupture surface for the Chignik Mw 8.2 earthquake which occurred off the Alaska Peninsula on July 29, 2021. The model is based on data on surface displacements obtained by satellite radar interferometry from Sentinel-1A and 1B images and on horizontal GPS displacements in the area of this earthquake. We used satellite radar images for the period between July 17 and August 10, 2021, as well as GPS data for the period between July 18 and August 8, 2021. All of these displacements include both coseismic movements and some postseismic displacements. The rupture surface model was developed using F. Pollitz' solution to the problem concerning the displacement field at the surface of a spherical radially stratified planet due to a rectangular rupture inside the planet. The inversion was regularized by requiring that the direction of displacement at each element of the rupture plane be close to a specified direction as given by seismological data. The seismic rupture surface in this model is fitted by a plane extending for 225 km along strike and 126 km along dip, and which is subdivided into 48 identical elements. According to the model derived here, the type of displacement is a nearly pure thrust, with the displacement in general involving all of the rupture zone. The maximum slip was 5.7 m, with the mean slip as averaged over the entire rupture plane being 2.2 m. Assuming the shear modulus to be 32 GPa, we found the seismic moment based on the parameters of the plane we have derived and on the displacements on it as 1.95 × 1021 N m (Мw = 8.13), which is near the USGS and GCMT estimates based on seismological data. [ABSTRACT FROM AUTHOR]

The Mw 7.6 Olyutorskii earthquake of April 20, 2006, struck the southern edge of the Koryak Highland, in a region of great complexity at the junction of the North American, Eurasian, and Pacific plates. This seismic event was notable for several remarkable features. Firstly, it had an unexpectedly large magnitude, leading to a reassessment of the seismic hazard in the Northern Kamchatka region. Secondly, the GCMT focal mechanism solution showed two nodal planes corresponding to nearly thrusting displacements on a 40–51° dipping rupture plane. However, geological field studies conducted in the epicentral area allow to map at the surface three primary segments of a 120 km long rupture zone. The central segment showed predominant right-lateral strike-slip displacements, while the NE and SW segments exhibited mostly thrusts steeply dipping SE with smaller strike-slip components. Thirdly, aftershocks were recorded in an area extending over 200 km southwestward from the surface ruptures mapped in the field, with an intense activity observed in a vast area 75 km to the NW from the surface ruptures. Fourthly, although the ruptures found during fieldwork were dipping to the SE, most aftershocks occurred NW of them, with their depth decreasing in the NW direction. SAR interferometry resolved this apparent discrepancy between seismological and field-geology data, indicating that the primary displacements occurred northwest from the central and southwest segments of the ruptures at the earth's surface. We present in our study a new rupture model based on SAR, GPS, and field geology data. The model consists of a major blind thrust extending NW and three rear subvertical ruptures that reached the earth's surface and were mapped during the field survey. Additionally, models of the main Mw 6.6 aftershocks that occurred on April 29, 2006, and May 22, 2006, are presented. Our new model reconciles all collected data, with a direction of movements on the major thrust agreeing with the rotation of the previously suggested Beringia microplate around a pole situated in the North of the Chukotka peninsula. [ABSTRACT FROM AUTHOR]

The definition of landslide hazard is a step-like procedure that encompasses the quantification of its spatial and temporal attributes, i.e., a reliable definition of landslide susceptibility and a detailed analysis of landslide recurrence. However, available information is often incomplete, fragmented and unsuitable for reliable quantitative analysis. Nevertheless, landslide hazard evaluation has a key role in the implementation of risk mitigation policies and an effort should be done to retrieve information and make it useful for this purpose. In this research, we go through this topic of optimising the information available in catalogues, starting from landslide inventory review and constitution of a boosted training dataset, propaedeutic for susceptibility analysis based on machine learning methods. The temporal recurrence of landslide events has been approached here either through the definitions of large-scale quantitative hazard descriptors or by analysis of historical rainfall (i.e., the main triggering factor for the considered shallow earth slope failures) databases through the definition of rainfall probability curves. Spatial and temporal attributes were integrated, selecting potential landslide source areas ranked in terms of hazard. Data integration was also pursued through persistent scatterer interferometry analysis which pointed out areas of interest within potential landslide source areas featured by ongoing ground movement. The consequential approach led to the definition of the first hazard product of the city of Rome at a local scale functional for advisory purposes or the statutory level, representing a thematic layer able to orient the risk managers and infrastructure stakeholders. [ABSTRACT FROM AUTHOR]

We propose a method to map the conventional optical interferometry setup into quantum circuits. The unknown phase shift inside a Mach–Zehnder interferometer in the presence of photon loss is estimated by simulating the quantum circuits. For this aim, we use the Bayesian approach in which the likelihood functions are needed, and they are obtained by simulating the appropriate quantum circuits. The precision of four different definite photon-number states of light, which all possess six photons, is compared. The measurement scheme that we have considered is counting the number of photons detected after the final beam splitter of the interferometer, and photon loss is modeled by using fictitious beam splitters in the arms of the interferometer. Our results indicate that three of the four definite photon-number states considered can have better precision than the standard interferometry limit whenever the photon loss rate is in a specific range. In addition, the Fisher information for the four definite photon-number states in the setup is also estimated to check the optimality of the chosen measurement scheme. [ABSTRACT FROM AUTHOR]

Slope failures frequently occur in open-pit mines, resulting in significant losses. Identifying the precursory displacements and triggering factors for detecting unstable slopes is critical for reducing and preventing their impact. This study proposes combining satellite radar interferometry and infrared thermography with numerical simulation to determine unstable slopes in an open-pit mine. First, interferometric synthetic aperture radar (InSAR) is utilized to capture deformation information in a line-of-sight direction in terms of velocity to locate the long-time movement on a large scale. The application of infrared thermography enables the detection of peculiar features based on the different thermal patterns occurring along the slope and the interpretation of critical sectors matching with the instability zones highlighted by the InSAR. In particular, areas with various surface temperatures were associated with vegetated spots, new benches, bare sectors, and contact between different lithologies. By means of three-dimensional stability analyses, the associated interferometry movement confirmed the slope instability, and a critical failure surface was found using two-dimensional numerical simulation. The efficacy of the proposed approach is verified through a massive slope failure in the Qidashan open-pit mine in Liaoning, China. It predicts the slope failures caused by intense rainfall and reveals the progressive failure mechanism. The practical application has demonstrated the feasibility and accuracy of the proposed approach for detecting failure precursors, providing a novel procedure for remotely identifying critical slopes in an open-pit with frequent mining activity. [ABSTRACT FROM AUTHOR]

An updated and complete landslide inventory is the starting point for an appropriate hazard assessment. This paper presents an improvement for landslide mapping by integrating data from two well-consolidated techniques: Differential Synthetic Aperture Radar (DInSAR) and Landscape Analysis through the normalised channel steepness index (ksn). The southwestern sector of the Sierra Nevada mountain range (Southern Spain) was selected as the case study. We first propose the double normalised steepness (ksnn) index, derived from the ksn index, to remove the active tectonics signal. The obtained ksnn anomalies (or knickzones) along rivers and the unstable ground areas from the DInSAR analysis rapidly highlighted the slopes of interest. Thus, we provided a new inventory of 28 landslides that implies an increase in the area affected by landslides compared with the previous mapping: 33.5% in the present study vs. 14.5% in the Spanish Land Movements Database. The two main typologies of identified landslides are Deep-Seated Gravitational Slope Deformations (DGSDs) and rockslides, with the prevalence of large DGSDs in Sierra Nevada being first revealed in this work. We also demonstrate that the combination of DInSAR and Landscape Analysis could overcome the limitations of each method for landslide detection. They also supported us in dealing with difficulties in recognising this type of landslides due to their poorly defined boundaries, a homogeneous lithology and the imprint of glacial and periglacial processes. Finally, a preliminary hazard perspective of these landslides was outlined. [ABSTRACT FROM AUTHOR]

Optical diffractometry (OD) using a phase step is an alternative for interferometry, further, has least sensitivity to environmental vibrations. Therefore, OD has found numerous interesting metrological and technological applications. OD utilizes a phase step to detect the influence of objects under measurement by the changes in the Fresnel diffraction pattern. Recently, we showed that such measurements do not require infinitively sharp phase steps, although fabrication of such sharp elements is also impossible. Here, we address the issue of smoothness of the phase step surfaces. So far, in all of the OD applications the surfaces of the incorporated phase steps are considered to be optically smooth and flat. However, practically, some amount of roughness and unflatness is unavoidable even in precise and careful fabrication process. We show that preserving the OD-diffraction-pattern characteristics of a phase step depends on the level of roughness in the surfaces of the phase step. We define number of detectable fringes and autocorrelation functions of the diffraction patterns as the measures for evaluating the similarity of the rough phase step diffractions to the ideal case. We derive the theoretical description and confirm the results with simulations and experiments. [ABSTRACT FROM AUTHOR]

Neutron Orbital Angular Momentum (OAM) is an additional quantum mechanical degree of freedom, useful in quantum information, and may provide more complete information on the neutron scattering amplitude of nuclei. Various methods for producing OAM in neutrons have been discussed. In this work we generalize magnetic methods which employ coherent averaging and apply this to neutron interferometry. Two aluminium prisms are inserted into a nested loop interferometer to generate a phase vortex lattice with significant extrinsic OAM, 〈Lz〉 ≈ 0.35, on a length scale of ≈ 220 μm, transverse to the propagation direction. Our generalized method exploits the strong nuclear interaction, enabling a tighter lattice. Combined with recent advances in neutron compound optics and split crystal interferometry our method may be applied to generate intrinsic neutron OAM states. Finally, we assert that, in its current state, our setup is directly applicable to anisotropic ultra small angle neutron scattering. Orbital angular momentum in thermal neutrons holds many promises for quantum information and neutron scattering, however the production thereof remains challenging. The authors detail a coherent averaging method, which can generate neutron vortices smaller than previously possible and can be applied to anisotropic ultra small angle scattering. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the redesign and additive manufacturing of a rocket engine nozzle using Inconel 625 material. The redesigned engine took into consideration material shrinkage during the metal transfer process. The additive manufacturing process was carried out using the appropriate toolpaths to form a solid structure. Micrographs of the additively manufactured structure showed layer resolution and fine detail, as well as the presence of metallic particles within the polymer matrix. The final rocket engine nozzle produced was found to have the necessary mechanical and metallurgical properties required for practical use in future space vehicle operations. This was demonstrated by tensile tests carried out at various temperatures and 3D white light interferometry scans of the surface properties. The results of the study suggest that additive manufacturing and Inconel 625 material can be used to produce high-performance rocket engine nozzles that meet the requirements of the aerospace industry. This study provides valuable insights into the potential applications of additive manufacturing in the aerospace industry and may lead to the development of new, high-performance rocket engine nozzles. [ABSTRACT FROM AUTHOR]

Despite the astonishing successes of quantum mechanics, due to some fundamental problems such as the measurement problem and quantum arrival time problem, the predictions of the theory are in some cases not quite clear and unique. Especially, there are various predictions for the joint spatiotemporal distribution of particle detection events on a screen, which are derived from different formulations and interpretations of the quantum theory. Although the differences are typically small, we show that these predictions can be experimentally distinguished by a proposed unconventional double-slit configuration, which is realizable using present-day single-atom interferometry. This experiment would enrich our understanding of the foundations of quantum mechanics. The measurement and quantum arrival time problems have originated various predictions for the join spatiotemporal distribution of particle detection events, derived from different formulations and interpretations of the quantum theory. By reworking the famous double-slit experiment, the authors propose a realizable setup to probe such predictions. [ABSTRACT FROM AUTHOR]

On Sept. 19th, 2021, a volcanic eruption began on the island of La Palma (Canary Islands, Spain). The pre-eruptive episode was characterized by seismicity and ground deformation that started only 9.5 days before the eruption. In this study, we applied seismic interferometry to the data recorded by six broadband seismic stations, allowing us to estimate velocity variations during the weeks preceding the eruption. About 9.5 days before the eruption, we observed a reduction in the seismic velocities is registered next to the eruptive centers that opened later. Furthermore, this zone overlaps with the epicenters of a cluster of volcano-tectonic earthquakes located at shallow depth (< 4 km) and detached from the main cluster of deeper seismicity. We interpret the decrease in seismic velocities and the occurrence of such a shallow earthquake cluster as the effect of hydrothermal fluid released by the ascending magma batch and reaching the surface faster than the magma itself. [ABSTRACT FROM AUTHOR]

Background: Heterodyne interferometry offers an exciting solution for achieving sub-nanometer or ten-picometer-order mechanical displacement measurements because of its high resolution and noise immunity. Objective: In this paper, we investigate the stability and resolution of a conventional displacement-measuring heterodyne interferometer using a single phase-locked loop (PLL) at a sub-nanometer or 10-pm level over an µm-scale measurement regime in normal air. Methods: In the experiment, we perform the beat frequency reduction of the heterodyne signals to take advantage of a low-cost frequency sampling data acquisition (DAQ). The primary calculations of the single phase-locked loop (PLL) algorithm are implemented in a point-by-point (pt-pt) construction, providing pt–pt low-pass filters (LPFs) with high noise suppression. The output is appended into an array of N points and averaged to reduce the noise of the outgoing signal again. Using the PLL phase meter with the beat frequency reduction can ensure a mdeg-order phase measurement with Allan deviation stability of ~ 10 µdeg over 1000 s. We consider a combination of the miniaturization of optical paths in air and the PLL phase meter integrated with low-cost devices while ensuring mdeg-order measurement stability to achieve the interferometer's pm-order measurement resolution and stability. Results: The measurement results show that the interferometer can achieve a resolution of 26 pm over a 5 μm-range mechanical displacement measurement. The Allan deviation stability of the interferometer reaches ~ 10 pm over a sampling time of 30 s, and the displacement noise floor is 10 pm/Hz1/2 above 1 Hz. Conclusions: The new signal-processing PLL phase meter provides higher noise reduction than the old one presented in our previous work. With low cost but high resolution and stability, the PLL phase meter is incredibly suitable for pm-order displacement-measuring heterodyne interferometry. Combining a well-reduced PLL phase meter and a conventional heterodyne interferometer with a stable, isolated configuration and the minimization of optical paths in the air can give the measurement system a high resolution and stability. The measurement system can have a more significantly improved resolution of a few tens of pm than interferometers presented in previous publications and stability comparable to the modified heterodyne interferometers shown in earlier works over the sampling time of 30 s (possibly up to 100 s). A conventional heterodyne interferometer with a single PLL is expected to perform large-range displacement measurements with resolution at ten picometer levels in air. [ABSTRACT FROM AUTHOR]

Two strike–slip faults, displacements along which caused the catastrophic earthquakes in Turkey on February 6, 2023, were mapped from satellite radar interferometry data. According to the satellite data, the relative displacements of the sides of the East Anatolian Fault Zone (EAFZ), with which the first event of Mw 7.8 was associated, exceeded 5 m in the central segment. The rupture surface extends from the area of the Doğanyol-Sivris earthquake Mw 6.7 of January 24, 2020, in the north to the Mediterranean coast in the south, where the earthquake Mw 6.3 occurred on February 20, 2023. The second event Mw 7.5 is associated with the Surgü-Çardak fault; the relative displacements of its sides, according to satellite data, exceeded 7 m. The obtained displacement fields of the Earth's surface were used to construct a model of the seismic rupture. This model was worked out on the basis of the Pollitz, 1996 solution, which defines displacements on the surface of the spherically stratified planet as a result of along dip and strike displacements on a rectangular rupture located inside the sphere. Ignoring the spherical stratification of the planet leads to errors of up to 20%, especially in the presence of a large strike–slip component [5]. Ignoring sphericity also causes an error, when using the solution obtained for an elastic homogeneous half-space, as the US Geological Survey (USGS) has done, in modeling the seismic rupture for earthquakes in Turkey in 2023. Our model differs in the detailed consideration of the fault geometry. For this purpose, the faults were approximated by 19 planes along the strike, divided into two levels along the dip. In our rupture model strike–slip displacements in the central segment of the EAFZ reached 12.7 m. In the southern segment of this rupture, the displacements are much smaller. It should be emphasized that we registered the displacements for the period from January 29, 2023, to February 10, 2023; therefore, together with co-seismic ones, they also include post-seismic displacements for four days after the main seismic events. The displacements on the rupture surface along the Surgü-Çardak Fault, where the Mw 7.5 earthquake occurred, were up to 10 m. The results demonstrate, in particular, the efficiency of application of the satellite radar interferometry in the operative study of catastrophic geodynamic phenomena and processes. [ABSTRACT FROM AUTHOR]

The geological effects of the Khubsugul earthquake of January 12, 2021, with Mw = 6.7, which became the strongest in the Khubsugul region during the instrumental stage of seismological observations, are studied and mapped. Using the ESI-2007 scale, the epicentral zone with intensity VIII is contoured. The primary seismic rupture is represented by the right-lateral strike–slip with a displacement amplitude up to 20 cm, which renewed the Late Holocene tectonic scarp on the western side of the Khubsugul rift basin. The dynamics of rupturing in the Late Holocene indicates the gradual expansion of the basin due to the destruction of the adjacent mountain range. The data of satellite interferometry and seismological observations are in good agreement with the results of the field studies, which allows considering the delineated region of maximum shaking as a projection of the upper part of the source zone onto the surface. [ABSTRACT FROM AUTHOR]

Synchrotron radiation, emitted by relativistic electrons traveling in a magnetic field, has poor temporal coherence. However, recent research has proved that time-domain interferometry experiments, which were thought to be enabled by only lasers of excellent temporal coherence, can be implemented with synchrotron radiation using a tandem undulator. The radiation generated by the tandem undulator comprises pairs of light wave packets, and the longitudinal coherence within a light wave packet pair is used to achieve time-domain interferometry. The time delay between two light wave packets, formed by a chicane for the electron trajectory, can be adjusted in the femtosecond range by a standard synchrotron technology. In this study, we show that frequency-domain spectra of the tandem undulator radiation exhibit fringe structures from which the time delay between a light wave packet pair can be determined with accuracy on the order of attoseconds. The feasibility and limitations of the frequency-domain interferometric determination of the time delay are examined. [ABSTRACT FROM AUTHOR]

A strong earthquake of Mw 7.3 hit the border region between Iran and Iraq on November 12, 2017. Several InSAR-based coseismic inversion studies suggested that the earthquake occurred on a northeast dipping Mountain Front Fault within the Precambrian Arabian basement. In this study, we use multiple ascending and descending pass C-band Sentinel-1 images to study the earthquake's pre- and post-seismic surface displacements. We performed SBAS time series from June 2017 to March 2018 to understand the spatiotemporal evolution of the displacement before and after the November event. The pre-seismic time series displacement values range as high as –89 mm in descending pass and –96 mm in ascending pass. The pre-seismic time series analysis reveals subsidence between 84 and 0 days before the earthquake, which might be due to excessive groundwater pumping. The post-seismic displacements showed logarithmic decay, indicating afterslip. Even though the earthquake occurred on a blind reverse fault, we highlight that the post-seismic afterslip is composed of horizontal and vertical deformation components, which can be inferred from the variation in the displacement values of the descending and ascending passes. We believe that the small magnitude earthquakes and the January 2018 Mandali earthquake sequence in the Zagros Mountain region affect the spatiotemporal evolution of the November event afterslip. Research Highlights: The temporal evolution of the pre-seismic displacement indicates significant ground subsidence before the earthquake. The pre-seismic ground subsidence due to excessive groundwater withdrawal combined with the interseismic strain accumulation might result in a reverse faulting earthquake. The results highlight the importance of the multi-temporal InSAR technique in the field of earthquake precursory studies. Several small magnitude earthquakes and the Mandali earthquake sequence that occurred after the earthquake affected the temporal evolution of the post-seismic afterslip. The pre-seismic deformation is dominantly vertical, whereas the post-seismic deformation is a combination of horizontal and vertical motion. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common type of cancer worldwide. Diagnosing breast cancer relies on clinical examination, imaging and biopsy. A core-needle biopsy enables a morphological and biochemical characterization of the cancer and is considered the gold standard for breast cancer diagnosis. A histopathological examination uses high-resolution microscopes with outstanding contrast in the 2D plane, but the spatial resolution in the third, Z-direction, is reduced. In the present paper, we propose two high-resolution table-top systems for phase-contrast X-ray tomography of soft-tissue samples. The first system implements a classical Talbot–Lau interferometer and allows to perform ex-vivo imaging of human breast samples with a voxel size of 5.57 μm. The second system with a comparable voxel size relies on a Sigray MAAST X-ray source with structured anode. For the first time, we demonstrate the applicability of the latter to perform X-ray imaging of human breast specimens with ductal carcinoma in-situ. We assessed image quality of both setups and compared it to histology. We showed that both setups made it possible to target internal features of breast specimens with better resolution and contrast than previously achieved, demonstrating that grating-based phase-contrast X-ray CT could be a complementary tool for clinical histopathology. [ABSTRACT FROM AUTHOR]

Organ biobanking is the pending subject of cryopreservation. Although the problem is multifaceted, advances in recent decades have largely related it to achieving rapid and uniform rewarming of cryopreserved samples. This is a physical challenge largely investigated in past in addition to cryoprotectant toxicity studies, which have also shown a great amount of advancement. This paper presents a proof-of-principle, based on the nematode Caenorhabditis elegans, of a technology capable of performing such a function: high intensity focused ultrasound. Thus, avoiding the problem of recrystallization, this worm, in its adult state, preserved at − 80 ∘ C , has been systematically brought back to life after being heated with High Intensity Focused Ultrasound (HIFU) waves. The great advantage of this technology is that it is scalable; in addition, rewarming can be monitored in real time by MRI thermography and can be controlled by acoustic interferometry. We anticipate that our findings are the starting point for a possible approach to rewarming that can be used for cryopreservation of millimeter scale systems: either alone or in combination with other promising ways of heating, like nanowarming or dielectric heating, the present technology provides new ways of solving the physical aspects of the problem of recrystallization in cryopreservation, opening the door for the long-term storage of larger samples. [ABSTRACT FROM AUTHOR]

In optical coherence tomography (OCT), there is a trade-off between the scanning time and image quality, leading to a scarcity of high quality data. OCT platforms provide different scanning presets, producing visually distinct images, limiting their compatibility. In this work, a fully automatic methodology for the unpaired visual conversion of the two most prevalent scanning presets is proposed. Using contrastive unpaired translation generative adversarial architectures, low quality images acquired with the faster Macular Cube preset can be converted to the visual style of high visibility Seven Lines scans and vice-versa. This modifies the visual appearance of the OCT images generated by each preset while preserving natural tissue structure. The quality of original and synthetic generated images was compared using brisque. The synthetic generated images achieved very similar scores to original images of their target preset. The generative models were validated in automatic and expert separability tests. These models demonstrated they were able to replicate the genuine look of the original images. This methodology has the potential to create multi-preset datasets with which to train robust computer-aided diagnosis systems by exposing them to the visual features of different presets they may encounter in real clinical scenarios without having to obtain additional data. [ABSTRACT FROM AUTHOR]

A novel hybrid multimode interferometer for sensing applications operating with both TE and TM polarizations simultaneously is proposed and numerically demonstrated. The simulations were performed assuming an operating wavelength of 633 nm with the goal of future use as a biosensor, but its applications extend beyond that area and could be adapted for any wavelength or application of interest. By designing the mutimode waveguide core with a low aspect ratio, the confinement characteristics of TE modes and TM modes become very distinct and their interaction with the sample in the sensing area becomes very different as well, resulting in high device sensitivity. In addition, an excitation structure is presented, that allows good control over power distribution between the desired modes while also restricting the power coupled to other undesired modes. This new hybrid TE/TM approach produced a bulk sensitivity per sensor length of 1.798 rad · RIU - 1 · μ m - 1 and a bulk sensitivity per sensor area of 2.140 rad · RIU - 1 · μ m - 2 , which represents a much smaller footprint when compared to other MMI sensors, contributing to a higher level of integration, while also opening possibilities for a new range of MMI devices. [ABSTRACT FROM AUTHOR]

We study the improvement in the phase sensitivity of a Mach–Zehnder interferometer (MZI) using the superposition of 'Schrödinger's cat-like state with the vacuum state (SCVS)' and the vacuum state as inputs. With this setup, we examine the effect on the phase sensitivity of the interferometer using a parity detection scheme. We find better phase sensitivity under some conditions for this setup having potential application in quantum sensing. [ABSTRACT FROM AUTHOR]

The correct absolute time of a seismogram is an important prerequisite for many seismological processing methods. Recently, seismic interferometry has been applied to continuously estimate instrumental clock errors in certain regions. However, previous studies have focused on estimating clock errors in only one target region for each study, and data processing methods that provide more stable results in different regions have not been explored. This study presents a new method to estimate clock errors that are more stable in various regions based on seismic interferometry with windowed cross-correlation and least absolute deviation regression. The applicability of this method was validated by its application to 50 active volcanoes in Japan. We found clock errors at 23 stations at 13 volcanoes between January 2017 and December 2021. The maximum amplitude of the clock errors ranged between 0.24 and 18.27 s. This value range is significantly larger than the amplitude of the background fluctuation in the estimated values of clock errors, which is less than 0.05 s for most volcanoes. A comparison of different approaches for the estimation of clock error shows that our proposed method that uses windowed cross-correlation and least absolute deviation regression can reduce the effect of waveform changes in seismic ambient noise cross-correlation functions, probably because of noise source fluctuations. Managing the time stamps of data using the method proposed in this study will contribute to data quality assurance and ensure the reliability of analysis using time information in various study regions. [ABSTRACT FROM AUTHOR]

Optical interferometry-based techniques are ubiquitous in various measurement, imaging, calibration, metrological, and astronomical applications. Repeatability, simplicity, and reliability of measurements have ensured that interferometry in its various forms remains popular—and in fact continues to grow—in almost every branch of measurement science. In this paper, we propose a novel actively-controlled optical interferometer in the Twyman–Green configuration. The active beam control within the interferometer is a result of using an actively-controlled tunable focus lens in the sample arm of the interferometer. This innovation allows us to characterize transparent samples cut in the cubical geometry without the need for bulk mechanical motion within the interferometer. Unlike thickness/refractive index measurements with conventional Twyman–Green interferometers, the actively-tunable interferometer enables bulk-motion free thickness or refractive index sample measurements. With experimental demonstrations, we show excellent results for various samples that we characterized. The elimination of bulk motion from the measurement process promises to enable miniaturization of actively-tunable Twyman–Green interferometers for various applications. [ABSTRACT FROM AUTHOR]

When studying the optical properties of thin films, in order to obtain reliable information about the magnitude of their optical constants, it is necessary to accurately measure the thickness of the metal. Thickness 600 < d < 1500 Å is measured by the method of multibeam interferometry and the resonant-frequency method. [ABSTRACT FROM AUTHOR]