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Herein, we reported novel Y4GeO8:Er3+,Yb3+ phosphors elaborated via conventional solid-state reaction, and we further explored their properties as optical thermometer by using fluorescence intensity ratio (FIR) method complemented by detailed analysis on crystal structure, up-conversion luminescence and energy transfer from Yb3+ to Er3+. Upon 980 nm laser excitation, Y4GeO8:Er3+,Yb3+ phosphors present 525, 547 and 659 nm emission bands assigned to the characteristic transitions of Er3+. Furthermore, Y4GeO8:Er3+,Yb3+ samples show outstanding temperature sensing performances. To be specific, the minimal temperature resolution is 0.03 K (303 K), and the relative sensitivity of FIR can be up to 1.152%/K (303 K). Hence, Y4GeO8:Er3+,Yb3+ phosphors can be possible candidates for thermometry devices.

Background Preserving the cellular structure at the highest possible resolution is a prerequisite for morphological studies to deepen our understanding of cellular functions. A revival of interest in rapid-freezing methods combined with breaking-open techniques has taken place with the development of effective and informative approaches in platinum replica electron microscopy, thus providing new approaches to address unresolved issues in cell biology. Highlight The images produced with platinum replicas revealed 3D structures of the cell interior: (1) cell membranes associated with highly organized cytoskeletons, including podosomes or geodomes, (2) heterogeneous clathrin assemblies and membrane skeletons on the inner side of the membrane, and (3) organization of the cytoskeleton after detergent extraction. Conclusion In this review, I will focus on the platinum replica method after brokenopen cells have been broken open with mechanical shearing or detergent extraction. Often forgotten nowadays is the use of platinum replicas with stereomicroscopic observations for transmission electron microscopy study; these “old-fashioned” imaging techniques, combined with the breaking-open technique represent a highly informative approach to deepen our understanding of the organization of the cell interior. These are still being pursued to answer outstanding biological questions.

Huntingtin-associated protein 1 (HAP1) is abundantly expressed in the neurons of the central nervous system and forms unique intracytoplasmic inclusions of unknown function called ‘stigmoid bodies’ (STBs). Transmission electron microscopy has revealed that the STBs are aggregates of granules containing cavities with a diameter of 0.5–3 µm. Small STBs fuse to form larger STBs, the size of which is said to vary depending on the developmental growth stage and brain region. Light microscopy can only reveal that these STBs have similar circular shapes due to its limited resolution. Therefore, light microscopy is only fit for the study of the STB distribution and quantitative changes. We, herein, suggest the adoption of correlative light and electron microscopy, which combines confocal laser scanning microscopy and scanning electron microscopy as the method allowing us to identify the huntingtin-associated protein 1–positive STBs in formalin-fixed paraffin-embedded (FFPE) sections. This approach allows us to study the three-dimensional morphology of immunolabeled objects in histopathological specimens. The STBs in FFPE sections of murine hypothalami reflected the transmission electron microscopic images of Epon-embedded STBs, although we were not able to observe any organelle covering the STBs of the FFPE sections. Furthermore, we were able to reconstruct the three-dimensional structure of the STB, and we identified it to be of spherical form, covered with mitochondria and rough endoplasmic reticulum, and bearing a cluster of cavities in the centre. In the future, we might gain new insights by comparing the three-dimensional structure of the STB between different neurons and under a variety of conditions.

Micropipette aspiration (MPA) is an essential tool in mechanobiology; however, its potential is far from fully exploited. The traditional MPA technique has limited temporal and spatial resolution and requires extensive post processing to obtain the mechanical fingerprints of samples. Here, we develop a MPA system that measures pressure and displacement in real time with sub-nanometer resolution thanks to an interferometric readout. This highly sensitive MPA system enables studying the nanoscale behavior of soft biomaterials under tension and their frequency-dependent viscoelastic response., Beradi et al. establish a micropipette aspiration platform which enables sensitive real-time viscoelastic measurements of soft biomaterials. They use it to characterize the rheological behavior of cells and soft materials at very small deformations, yielding consistent and reproducible values.

An adequate representation of the interaction between the land surface and the atmosphere is critical for both numerical weather prediction and climate models. The surface energy and mass balances are tightly coupled to the terrestrial water cycle, mainly through the state of soil moisture. An inadequate representation of the terrestrial water cycle will deteriorate the state of the land surface model and introduce biases to the atmospheric model. The validation of land surface models is challenging, as there are very few observations and the soil is highly heterogeneous. In this paper, a validation framework for land surface schemes based on catchment mass balances is presented. The main focus of our development lies in the application to kilometer-resolution numerical weather prediction and climate models, although the approach is scalable in both space and time. The methodology combines information from multiple observation-based datasets. Observational uncertainties are estimated by using independent sets of observations. It is shown that the combination of observation-based datasets and river discharge measurements close the water balance fairly well for the chosen catchments. As a showcase application, the framework is then applied to compare and validate four different versions of TERRA ML, the land surface scheme of the COSMO numerical weather prediction and climate model over five mesoscale catchments in Switzerland ranging from 105 to 1713 km2. Despite large observational uncertainties, validation results clearly suggest that errors in terrestrial storage changes are closely linked to errors in runoff generation and emphasize the crucial role of infiltration processes.

Super‐resolution fluorescence imaging provides critically improved information about the composition, organization, and dynamics of subcellular structures. Quantum dot triexciton imaging (QDTI) has been introduced as an easy‐to‐use sub‐diffraction imaging method that achieves an almost 2‐fold improvement in resolution when used with conventional confocal microscopes. Here, we report an overall 3‐fold increase in lateral and axial resolution compared to conventional confocal microscopes by combining QDTI with state‐of‐the‐art commercial laser scanning microscope systems., We report an overall 3‐fold increase in lateral and axial image resolution for confocal fluorescence microscopy by combining quantum dot triexciton imaging with state‐of‐the‐art commercial laser scanning microscope systems. Based on quantum dots as fluorescent labels, we present an easy‐to‐use super‐resolution method. A single confocal scan with minimal image post‐processing is sufficient to produce a sub‐diffraction image with an image resolution of approx. 80 nm lateral and 200 nm axial.

The use of very high-resolution digital pulse width modulators (DPWMs) for high frequency dc–dc converters has been steadily increasing in recent years. However, the resolution of the DPWM formed by counters and comparators is limited when the switching frequency rise above MHz range. Given this limitation, new strategies for DPWM architectures are being designed to increase the resolution of the signals. This article proposes two new DPWMs architectures with the aim of increasing the resolution of trigger signals using field programmable gate arrays (FPGAs). The first proposed architecture is a hybrid DPWM, which integrates a clock manager and a delay line. For this architecture, the delay line is configured using FPGA intellectual properties (IP) blocks. This delay stage allows a fine resolution in the picosecond scale. In addition, an alternative solution has been implemented to generate two signals, the main signal and its complementary one, including high resolution for the dead time, which is also configurable. Both architectures have been tested through static and dynamic tests on two FPGAs of different costs, an Artix-7 (low-cost) and a Kintex-UltraScale 7 (high-cost) by Xilinx.

The pursuit of low power consumption, high charge collection efficiency (CCE), and high energy resolution is critical for the development of high performance GaN-based alpha-particle detectors. In this letter, we fabricated a low-voltage p-i-n GaN-based alpha-particle detector with superior energy resolution. The detector exhibits a very low leakage current of pA level even at −100 V and high CCEs of 31% and 92% at zero bias and reverse bias of 50 V, respectively. Meanwhile, the detector demonstrates a high energy resolution of 2.48% at −20 V. These excellent performances are attributed to the artificially enlarged path of alpha particles in the depletion region by employing the angular incidence measurement method and the high crystal quality of the epitaxial film grown on a single-crystal GaN substrate. In addition, the damage events caused by the alpha particles are also investigated using the Monte Carlo calculation. These results are anticipated to promote the research of radiation-hardened GaN-based detectors.

This work revisits the Gilbert–Johnson–Keerthi (GJK) and the radial direction-based shape erosion method for the contact resolution of non-spherical particles in discrete element method (DEM). Tests on single contact indicate that the shape erosion would frequently lead to an overestimation on contact overlap, but has a minor effect on contact normal and contact point. The undesired effect of shape erosion on contact overlap is more pronounced for small overlaps and elongated particles. Further study based on random packing and triaxial compression tests suggests that the shape erosion has a dominant effect on the weak contacts within the packing. The overestimation of contact overlaps due to shape erosion may tend to push particles away, thereby dismiss the weak contacts and result in an overall smaller coordination number. Nonetheless, as the contribution of weak contacts to particle shear resistance is relatively small, the shape erosion exhibits negligible effects on the packing fabric and the stress–strain behaviors. In practice, it is suggested that the erosion ratio should be carefully set such that it is compatible (e.g., in a similar order of magnitude) to the overlaps of strong contacts.

We evaluate existing spike sorters and present a new one that resolves many sorting challenges. The new sorter, called “full binary pursuit” or FBP, comprises multiple steps. First, it thresholds and clusters to identify the waveforms of all unique neurons in the recording. Second, it uses greedy binary pursuit to optimally assign all the spike events in the original voltages to separable neurons. Third, it resolves spike events that are described more accurately as the superposition of spikes from two other neurons. Fourth, it resolves situations where the recorded neurons drift in amplitude or across electrode contacts during a long recording session. Comparison with other sorters on ground-truth data sets reveals many of the failure modes of spike sorting. We examine overall spike sorter performance in ground-truth data sets and suggest postsorting analyses that can improve the veracity of neural analyses by minimizing the intrusion of failure modes into analysis and interpretation of neural data. Our analysis reveals the tradeoff between the number of channels a sorter can process, speed of sorting, and some of the failure modes of spike sorting. FBP works best on data from 32 channels or fewer. It trades speed and number of channels for avoidance of specific failure modes that would be challenges for some use cases. We conclude that all spike sorting algorithms studied have advantages and shortcomings, and the appropriate use of a spike sorter requires a detailed assessment of the data being sorted and the experimental goals for analyses. NEW & NOTEWORTHY Electrophysiological recordings from multiple neurons across multiple channels pose great difficulty for spike sorting of single neurons. We propose methods that improve the ability to determine the number of individual neurons present in a recording and resolve near-simultaneous spike events from single neurons. We use ground-truth data sets to demonstrate the pros and cons of several current sorting algorithms and suggest strategies for determining the accuracy of spike sorting when ground-truth data are not available.

The paper presents an analytical model describing the dynamics of ion cloud, taking into account the action of space charge during a motion in ion mobility spectrometer — starting from the reaction region, where the shutter forms an ion pulse, and the further drift of the formed ion pulse towards the collector. The presented model lets to estimate the degree of influence of the space charge on possible ion losses and the resolution of ion mobility spectrometer. The effect of the space charge becomes noticeable, starting with the ion density of 106 cm–3. Comparison of the results obtained using the analytical model with the results of numerical solution of the initial equations shows that they practically coincide.

Статья посвящена рассмотрению особенностей и формулированию практических рекомендаций по разрешению иерархических юридических коллизий в российском праве. Автор статьи предлагает трактовать иерархическую (субординационную) юридическую коллизию расширительно: не только как противоречие между двумя или более нормативно-правовыми актами, но и как возможное противоречие между правовыми актами разных типов, включая правоприменительные (индивидуальные) и интерпретационные акты. Подчеркивается, что базовым правилом разрешения любой иерархической юридической коллизии должно быть правило юридической силы. В то же время в настоящий момент в российском праве нормы, определяющие данное понятие, а равно устанавливающие четкие механизмы преодоления юридических коллизий, включая иерархические, отсутствуют. Под юридической силой предлагается понимать особое свойство правовых актов, благодаря наличию которого данные акты формируют иерархию, и нижестоящие акты вышестоящим противоречить не могут. Выдвигается тезис о том, что не типичные иерархические коллизии в праве (коллизии между нормативно-правовым актом, с одной стороны, и правоприменительным или интерпретационным актом, с другой, а равно несколькими правоприменительными и (или) интерпретационными актами между собой) как разновидность иерархической юридической коллизии должны разрешаться с обязательным использованием правила юридической силы. То есть акты нормативного толкования и правоприменения должны быть приравнены по юридической силе к интерпретируемым и применяемым актам. Именно такой путь позволит избежать остановок в работе механизма реализации права, которых, как известно, современное правовое государство позволить себе не может. The article is devoted to the consideration of the features and the development of practical recommendations for resolving hierarchical legal collisions in Russian law. The author of the article proposes to interpret the hierarchical legal collision broadly, not only as a contradiction between regulatory legal acts, but also as a possible contradiction between legal acts of different types. It is emphasized that the basic rule for resolving any hierarchical legal collision should be the rule of legal force. However, at the moment in Russian law there are no norms defining this concept, as well as establishing clear mechanisms for overcoming legal conflicts, including hierarchical ones. It is proposed to understand legal force as a special property of legal acts, due to the presence of which these acts form a hierarchy, and lower-level acts cannot contradict higher-level ones. The thesis is put forward that non-typical hierarchical collisions in law should also be resolved with the obligatory use of the rule of legal force. This means that the acts of normative interpretation and law enforcement should be equated in legal force with the interpreted and applied acts. This is the way to avoid stoppages in the work of the mechanism for the implementation of the law, which, as you know, the modern constitutional state cannot afford.

The weak X-ray capture capability of organic scintillators always leads to poor imaging resolution and detection sensitivity. Here, we realize an efficient and reabsorption-free organic scintillato...

Confocal microscopy1 remains a major workhorse in biomedical optical microscopy owing to its reliability and flexibility in imaging various samples, but suffers from substantial point spread function anisotropy, diffraction-limited resolution, depth-dependent degradation in scattering samples and volumetric bleaching2. Here we address these problems, enhancing confocal microscopy performance from the sub-micrometre to millimetre spatial scale and the millisecond to hour temporal scale, improving both lateral and axial resolution more than twofold while simultaneously reducing phototoxicity. We achieve these gains using an integrated, four-pronged approach: (1) developing compact line scanners that enable sensitive, rapid, diffraction-limited imaging over large areas; (2) combining line-scanning with multiview imaging, developing reconstruction algorithms that improve resolution isotropy and recover signal otherwise lost to scattering; (3) adapting techniques from structured illumination microscopy, achieving super-resolution imaging in densely labelled, thick samples; (4) synergizing deep learning with these advances, further improving imaging speed, resolution and duration. We demonstrate these capabilities on more than 20 distinct fixed and live samples, including protein distributions in single cells; nuclei and developing neurons in Caenorhabditis elegans embryos, larvae and adults; myoblasts in imaginal disks of Drosophila wings; and mouse renal, oesophageal, cardiac and brain tissues. A combination of multiview imaging, structured illumination, reconstruction algorithms and deep-learning predictions realizes spatial- and temporal-resolution improvements in fluorescence microscopy to produce super-resolution images from diffraction-limited input images.

In Taiwan, the heat island effect is the most significant in Taipei City. Thus this research provides a causal explanation for why urban outdoor air temperature has an M-shape EKC pattern for metropolitan areas in a country. Results show that the growth rate change in CO2 concentration can induce changes to the periods of the La Nino effect and EI Nino effect, causing high fluctuations in rain accumulation. The amount of rain then alters A-type evaporation, and so the evaporation amount is the top factor for the diffusion of a city’s heat. This fluctuation plays as a cooling and heating source for the V region of the M shape in the outdoor air temperature EKC pattern. In our previous studies, the growth rate change in CO2 concentration correlates to the energy structure. Therefore, a heat sinking model has been proposed to explain the accumulation of heat in a city, in which a proportion process for the solar irradiation source from buildings and remodeling engineering from a public housing policy and the private sector can play as a heating source of the two peaks of the M shape and present long-term linear growth in the outdoor air temperature EKC pattern.

This paper reports on gas sensing based on near-infrared (NIR) reconstructive spectroscopy using a surface plasmon resonance (SPR) photodetector. The reconstructive spectrometer consists of an Au g...

The electrical double layer (EDL) at solid-liquid interfaces is key to interfacial transport and reaction processes and numerous emerging applications exploiting such processes. Herein, by studying hysteresis ion-transport processes in nanopipettes near charged substrates, we found the resulting cross-point potential (Vcp) to represent the surface potential of both nanopipettes and substrates. After the subtraction of Vcp in bulk solution, the remaining ΔVcp shows excellent exponential decay with respect to the separation distance from the substrates and agrees very well with the classical double-layer theory. The revealed new hysteresis ion transport in nanopipettes would provide a new way for the simple and direct EDL imaging of various interfaces of interest with nanoscale resolution in scanning ion conductance microscopy.

A user-friendly Python-based program has been developed to analyze diffuse scattering from single crystals with the reverse Monte Carlo method. The approach allows for refinement of correlated disorder from atomistic supercells with magnetic or structural (occupational and/or displacive) disorder., A user-friendly program has been developed to analyze diffuse scattering from single crystals with the reverse Monte Carlo method. The approach allows for refinement of correlated disorder from atomistic supercells with magnetic or structural (occupational and/or displacive) disorder. The program is written in Python and optimized for performance and efficiency. Refinements of two user cases obtained with legacy neutron-scattering data demonstrate the effectiveness of the approach and the developed program. It is shown with bixbyite, a naturally occurring magnetic mineral, that the calculated three-dimensional spin-pair correlations are resolved with finer real-space resolution compared with the pair distribution function calculated directly from the reciprocal-space pattern. With the triangular lattice Ba3Co2O6(CO3)0.7, refinements of occupational and displacive disorder are combined to extract the one-dimensional intra-chain correlations of carbonate molecules that move toward neighboring vacant sites to accommodate strain induced by electrostatic interactions. The program is packaged with a graphical user interface and extensible to serve the needs of single-crystal diffractometer instruments that collect diffuse-scattering data.

PURPOSE Detectors for positron emission tomography (PET) typically use two types of scintillation crystals, pixelated or monolithic. A variant of these types of scintillators are the so-called semi-monolithic crystals. They consist of a monolithic crystal segmented in one direction in pieces called slabs. These scintillators have the potential to successfully combine the benefits of pixelated and monolithic configurations, providing good timing and spatial resolutions as well as the capacity to decode the depth of interaction (DOI) information. In this work, the timing performance of a detector based on semi-monolithic crystals was studied in depth. The energy response was also evaluated. METHODS The semi-monolithic detector consists of 1 × 24 LYSO slabs of 25.4 × 12 × 0.95 mm3 each. The bottom surface of the slabs is coupled to an array of 8 × 8 silicon photomultipliers (SiPMs) of 3 × 3 mm2 active area, 50 μm cell size and 3.2 mm pitch. The 64 output signals were independently readout by the TOFPET2 ASIC. In order to achieve the best coincidence time resolution (CTR), four different time walk corrections were tested. Additional work investigated the best method of combining the timestamps belonging to the same event. RESULTS The resolvability of the slabs in the measured flood maps improves with the thickness of a light guide placed in between the scintillators and photosensors. The energy resolution does not change significantly with values as good as 13.7%. Regarding the CTR, values of 335.8, 363, 369.8, and 402.5 ps have been obtained for the whole detector for no light guide, 0.5, 1.0, and 1.5 mm thickness light guide cases, respectively. These values further improve to 276.1, 302.6, 305.6 and 336.2 ps, respectively, when energy-weighted averaging of timestamps is applied. CONCLUSIONS We have shown both an excellent timing resolution and good energy resolution for a PET detector based on semi-monolithic crystals. The use of light guides of different thicknesses does not significantly affect the energy resolution of the whole detector, but the timing capabilities slightly worsen with the increasing thickness of the light guide.

Herein, we present the initial steps toward developing a framework that will enable the characterization of photoinitiated dynamics within large molecular ions in the gas phase with temporal and energy resolution. We combine the established techniques of tag-loss action spectroscopy on cryogenically trapped molecular ions with ultrafast vibrational spectroscopy by measuring the linear action spectrum of N2-tagged protonated diglycine (GlyGlyH+·N2) with an ultrafast infrared (IR) pulse pair. The presented time-domain data demonstrate that the excited-state vibrational populations in the tagged parent ions are modulated by the ultrafast IR pulse pair and encoded through the messenger tag-loss action response. The Fourier transform of the time-domain action interferograms yields the linear frequency-domain vibrational spectrum of the ion ensemble, and we show that this spectrum matches the linear spectrum collected in a traditional manner using a frequency-resolved IR laser. Time- and frequency-domain interpretations of the data are considered and discussed. Finally, we demonstrate the acquisition of nonlinear signals through cross-polarization pump-probe experiments. These results validate the prerequisite first steps of combining tag-loss action spectroscopy with two-dimensional IR spectroscopy for probing dynamics in gas-phase molecular ions.

Land surface heterogeneity exerts a strong control on atmospheric boundary-layer (ABL) evolution by spatially varying the distribution and partitioning of surface energy fluxes and triggering secondary circulations. The representation of this physical process in numerical weather prediction (NWP) models is especially affected in the terra incognita as the model grid resolution approaches the length-scale of the largest eddies in the boundary layer. We explore these effects for a mesoscale strip-like land surface inhomogeneity in land cover, soil moisture or a superposition of both embedded in an elsewhere homogeneous landscape. The study is conducted with the numerical weather prediction model ICON (ICOsahedral Nonhydrostatic), using the default operational level 2.5 Mellor–Yamada turbulence closure (MY) and a large-eddy simulation (LES) configuration as a benchmark. While simulations with the default ABL scheme approach the LES reference when refining the spatial grid towards finer resolution, the model generates artificial circulations leading to ABL height oscillations when the horizontal grid resolution (∆𝑥) approaches the ABL height (𝑧𝑖). The effect of these model-induced circulations on the state of the boundary layer is even present with weak thermal heterogeneity (∆𝐻) under low background wind speed (𝑣𝑥) but diminishes with increasing background wind speed. The tuning of the asymptotic turbulent mixing length-scale (𝑙∞) in the operational ABL scheme helps in reducing the amplitude of the oscillations, thereby reducing the artificially induced circulations due to thermal heterogeneity which might act as unintentional trigger for clouds and precipitation. Based on the tuned synthetic model data from sensitivity runs, we propose a new parametrization for a 2-D 𝑙∞ as a function of ∆𝐻, 𝑧𝑖/∆𝑥 and 𝑣𝑥, which is otherwise held as a constant in the ABL scheme.

Scalable synthesis of two-dimensional gallium (2D-Ga) covered by graphene layers was recently realized through confinement heteroepitaxy using silicon carbide substrates. However, the thickness, uniformity, and area coverage of the 2D-Ga heterostructures have not previously been studied with high-spatial resolution techniques. In this work, we resolve and measure the 2D-Ga heterostructure thicknesses using scanning electron microscopy (SEM). Utilizing multiple correlative methods, we find that SEM image contrast is directly related to the presence of uniform bilayer Ga at the interface and a variation of the number of graphene layers. We also investigate the origin of SEM contrast using both experimental measurements and theoretical calculations of the surface potentials. We find that a carbon buffer layer is detached due to the gallium intercalation, which increases the surface potential as an indication of the 2D-Ga presence. We then scale up the heterostructure characterization over a few-square millimeter area by segmenting SEM images, each acquired with nanometer-scale in-plane resolution. This work leverages the spectroscopic imaging capabilities of SEM that allows high-spatial resolution imaging for tracking intercalants, identifying relative surface potentials, determining the number of 2D layers, and further characterizing scalability and uniformity of low-dimensional materials.

The performance of CZT in $$\gamma $$ -ray and X-ray detection is growing rapidly in these years. However, there are only a few reports on its utilization in $$\alpha $$ particle detection. Therefore, to study the properties of CZT for detection of $$\alpha $$ particle, a detection system has been manufactured, and a series of simulations have been done. A $$22\times 22\times 0.7 mm^3$$ planar CZT detector is deployed to detect the $$\alpha $$ particles from a radiation source containing Am-241 and Pu-239, while COMSOL MultiPhysics and GEANT4 are employed in the simulation of charge collection and interaction between $$\alpha $$ particles and CZT. An energy resolution of 1.47% FWHM at 5.486MeV and 1.32% at 5.157MeV has been achieved. A simulated spectrum has been created, and it is analogous to the one from experiment. The experiment results show the potential of CZT in $$\alpha $$ detection. The simulations are confirmed effective and will guide a better design of the detecting system.

A main determinant of the spatial resolution of live-cell super-resolution (SR) microscopes is the maximum photon flux that can be collected. To further increase the effective resolution for a given photon flux, we take advantage of a priori knowledge about the sparsity and continuity of biological structures to develop a deconvolution algorithm that increases the resolution of SR microscopes nearly twofold. Our method, sparse structured illumination microscopy (Sparse-SIM), achieves ~60-nm resolution at a frame rate of up to 564 Hz, allowing it to resolve intricate structures, including small vesicular fusion pores, ring-shaped nuclear pores formed by nucleoporins and relative movements of inner and outer mitochondrial membranes in live cells. Sparse deconvolution can also be used to increase the three-dimensional resolution of spinning-disc confocal-based SIM, even at low signal-to-noise ratios, which allows four-color, three-dimensional live-cell SR imaging at ~90-nm resolution. Overall, sparse deconvolution will be useful to increase the spatiotemporal resolution of live-cell fluorescence microscopy. The resolution of fluorescence microscopy is increased by incorporating prior information into deconvolution algorithms.

Actophorin, a protein that severs actin filaments isolated from the amoeba Acanthamoeba castellanii, was employed as a test case for crystallization under microgravity. Crystals of purified actophorin were grown under microgravity conditions aboard the International Space Station (ISS) utilizing an interactive crystallization setup between the ISS crew and ground-based experimenters. Crystals grew in conditions similar to those grown on earth. The structure was solved by molecular replacement at a resolution of 1.65 Å. Surprisingly, the structure reveals conformational changes in a remote β-turn region that were previously associated with actophorin phosphorylated at the terminal residue Ser1. Although crystallization under microgravity did not yield a higher resolution than crystals grown under typical laboratory conditions, the conformation of actophorin obtained from solving the structure suggests greater flexibility in the actophorin β-turn than previously appreciated and may be beneficial for the binding of actophorin to actin filaments.

We propose an end‐to‐end neural coreference resolution for the Korean language that uses an attention mechanism to point to the same entity. Because Korean is a head‐final language, we focused on a method that uses a pointer network based on the head. The key idea is to consider all nouns in the document as candidates based on the head‐final characteristics of the Korean language and learn distributions over the referenced entity positions for each noun. Given the recent success of applications using bidirectional encoder representation from transformer (BERT) in natural language‐processing tasks, we employed BERT in the proposed model to create word representations based on contextual information. The experimental results indicated that the proposed model achieved state‐of‐the‐art performance in Korean language coreference resolution.

The objective of the present study is to systematically quantify the along-track resolution of Satellite for Argos and AltiKa (SARAL)/AltiKa and Environmental Satellite (ENVISAT)-RA2 altimeters over continental margins. Spectral coherence and power spectral density estimated from pairs of stacked (averaged) sea surface height (SSH) profiles from repeat tracks as a function of wave number are used to estimate along-track resolution and noise characteristics, respectively. The analyses were carried out along 96 SARAL/AltiKa and ENIVISAT-RA2 tracks covering continental margins of India, Gulf of Mexico, and South America. Our study clearly suggests that for all three sites the short-wavelength resolution of SARAL/AltiKa (15���18 km) is ~27���33% better than ENVISAT-RA2 (22���25 km) data. Variations in sediment thickness along the continental margins have significant influence in the along-track resolution of both altimeters. Strong geoid signals owing to thin sediments (0.1���0.3 km thick) along the South American margin provided higher resolution for both SARAL/AltiKa (15 km) and ENVISAT-RA2 (22 km) altimeters. Conversely, over the continental margins of India and Gulf of Mexico with huge sediment thickness (1���20 km), the resolution of SARAL/AltiKa and ENVISAT-RA2 drops to 18 and 25 km, respectively. We also observe that resolution of both altimeters is higher by 1���2 km for continental margins with narrow shelf. The present study has implications in the generation of high-resolution marine geoid and gravity anomalies using SARAL/AltiKa along with other altimeters.

The size tunability and chemical versatility of nanostructures enable electron sources of high brightness and temporal coherence, both of which are important characteristics for high-resolution electron microscopy1–3. Despite intensive research efforts in the field, so far, only conventional field emitters based on a bulk tungsten (W) needle have been able to yield atomic-resolution images. The absence of viable alternatives is in part caused by insufficient fabrication precision for nanostructured sources, which require an alignment precision of subdegree angular deviation of a nanometre-sized emission area with the macroscopic emitter axis4. To overcome this challenge, in this work we micro-engineered a LaB6 nanowire-based electron source that emitted a highly collimated electron beam with good lateral and angular alignment. We integrated a passive collimator structure into the support needle tip for the LaB6 nanowire emitter. The collimator formed an axially symmetric electric field around the emission tip of the nanowire. Furthermore, by means of micromanipulation, the support needle tip was bent to align the emitted electron beam with the emitter axis. After installation in an aberration-corrected transmission electron microscope, we characterized the performance of the electron source in a vacuum of 10−8 Pa and achieved atomic resolution in both broad-beam and probe-forming modes at 60 kV beam energy. The natural, unmonochromated 0.20 eV electron energy loss spectroscopy resolution, 20% probe-forming efficiency and 0.4% probe current peak-to-peak noise ratio paired with modest vacuum requirements make the LaB6 nanowire-based electron source an attractive alternative to the standard W-based sources for low-cost electron beam instruments. So far, only conventional field emitters based on a bulk W needle have achieved atomic resolution in electron microscopy. Here, through the integration of a passive collimator structure and micromanipulation-based alignment of the support needle, a LaB6 nanowire emitter yields stable emission under moderate vacuum conditions and allows for atomic-resolution images and high energy resolution.

How to quantify local axonal orientations Mapping the axonal trajectories of the brain’s white matter at cellular resolution is a long-standing goal of neuroscience. However, existing methods for mapping the axons are either limited to animal studies or require highly specialized equipment for data acquisition and processing. Nissl staining identifies cell nuclei and has been used extensively to investigate parcellations of the cortical gray matter, but the white matter has largely been neglected with this technique. Schurr and Mezer now show that Nissl staining, together with structure tensor analysis, can be used to study white matter architecture and the organization of the glial cell framework around axons over the whole brain. This technique greatly advances our knowledge regarding the organization of glial cells and the fine-grained organization of axonal projections in the brain. —PRS

A standard digital rock physics workflow aims to simulate petrophysical properties of rock samples using few millimeter size subsets scanned with X-ray microtomography at a high resolution of around 1 μm. The workflow is mainly based on image analysis and simulation procedures at a subset scale leading to potential uncertainties and errors that cannot be quantified experimentally. To overcome the gap between scales, we propose to integrate three-dimensional (3D) printing technology to generate enlarged subsets at a scale where experimental measurements are feasible to validate simulated results. In this study, we 3D printed synthetic and real samples and compared digital and experimental rock properties. The most challenging phase in the workflow consists of the difficulties encountered while cleaning the 3D printed samples to remove the support material. Results for subsets extracted from synthetic, sandstone, and carbonate samples showed good agreement between digital and experimental measurements for porosity values less than 12% and a range of permeability values between 100 and 2000 mD.

In this study, 3″ × 3″ NaI(Tl) detector, which is widely used in gamma spectroscopy, was modeled with FLUKA code, and calculations required to determine the detector's energy resolution were reported. Photon beams with isotropic distribution with 59, 81, 302, 356, 511, 662, 835, 1173, 1275, and 1332 keV energy were used as radiation sources. The photon pulse height distribution of the NaI(Tl) without influence of its energy resolution obtained with FLUKA code has been converted into a real NaI(Tl) response function, using the necessary conversion process. The photon pulse height distribution simulated in the conversion process was analyzed using the ROOT data analysis framework. The statistical errors of the simulated data were found in the range of 0.2–1.1%. When the results, obtained with FLUKA and ROOT, are compared with the literature data, it is seen that the results are in good agreement with them. Thus, the applicability of this procedure has been demonstrated for the other energy values mentioned.

Studying neuronal activity at synapses requires high spatiotemporal resolution. For high spatial resolution in vivo imaging at depth, adaptive optics (AO) is required to correct sample-induced aberrations. To improve temporal resolution, Bessel focus has been combined with two-photon fluorescence microscopy (2PFM) for fast volumetric imaging at subcellular lateral resolution. To achieve both high-spatial and high-temporal resolution at depth, we develop an efficient AO method that corrects the distorted wavefront of Bessel focus at the objective focal plane and recovers diffraction-limited imaging performance. Applying AO Bessel focus scanning 2PFM to volumetric imaging of zebrafish larval and mouse brains down to 500 µm depth, we demonstrate substantial improvements in the sensitivity and resolution of structural and functional measurements of synapses in vivo. This enables volumetric measurements of synaptic calcium and glutamate activity at high accuracy, including the simultaneous recording of glutamate activity of apical and basal dendritic spines in the mouse cortex., Adaptive optics (AO) corrects sample aberrations and allows high spatial resolution at depth in vivo. Here the authors report an AO method for Bessel focus; they apply AO Bessel focus scanning fluorescence microscopy to volumetric imaging and measure synaptic calcium and glutamate activity in vivo.

In this paper, we demonstrate the optimal multi-modes for glucose droplet (GD) sensing depending on sample (glucose droplet) positions in a half-wavelength ( $\lambda $ /2) microstrip resonator. Using two different GD positions, i.e., an edge and a center position, in the resonator, the resonant behavior of microwave multi-modes for GD sensing was investigated. GDs with three different concentrations, i.e., 0.1, 0.2, and 0.3 g/ml, were tested in the present experiment. With increasing GD concentration, the ${S}_{21}$ -level of the edge-positional GD gradually was declined at all resonant modes. For a center-positional GD, the frequency not only was deviated into the high-frequency region, but its ${S}_{21}$ -level also gradually was declined for the second and fourth modes. Based on the experimental results, the resonant behavior indicated the edge-(center-) positional GD had the resolution (~0.01/gmL−1 or ~0.05 dB/gmL−1) at the second (second) and third (fourth) modes, respectively. Furthermore, we showed that the edge-positional GD sensing is more suitable when the resonator is associated with an active circuit system, and simultaneous sensing is also possible for different positions in multi-modes.

Correctly resolving textual mentions of people fundamentally entails making inferences about those people. Such inferences raise the risk of systematic biases in coreference resolution systems, including biases that can harm binary and non-binary trans and cis stakeholders. To better understand such biases, we foreground nuanced conceptualizations of gender from sociology and sociolinguistics, and investigate where in the machine learning pipeline such biases can enter a coreference resolution system. We inspect many existing data sets for trans-exclusionary biases, and develop two new data sets for interrogating bias in both crowd annotations and in existing coreference resolution systems. Through these studies, conducted on English text, we confirm that without acknowledging and building systems that recognize the complexity of gender, we will build systems that fail for: quality of service, stereotyping, and over- or under-representation, especially for binary and non-binary trans users.

Open-cell metamaterials prepared by additive manufacturing or replica techniques are typically prone to processing defects resulting from limited resolution, strut cross-section variations or internal strut porosity. These defects are expected to cause deviations from the ideal (CAD-based or template-based) target microstructures and thus from the envisaged properties. This paper investigates some of these effects in a quantitative manner. Based on computer-generated open Kelvin-cell (tetrakaidecahedral) alumina-based metamaterials, the effective thermal conductivity and elastic constants, mainly Young’s modulus, are calculated in dependence of the voxel size, strut thinning and strut wall thickness. It is shown that the porosity dependence of smooth, straight and full struts agrees closely to the Gibson-Ashby prediction for open-cell foams, while limited resolution and strut thinning leads to property values that tend to be lower and hollow struts lead to higher property values. The Pabst-Gregorova cross-property relation gives an excellent prediction of the conductivity-modulus correlation in all cases.

A novel non-contact optical thermometer, qualified with high sensitivity and temperature resolution, is urgently needed for temperature measuring of micro devices, moving objects and specific severe environments. Hence, a series of dual-emitting La5Si2BO13:Ce3+,Eu2+ phosphors were synthesized. The two ions show diverse responses with the changing in temperature. The variational emissions of Ce3+ and Eu2+ can be converted to FIR (fluorescence intensity ratio) signals. The maximal absolute sensitivity Sa and relative sensitivity Sr reach up to 0.07526%/K and 3.2241%/K, respectively. It is worthy noting that the Sa and Sr possess the same variation tendency and both have high values in the low temperature region (293–373 K), showing the great temperature measuring property especially in low temperature region. The temperature sensing characteristics are superior to the results of most previous reports. The energy transfer (ET) process is certified to occur from Ce3+ to Eu2+ ions. These studies indicate that La5Si2BO13: Ce3+,Eu2+ phosphor could have a good prospect for optical thermometry.

A Wireless Sensor Network (WSN) differs from conventional wireless or wired networks in that it interacts with the environment. Orthogonal Frequency Division Multiplexing (OFDM) was investigated as a possible interface technology for making effective use of bandwidth. Such networks have been proposed for a variety of purposes such as search and rescue, disaster assistance, and smart positioning systems. These applications often require a large number of wireless sensors that are powered by batteries and are designed for long-term, human-free deployment. Collisions between network nodes can significantly degrade performance in WSNs. Although increased bandwidth facilitates wireless access to high data frequencies, it is prohibitively expensive to increase due to spectrum limits. This necessitates making good use of the available bandwidth. OFDM has been considered as a possible interface mechanism for efficiently utilising bandwidth. While many signals available in WSN technology can be employed to mitigate collisions, multi-signal allocations may have a significant impact on the efficiency of multistage communications. Real-time multimedia flow raises the chance of sensor network failures and congestion, which reduces the efficiency of Quality of Service (QoS). The main goal of the Signal Allocation Scheme is to allocate an appropriate number of signals to any node in order to use professional bandwidth and assure QoS. Load balancing is intended to measure and prevent collisions caused by the number of available slots in the frame. Preparation is another important component in preventing collisions because it decreases delay and optimises energy utilisation. In this paper, an Integrated Signal Allocation Model with Effective Collision Resolution Model (ICAM-ECR) is used to deploy non-overlapping signals dynamically for varying application loads based on expected bandwidth estimation. The suggested model is compared to standard methods, and the findings reveal that the proposed model outperforms existing models.

Electrogenerated chemiluminescence microscopy (ECLM) provides a real-time imaging approach to visualize the surface-dependent catalytic activity of nanocatalysts, which helps to rationalize the design of catalysts. In this study, we first propose super-resolution ECLM that could measure the facet- and site-specific activities of a single nanoparticle with nanometer resolution. The stochastic nature of the ECL emission makes the generation of photons obey Poisson statistics, which fits the requirement of super-resolution radial fluctuation (SRRF). By processing an SRRF algorithm, the spatial resolution of ECL images achieved ca. 100 nm, providing more abundant details on electrocatalytic reactivities at the subparticle level. Beyond conventional wide-field ECL imaging, super-resolution ECLM provided the spatial distribution of catalytic activities at a Au nanorod and nanoplate with scales of a few hundred nanometers. It helped uncover the facet- and defect-dependent surface activity, as well as the dynamic fluctuation of reactivity patterns on single nanoparticles. The super-resolution ECLM provides high spatiotemporal resolution, which shows great potential in the field of catalysis, biological imaging, and single-entity analysis.

Multidimensional NMR spectroscopy provides a powerful tool for structure elucidation and dynamic analysis of complex samples, particularly for biological macromolecules. Multidimensional sparse sampling effectively accelerates NMR experiments while an efficient reconstruction method is generally required for unraveling spectra. Various reconstruction methods were proposed for pure Fourier NMR (only involving chemical shifts and J couplings detection). However, reconstruction concerned with Laplace-related NMR (i.e., involving relaxation or diffusion detection) is more challenging due to its ill-posed property. The existing Laplace-related NMR sparse sampling reconstruction methods suffer from poor resolution and possible artifacts in the resulting spectra owing to the pitfalls of the optimization algorithms. Herein, we propose a general approach for fast high-resolution reconstruction of multidimensional sparse sampling NMR, including pure Fourier, mixed Fourier-Laplace, and pure Laplace NMR, benefiting from the comprehensive sparse constraint and effective optimization algorithm and thus showing the promising prospects of multidimensional NMR.

Electrochemistry exploits local current heterogeneities at various scales ranging from the micrometer to the nanometer. The last decade has witnessed unprecedented progress in the development of a wide range of electroanalytical techniques allowing to reveal and quantify such heterogeneity through multiscale and multifonctionnal operando probing of electrochemical processes. However most of these advanced electrochemical imaging techniques, employing scanning probes, suffer from either low imaging throughput or limited imaging size. In parallel, optical microscopies, which can image a wide field of view in a single snapshot, have made considerable progress in terms of sensitivity, resolution and implementation of detection modes. Optical microscopies are then mature enough to propose, with basic bench equipment, to probe in a non destructive way a wide range of optical (and therefore structural) properties of a material in situ, in real time: under operating conditions. They offer promising alternative strategies for quantitative high-resolution imaging of electrochemistry. The first sections recall the optical properties of materials and how they can be probed optically. They discuss fluorescence, Raman, surface plasmon resonance, scattering or refractive index. Then the different optical microscopes used to image electrochemical processes are examined along with some strategies to extract quantitative electrochemical information from optical images. Finally the last section reviews some examples of in situ imaging, at micro- to nanometer resolution, and quantification of electrochemical processes ranging from solution diffusion to the conversion of molecular interfaces or solids., Comment: 66 pages, 23 figures. To be published in Encyclopedia of Electrochemistry

In this study, eight types of bacteria were cultivated, including Staphylococcus aureus. The infrared absorption spectra of the gas surrounding cultured bacteria were recorded at a resolution of 0.5 cm−1 over the wavenumber range of 7500–500 cm−1. From these spectra, we searched for the infrared wavenumbers at which characteristic absorptions of the gas surrounding Staphylococcus aureus could be measured. This paper reports two wavenumber regions, 6516–6506 cm−1 and 2166–2158 cm−1. A decision tree–based machine learning algorithm was used to search for these wavenumber regions. The peak intensity or the absorbance difference was calculated for each region, and the ratio between them was obtained. When these ratios were used as training data, decision trees were created to classify the gas surrounding Staphylococcus aureus and the gas surrounding other bacteria into different groups. These decision trees show the potential effectiveness of using absorbance measurement at two wavenumber regions in finding Staphylococcus aureus. Graphical abstract

Despite recent progress in our understanding of graft union formation, we still know little about the cellular events underlying the grafting process. This is partially due to the difficulty of reliably targeting the graft interface in electron microscopy to study its ultrastructure and three-dimensional architecture. To overcome this technological bottleneck, we developed a correlative light electron microscopy (CLEM) approach to study the graft interface with high ultrastructural resolution. Grafting hypocotyls of Arabidopsis thaliana lines expressing yellow FP or monomeric red FP in the endoplasmic reticulum (ER) allowed efficient targeting of the grafting interface for examination under light and electron microscopy. To explore the potential of our method to study sub-cellular events at the graft interface, we focused on the formation of secondary plasmodesmata (PD) between the grafted partners. We showed that four classes of PD were formed at the interface and that PD introgression into the cell wall was initiated equally by both partners. Moreover, the success of PD formation appeared not systematic with a third of PD not spanning the cell wall entirely. Characterizing the ultrastructural characteristics of these incomplete PD gives us insights into the process of secondary PD biogenesis. We found that the establishment of successful symplastic connections between the scion and rootstock occurred predominantly in the presence of thin cell walls and ER–plasma membrane tethering. The resolution reached in this work shows that our CLEM method advances the study of biological processes requiring the combination of light and electron microscopy.