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The article discusses the use of chatbot technology in the field of microscopy. The authors, Filip Braet and David Poger, highlight the potential benefits of chatbots in providing access to academic information and datasets. However, they also acknowledge the challenges and ethical considerations associated with using this technology in research. The authors share their experiences working with chatbots and express curiosity about the future role of AI in microscopy. They emphasize the importance of responsible and ethical use of AI in research and education. [Extracted from the article]

The abdominal wagging behavior of Polistes dominulus foundresses is highly conspicuous and frequently performed, but comprehensive descriptions are lacking. It has been suggested that abdominal wagging is involved in vibratory signaling, but the wagging behavior has not been distinguished from the substrate-borne signal, and nest vibrations have never been described. Here I provide a detailed description of the behavior and the first video-linked accelerometer recordings of nest vibrations. These recordings indicate that an impulsive vibration is produced when the adult female repeatedly strikes its abdomen against cell rims as it swings it across the nest surface. These strong vibrations propagate throughout the nest. Scanning electron microscopy reveals no specialized structures for vibration production on the abdomen or nest. These results provide a foundation for the mechanical playback studies required to experimentally determine the function of abdominal wagging. [ABSTRACT FROM AUTHOR]

Mixed matrix membranes (MMMs) have emerged as promising materials for various separation processes due to their tunable properties, enhanced separation performance and reproducibility. In this review paper, we provide a comprehensive overview of the methodologies, challenges, and applications associated with the characterization of MMMs using two advanced imaging techniques: Focused Ion Beam Scanning Electron Microscopy (FIB‐SEM) and Transmission Electron Microscopy (TEM). We begin by outlining the principles and capabilities of FIB‐SEM and TEM, emphasizing their suitability for studying the microstructure, morphology, and composition of MMMs at nanoscale resolution. Subsequently, we discuss the specific challenges and limitations encountered in the characterization of MMMs using these techniques, including sample preparation, image acquisition, and data interpretation. Furthermore, we review the diverse applications of FIB‐SEM and TEM in elucidating the structure‐property relationships of MMMs. Through illustrative examples, we highlight the valuable insights gained from these imaging techniques in optimizing MMMs for various separation applications. Finally, we propose future directions and emerging trends in MMM characterization, including the integration of lasers into FIB‐SEM and in situ characterization techniques, to address current challenges and push the boundaries of MMM design and performance. Overall, this review provides a comprehensive overview of the state‐of‐the‐art methodologies for characterizing MMMs using FIB‐SEM and TEM, identifies key challenges, and offers insights into future research directions aimed at harnessing the full potential of MMMs for sustainable separation technologies. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have garnered significant attention in recent years owing to their exceptional properties. Understanding the intricate relationship between the structure of a material and its properties is crucial for guiding the synthesis and application of these materials. (Scanning) Transmission electron microscopy (S)TEM imaging stands out as a powerful tool for structural characterization at the nanoscale, capable of detailing both periodic and aperiodic local structures. However, the high electron‐beam sensitivity of MOFs presents substantial challenges in their structural characterization using (S)TEM. This paper summarizes the latest advancements in low‐dose high‐resolution (S)TEM imaging technology and its application in MOF material characterization. It covers aspects such as framework structure, defects, and surface and interface analysis, along with the distribution of guest molecules within MOFs. This review also discusses emerging technologies like electron ptychography and outlines several prospective research directions in this field. [ABSTRACT FROM AUTHOR]

In this paper, we have modified the workflow of the traditional light transmission aggregometry (LTA) protocol to characterize tumor cell clusters in vitro in a quantifiable and multifaceted manner. Circulating tumor cell (CTC) clusters have high metastatic potential compared to single tumor cells traveling in the bloodstream. Thus, engineering new therapeutic strategies that specifically target this CTC population is essential. To accomplish this, quantifiable methods to characterize their therapeutic effect on tumor cell clusters is a prerequisite. The method presented here enables the user to precisely quantify the dissociation of cancer cell clusters in the presence of clinically relevant fibrinolytic agents, such as alteplase and tenecteplase. The efficacy of the fibrinolytic agents can be quantified using this in vitro assay, prior to conducting preclinical studies. Here, we have obtained the fibrinolytic activity data in terms of lag time to the initiation of tumor cell dissociation, time to 25% dissociation, and trend of dissociation over time. To validate the assay, cell counts and phase‐contrast microscopy images were recorded over time. Further, we explored an LTA‐assisted preparation of platelet–tumor‐cell clusters of calibrated size for potential downstream testing/applications. To assess whether the assay is applicable to characterize the dissociation of cancer cell clusters in the presence of platelets, we added low (50 000 platelets·μL−1), normal (200 000 platelets·μL−1) and high (450 000 platelets·μL−1) concentrations of platelets to the tumor cell clusters. In addition to dissociation parameters, microcopy images were recorded over time to validate the assay and enabled the enumeration of clusters and single cells. The correlative light electron microscopy (CLEM) technique was utilized to visualize the morphology and composition of platelet–tumor cell clusters. [ABSTRACT FROM AUTHOR]

The article is an introduction to the second volume of "Women in Microscopy," which features a collection of papers on various microscopy techniques and technologies. The volume includes contributions on topics such as surface passivation, time-modulated structured illumination, Mesolens imaging, array tomography, and quantification in life sciences microscopy. The article also highlights the implementation of an interdisciplinary bootcamp at UC Berkeley aimed at promoting networking and support for women in microscopy. The bootcamp provides opportunities for undergraduate students to connect with women role models in academia and industry. Other papers in the volume discuss improvements in glass coatings for microscopy, a temporal method for improving localisation precision, mesoscale standing wave imaging, and array tomography in 3D electron microscopy. The volume concludes with a review on microscopy data quantification in the life sciences. Overall, the article showcases the diverse contributions of women in the field of microscopy and highlights the importance of supporting and promoting gender equity in the discipline. [Extracted from the article]

While numerical aperture of transillumination at or above 1.25 can be achieved with a substage oiled Abbe condenser, such immersion-capable condensers can be expensive limiting their use in resource poor settings. Also the measurement of numerical aperture generated by illuminators has received relatively little attention in the literature compared to methods for measuring the numerical aperture of acceptance by objectives. In this article, I show how an inexpensive paper diffuser with refractive-index coupling to the sample slide can generate illumination of a numerical aperture of over 1.4 at a small fraction of the cost of oiled dioptric condensers of comparable numerical aperture. In addition, I present two ways in which a diffuser may also be used to measure the numerical aperture generated by an illuminator using either a calibrated index-coupled paper diffuser to implement an interpolative variation of the Horsfall method or a diffuser as a detector screen coupled to a self-built microscope slide-based illumination system apertometer. [ABSTRACT FROM AUTHOR]

Sample preparation is of utmost importance for any microscopy and microstructural analysis. Correct preparation will allow accurate interpretation of microstructural features. A well‐polished section is essential when scanning electron microscopy (SEM) is used in backscattering electron (BSE) mode and characteristic X‐rays are to be quantified using an energy‐dispersive spectroscopy (EDS) detector. However, obtaining a well‐polished section, especially for cementitious materials containing aggregates, is considered to be challenging and requires experience. A sample preparation procedure consists of cutting, grinding and polishing. Undercutting of soft and brittle paste between harder aggregates can be overcome by vacuum epoxy impregnation offering mechanical support in the matrix. Furthermore, most of the attention during the sample preparation is given to the polishing of the sample. There is a wide range of suggestions on polishing steps, ranging from grain sizes, time and applied force; however, the final assessment of a polish surface is often subjective and qualitative. Therefore, a quantitative, reproducible guidance on the grinding steps, effect of experimental parameters and the influence of different grinding steps on the surface quality are required. In this paper, the influence of grinding was quantitatively evaluated by a digital microscope equipped with optical profilometry tools, through a step‐wise procedure, including sample orientation, grinding time and the difference between cement paste and concrete. Throughout the grinding procedure, the surface profiles were determined after each grinding step. This showed the step‐wise change in surface roughness and quality during the grinding procedure. Finally, the surface qualities were evaluated using optical and electron microscopy, which show the importance of the grinding/prepolishing steps during sample preparation. [ABSTRACT FROM AUTHOR]

Combined with other materials and device improvements, Si anodes can provide a step change in Lithium‐ion battery properties, enabling cell energy density to exceed 400 Wh kg−1. Freestanding, large‐area anodes of 100% Si produced by a slurry‐free method without carbon or binders are introduced. Their structure, a dense network of interconnected high aspect ratio Si nanowires (Si NWs), is analogous to a nanotextile and provides handling like paper. In conventional liquid electrolytes, the anode capacity is 2500 mAh g−1 at high mass loadings (e.g., 6.6 mAh cm−2), and cycling stability is 76% after 200 deep cycles, and 100% after 1800 cycles when cycled at 1000 mAh g−1. The nanowire network structure reduces junction resistance between particles and prevents any pulverization upon cycling. Combined impedance and composition‐selective electron microscopy demonstrate that capacity fading is exclusively through the progressive increase of SEI thickness and resistance. Full cell capacity with NMC811 translates into an energy density of 420 Wh kg−1 at the true cell level. [ABSTRACT FROM AUTHOR]

Polymer composites of a segregated network structure are dielectric polymer granules coated with electrically conductive nanoparticles at a low content, the quantity of the junctions between the granules determines the composites' mechanical properties, and the percolation network formed by the nanoparticles determines the electrical conductivity. Here, the morphology and electron‐transport properties in reduced graphene oxide (rGO)‐filled composites with a segregated structure based on polyvinyl chloride (PVC), poly(vinylidene fluoride‐co‐tetrafluoroethylene) (P(VDF‐TFE)), and ultrahigh‐molecular‐weight polyethylene (UHMWPE) are studied. Optical and electron microscopies study of the microtome‐formed cross sections have shown the morphology to be dependent on the polymer—the thinnest rGO layers are in UHMWPE‐based composites, the thicker rGO layers are in PVC‐ and P(VDF‐TFE)‐based ones. The electrical conduction of the composites and the rGO‐paper occurs through the same hopping conduction mechanisms within the wide temperature range, which allows to use the composites in applications where pure rGO is considered. Owing to thicker rGO layers open to the environment, PVC‐ and P(VDF‐TFE)‐based composites are more attractive, rather than the UHMWPE ones, in applications where layered materials are needed, for example, in lithium‐ion batteries or supercapacitors. The UHMWPE‐based composites look more promising as electrically conductive materials when mechanical strength is important. [ABSTRACT FROM AUTHOR]

Inlays range among the most aesthetically pleasing and technically challenging glasses produced in the Ptolemaic period. Despite the central role of this phase in the history of glass technology, little is known about the recipes and the technological knowledge of the Egyptian artisans. This paper will thus focus on the study of the materials from the secondary workshop of Tebtynis (Fayum oasis, Egypt). We report the first multi‐methodological study comprising textural, chemical, and mineralogical analyses (optical microscopy, scanning electron microscopy coupled with energy‐dispersive system, electron probe microanalysis, and μ‐Raman spectroscopy) on a set of 81 colorless, white, blue, and green samples carefully selected among the 800+ glasses from the craft area now stored at the Museo Egizio, Turin (Italy). Our study offers the biggest compositional database of well‐dated Ptolemaic glasses currently available in the literature, highlighting some interesting novelties regarding the silica and alkali sources, and the coloring and opacifying techniques employed. The results suggest a specialized craft of traditional origin, but open to innovation and experimentation, as expected from transitional phases. [ABSTRACT FROM AUTHOR]

The article presents abstracts of papers presented at the 9th Annual Meeting of the Society for Cutaneous Ultrastructure Research, held at Leiden, the Netherlands, in April 1982. Fetal manifestation of bullous ichthyosiform erythroderma and prenatal diagnosis of the disease by means of electron microscopy of fetal skin biopsies was discussed. A female patient with a generalized congenital ichthyosis was presented. The clinical picture was characterized by a reticulate hyperkeratosis with a remarkable skin pattern. Immuno-electronmicroscopic study of Langerhans' cells was also presented.

An understanding of radiation damage effects suffered by biological samples during structural analysis using both X‐rays and electrons is pivotal to obtain reliable molecular models of imaged molecules. This special issue on radiation damage contains six papers reporting analyses of damage from a range of biophysical imaging techniques. For X‐ray diffraction, an in‐depth study of multi‐crystal small‐wedge data collection single‐wavelength anomalous dispersion phasing protocols is presented, concluding that an absorbed dose of 5 MGy per crystal was optimal to allow reliable phasing. For small‐angle X‐ray scattering, experiments are reported that evaluate the efficacy of three radical scavengers using a protein designed to give a clear signature of damage in the form of a large conformational change upon the breakage of a disulfide bond. The use of X‐rays to induce OH radicals from the radiolysis of water for X‐ray footprinting are covered in two papers. In the first, new developments and the data collection pipeline at the NSLS‐II high‐throughput dedicated synchrotron beamline are described, and, in the second, the X‐ray induced changes in three different proteins under aerobic and low‐oxygen conditions are investigated and correlated with the absorbed dose. Studies in XFEL science are represented by a report on simulations of ultrafast dynamics in protic ionic liquids, and, lastly, a broad coverage of possible methods for dose efficiency improvement in modalities using electrons is presented. These papers, as well as a brief synopsis of some other relevant literature published since the last Journal of Synchrotron Radiation Special Issue on Radiation Damage in 2019, are summarized below. [ABSTRACT FROM AUTHOR]

M-doped TiO2 and mixed oxides M xO y-TiO2 (M = V, Bi, W) were synthesized by the reactive mineralization of ash-free filter paper under anhydrous conditions. Mixtures of metal chlorides (TiCl4 with VOCl3, WCl6, or BiCl3) were reacted directly with cellulose, and three different Ti/M atomic ratios were used (99, 19, and 9). The resulting materials consist of original nanoflower assemblies of needle-shaped primary particles. Their physicochemical characteristics were investigated by various techniques (X-ray diffraction, diffuse-reflectance UV/Vis spectroscopy, electron microscopy, and elemental analysis). The incorporation of the doping metal or the formation of mixture of oxides with TiO2 (WO3, Bi2O3) depends on the metal and the proportions used. The photocatalytic activities of the materials were tested for the degradation of phenol. The vanadium-doped materials exhibit true solid-solution formation and their band gaps shift into the visible range. [ABSTRACT FROM AUTHOR]

Low‐energy electron microscopy (LEEM) taken as intensity–voltage (I–V) curves provides hyperspectral images of surfaces, which can be used to identify the surface type, but are difficult to analyse. Here, we demonstrate the use of an algorithm for factorizing the data into spectra and concentrations of characteristic components (FSC3) for identifying distinct physical surface phases. Importantly, FSC3 is an unsupervised and fast algorithm. As example data we use experiments on the growth of praseodymium oxide or ruthenium oxide on ruthenium single crystal substrates, both featuring a complex distribution of coexisting surface components, varying in both chemical composition and crystallographic structure. With the factorization result a sparse sampling method is demonstrated, reducing the measurement time by 1–2 orders of magnitude, relevant for dynamic surface studies. The FSC3 concentrations are providing the features for a support vector machine‐based supervised classification of the surface types. Here, specific surface regions which have been identified structurally, via their diffraction pattern, as well as chemically by complementary spectro‐microscopic techniques, are used as training sets. A reliable classification is demonstrated on both example LEEM I–V data sets. Lay description: Low‐energy electron microscopy (LEEM) is a powerful experimental method to image surfaces, thin films and nanoparticles. An incident beam of low energy electrons (<50eV) is reflected from the surface and used to create an image of the investigated sample. The structure of the first few atomic layers of the investigated sample is encoded in the energy dependent electron reflectivity of the surface, so called intensity versus electron energy, or in short LEEM I‐V, spectra, which however are difficult and time‐consuming to interpret. In this paper we present a factorization method to describe the LEEM I‐V hyperspectral data as a combination of characteristic components which are defined by their concentrations and spectra. Using the concentration maps, we demonstrate a supervised classification method which provides a fast and reliable classification of surface reconstructions, as shown on two examples, ruthenium oxide (RuO2), and praseodymium oxide (PrOx). For PrOx, the factorization and classification reveals that the surface consists of a flat substrate with bands of coalesced oxide islands which nucleated at the atomic step edges of the Ru(0001) substrate. The PrOx regions comprise a complex substructure of five distinguishable phases. For RuO2, the method reveals the different types of islands that exist in the rich RuO2/Ru system, where different RuO2 orientations characteristic of the Ru oxidation can be separated by their I‐V spectra. Furthermore, using the extracted component spectra and the classification of the concentrations, demonstrate a sparse sampling method to reduce the number of acquired spectral points required for classification. A reduction of the acquisition time by a factor of 30 per classification is achieved for the example data. [ABSTRACT FROM AUTHOR]

The article information on the review paper regarding correlated light & electron microscopy from the manufacturer DELMIC, published in the journal "Nature Methods."

Summary: In this paper, we explore the development of the Cryo‐Lift‐Out (cryo‐LO) technique as preparation tool for cryogenic transmission electron microscopy (cryo‐TEM). What started in early work defying what was considered 'practically impossible' has developed into state‐of‐the‐art practical reality. This paper presents the key hardware, basic principles and key considerations for the practical usage of cryogenic Lift‐Out for those new to the field. Detailed protocols and in‐depth description of considerations and points for further development are presented. The authors have attempted to formalise everything known about the technique gathered together from their expertise gained in the development of this approach. Lay Description: A major challenge in electron microscopy is the production of suitable samples from hydrated biological and soft‐matter materials for subnanometre resolution imaging in a cryo‐Transmission Electron Microscope (TEM). A well‐known solution for room temperature materials is called (in situ) Lift‐Out. It uses a fine needle that picks up a tiny section called a lamella. Lamellae are made by a Focused Ion Beam (FIB). In this paper, we seek to set out the beginnings of Lift‐Out sample preparation conducted under cryogenic conditions and the development of this approach as applied to frozen, hydrated biological and soft‐matter samples. We discuss the required basic hardware and provide a thorough description of developed protocols. We aim at those new to the field of cryo‐Lift‐Out to fully educate them in the finer points of hardware setup and practical considerations when attempting to perform cryo‐Lift‐Out and to demonstrate what has been achieved thus far. We also discuss areas of further improvement and talking points for the future direction of this promising sample preparation technique. [ABSTRACT FROM AUTHOR]

Cryogenic electron microscopy (cryoEM) has emerged as a revolutionary method for solving high‐resolution structures and studying the dynamics of macromolecular complexes and viruses in near‐native states. However, the availability of the equipment, and the time and cost needed for training, severely limit the opportunities for training. To solve these problems, a virtual reality‐based training system, CryoVR, has been developed to prepare trainees before operating real‐world cryoEM equipment. This paper describes the design and assessment of CryoVR (available at https://www.purdue.edu/cryoVR), which helps users learn cryoEM experimental procedures in a virtual environment, allowing immersive training with step‐by‐step tutorials with vivid visual, audio and text guidance. Implemented as a training step before a novice user interacts with the expensive real‐world cryoEM equipment, CryoVR can help users to become familiar with hands‐on operational procedures through multiple training modules and earning certificates after passing the built‐in Exam mode. Qualitative evaluation and feedback of CryoVR from users with various levels of cryoEM experience indicate the substantial value of CryoVR as a tool for a comprehensive cryoEM procedural training. [ABSTRACT FROM AUTHOR]

In this paper, we present a methodology for measuring the reaction degree of ground granulated blast furnace slag (GGBFS) in alkali‐activated cements using neural network based image analysis. The new methodology consists of an image analysis routine in which the segmentation of the back scattered electron (BSE) (SEM) images is based on a deep learning U‐net. This methodology was applied to and developed for NaOH‐activated slag cements and validated against independently measured XRD results. In a next step the developed method was applied to NaOH‐Na2SO4‐activated systems, to check the broader applicability. The neural networks based image analysis results were shown to correlate well with the XRD results. Once the model was trained, it segmented images fast and accurately. Furthermore, the model trained on the NaOH‐activated systems was readily applicable on NaOH‐Na2SO4‐activated system indicating that the model generalises well. As such, the developed methodology and models can be more performant and robust than conventional threshold‐based image segmentation. The method's accuracy, replicability and transferability make it a promising tool for material analysis and characterisation. [ABSTRACT FROM AUTHOR]

Summary: In Life Science research, electron microscopy (EM) is an essential tool for morphological analysis at the subcellular level as it allows for visualization at nanometer resolution. However, electron micrographs contain image degradations such as noise and blur caused by electromagnetic interference, electron counting errors, magnetic lens imperfections, electron diffraction, etc. These imperfections in raw image quality are inevitable and hamper subsequent image analysis and visualization. In an effort to mitigate these artefacts, many electron microscopy image restoration algorithms have been proposed in the last years. Most of these methods rely on generic assumptions on the image or degradations and are therefore outperformed by advanced methods that are based on more accurate models. Ideally, a method will accurately model the specific degradations that fit the physical acquisition settings. In this overview paper, we discuss different electron microscopy image degradation solutions and demonstrate that dedicated artefact regularisation results in higher quality restoration and is applicable through recently developed probabilistic methods. [ABSTRACT FROM AUTHOR]

Objectives: This paper aims to study the effect of the active form of vitamin D (calcitriol) on the internalized Porphyromonas gingivalis in macrophages and to assess the role of autophagy during this process. Materials and methods: Quantitative RT‐PCR and bacteria culture were used to quantify live P. gingivalis internalized into U937‐derived macrophages. Western blot assays were performed to detect the effect of P. gingivalis and calcitriol on autophagy in macrophages. Transmission electron microscope was used to observe the effect of calcitriol on the status of internalized P. gingivalis. Colocalization of P. gingivalis with the autophagosome and lysosome markers was observed by confocal laser scanning microscopy. Results: Calcitriol caused a dose‐dependent decrease in live P. gingivalis numbers and promoted both the endogenous and P. gingivalis‐induced autophagy in macrophages. Calcitriol significantly promoted the destruction of P. gingivalis and the colocalization of P. gingivalis with autophagosome and lysosome markers. Conversely, with 3‐MA, live P. gingivalis numbers in macrophages increased significantly and inhibition effect of calcitriol on the number of live P. gingivalis was attenuated. Conclusion: In U937‐derived macrophages, calcitriol may promote colocalization of P. gingivalis with autophagosomes and lysosomes, namely autophagy process, to degrade live P. gingivalis. [ABSTRACT FROM AUTHOR]

Maya blue is a pigment found in different archaeological sites of different cultures from Mesoamerica, and also in colonial buildings in Mexico and Cuba. The pigment is made from a thermally treated mixture of indigo and palygorskite. Pigment samples from Aztec and non‐Aztec archaeological sites as well as reference Yucatecan palygorskites were studied in this paper to assess their differences. The characterization of the samples was carried out by a combination of a crystal–chemical‐point analyses using electron microscopy to obtain the structural formulae of the palygorskite crystals, and studied using high‐resolution X‐ray diffraction. The data show evidence that the palygorskite used by non‐Aztec cultures, such as the Maya, is compatible with palygorskite from known sources in the Yucatan Peninsula, while the palygorskite used by the Aztec culture is different in its structure and has an origin that is still unknown. [ABSTRACT FROM AUTHOR]

A connectivity graph of neurons at the resolution of single synapses provides scientists with a tool for understanding the nervous system in health and disease. Recent advances in automatic image segmentation and synapse prediction in electron microscopy (EM) datasets of the brain have made reconstructions of neurons possible at the nanometer scale. However, automatic segmentation sometimes struggles to segment large neurons correctly, requiring human effort to proofread its output. General proofreading involves inspecting large volumes to correct segmentation errors at the pixel level, a visually intensive and time‐consuming process. This paper presents the design and implementation of an analytics framework that streamlines proofreading, focusing on connectivity‐related errors. We accomplish this with automated likely‐error detection and synapse clustering that drives the proofreading effort with highly interactive 3D visualizations. In particular, our strategy centers on proofreading the local circuit of a single cell to ensure a basic level of completeness. We demonstrate our framework's utility with a user study and report quantitative and subjective feedback from our users. Overall, users find the framework more efficient for proofreading, understanding evolving graphs, and sharing error correction strategies. [ABSTRACT FROM AUTHOR]

Cysteine (Cys) is an amino acid found in the body that exerts a good antioxidant effect. Sensitive detection of Cys has far‐reaching significance both in the cosmetics industry and biochemical reports. This paper showed that Fe‐MIL‐88NH2. Fe‐MIL‐88NH2 particles were prepared using solvothermal synthesis and their structure was determined using powder X‐ray diffraction, FT‐IR, electron microscopy, as well as N2 adsorption‐desorption measurements. Because of the large channels present in the frame, Fe‐MIL‐88NH2 quickly removed hazardous cationic dyes from water within several minutes. Luminescence tests showed Fe‐MIL‐88NH2 selected Cys featuring great sensitivity in the water, with a detection limit of 5.33 μM. A CCK8 experiment found that Fe‐MIL‐88NH2 had low cytotoxicity. Additionally, the constructed fluorescent platform was used as one signaling tool in monitoring Cys for detecting exo/endogenous Cys in A549 cells. [ABSTRACT FROM AUTHOR]

Spatial resolution is a fundamental parameter in structural sciences. In crystallography, the resolution is determined from the detection limit of high-angle diffraction in reciprocal space. In electron microscopy, correlation in the Fourier domain is used for estimating the resolution. In this paper, we report a method for estimating the spatial resolution of real images from a logarithmic intensity plot in the Fourier domain. The logarithmic intensity plots of test images indicated that the full width at half maximum of a Gaussian point spread function can be estimated from the images. The spatial resolution of imaging X-ray microtomography using Fresnel zone-plate optics was also estimated with this method. A cross section of a test object visualized with the imaging microtomography indicated that square-wave patterns up to 120-nm pitch were resolved. The logarithmic intensity plot was calculated from a tomographic cross section of brain tissue. The full width at half maximum of the point spread function estimated from the plot coincided with the resolution determined from the test object. These results indicated that the logarithmic intensity plot in the Fourier domain provides an alternative measure of the spatial resolution without explicitly defining a noise criterion. [ABSTRACT FROM AUTHOR]

Lithium plating on graphite anode is triggered by harsh conditions of fast charge and low temperature, which significantly accelerates SOH (state of health) degradation and may cause safety issues of lithium ion batteries (LIBs). This paper has reviewed recent research progress of lithium plating on graphite anode. Firstly, we summarize the forming mechanisms of Li plating with corresponding influence factors, the detecting methods and hazard of Li plating. Then, approaches to suppress Li plating are discussed, including anode surface modification, electrolyte composition optimization and development of optimal charge strategies. Finally, we conclude and propose the remaining challenges and prospects in terms of mechanism research, detecting approaches, and suppressing methods of Li plating. This review highlights the development of Li plating research and plays a guiding rule of further study on Li plating in LIBs. [ABSTRACT FROM AUTHOR]

Osmium tetroxide is a strong oxidizing agent used in electron microscopy. Eye exposure may cause severe burns, and after inhalation or ingestion damage to the respiratory or gastrointestinal tract occurs. Exposure to osmium and its compounds is extremely rare. We present a case of a 32‐year‐old female stained by 9 mL of 2% osmium tetroxide in acetone during an accident in the laboratory, with rare dermal and ocular findings. Due to lack of data in toxicological databases and the absence of antidote, the therapy was symptomatic. Osmium was detected in serum 19 hours later (0.22 μg/L) and in urine during the 15‐hour collection (three samples—7.05, 1.65 and 8.45 μg/L). In blood serum on admission, after 1 and 2 days after exposure, the levels of iron (28.2, 39.8 and 50.5 μmol/L; reference range 5.8‐34.5 μmol/L) and transferrin receptor/ferritine were elevated. To our knowledge, this is the first paper documenting a significant absorption from the skin and potentially from the eye conjunctiva, based on serum and urine analysis. The relationship between increased iron in blood and exposure has not been described yet, and the mechanism remains unknown. The patient is being followed up for the unknown long‐term effects. [ABSTRACT FROM AUTHOR]

Summary: This paper takes a fundamental view of the electron energy loss spectra of monolayer and few layer MoS2. The dielectric function of monolayer MoS2 is compared to the experimental spectra to give clear criteria for the nature of different signals. Kramers–Krönig analysis allows a direct extraction of the dielectric function from the experimental data. However this analysis is sensitive to slight changes in the normalisation step of the data pretreatment. Density functional theory provides simulations of the dielectric function for comparison and validation of experimental findings. Simulated and experimental spectra are compared to isolate the π and π + σ surface plasmon modes in monolayer MoS2. Single‐particle excitations obscure the plasmons in the monolayer spectrum and momentum resolved measurements give indication of indirect interband transitions that are excited due to the large convergence and collection angles used in the experiment. Lay Description: Two‐dimensional materials offer a path forward for smaller and more efficient devices. Their optical and electronic properties give way to beat the limits set in place by Moore's Law. Plasmon are the collective oscillations of electrons and can confine light to dimensions much smaller than its wavelength. In this work we explore the plasmonic properties of MoS2, a representational candidate from a family of 2D materials known as transition metal dichalcogenides. High resolution electron microscopy and spectroscopy provide insights in the plasmonic properties of MoS2 down to an atomic scale. Experimental results show the relationship between plasmons and interband transitions in the electron energy loss spectrum. Density functional theory provides a theoretical support for the experimental findings and provides commentary on the fundamental underlying physics. [ABSTRACT FROM AUTHOR]

Summary: This paper addresses the problem of creating a large quantity of high‐quality training segmentation masks from scanning electron microscopy (SEM) images. The images are acquired from concrete samples that exhibit progressive amounts of degradation resulting from alkali–silica reaction (ASR), a leading cause of deterioration, cracking and loss of capacity in much of the nation's infrastructure. The target damage classes in concrete SEM images are defined as paste damage, aggregate damage, air voids and no damage. We approached the SEM segmentation problem by applying convolutional neural network (CNN)‐based methods to predict the damage classes due to ASR for each image pixel. The challenges in using the CNN‐based methods lie in preparing large numbers of high‐quality training labelled images while having limited human resources. To address these challenges, we designed damage‐ and context‐assisted approaches to lower the requirements on human resources. We then evaluated the accuracy of CNN‐based segmentation methods using the datasets prepared with these two approaches. Lay Description: This work is about automated segmentation of Scanning Electron Microscopy (SEM) images taken from core and prism samples of concrete. The segmentation must detect several damage classes in each image in order to understand properties of concrete‐made structures over time. The segmentation problem is approached with an artificial network (AI) based model. The training data for the AI model are created using damage‐ and context‐assisted approaches to lower the requirements on human resources. The access to all training data and to a web‐based validation system for scoring segmented images is available at https://isg.nist.gov/deepzoomweb/data/concreteScoring. [ABSTRACT FROM AUTHOR]

Using transmission electron microscopy (TEM), this study investigated the characteristics of smear layers after preparation of dentin surfaces using different methods. In addition, this study analyzed, using scanning electron microscopy (SEM), the interactions of smear layers with the various acidic agents used subsequently to treat the dentin surface. Mid‐coronal dentin surfaces were prepared according to one of five instrumentation methods: fracture; grinding with carbide bur; grinding with regular‐grit diamond bur; grinding with superfine‐grit diamond bur; or grinding with 600‐grit silicon carbide (SiC) abrasive paper. Then, each prepared dentin surface was further divided into control (no further treatment) or treatment with one of the following agents: phosphoric acid solution (PAS); phosphoric acid gel (PAG); Clearfil SE Bond 2 Primer (SE2); or Scotchbond Universal Adhesive (SBU). Longitudinal ultra‐thin sections were made for TEM observations. Dentin discs, representing each surface preparation and treatment method described above, were created, and the morphology was examined by SEM. The TEM results revealed differences in thickness and denseness of the smear layer, according to the different methods of instrumentation used to prepare the dentin surface. The two forms of phosphoric acid completely removed the smear layer in all groups. Agglomerated silica particles were observed on the top of the collagen layer after etching with PAG. For all dentin surfaces, except for that prepared with SiC, SE2 demonstrated better etching efficacy on different smear layers, whereas SBU provided only superficial interaction. [ABSTRACT FROM AUTHOR]

Cryo‐electron microscopy (cryo‐EM) has rapidly expanded with the introduction of direct electron detectors, improved image‐processing software and automated image acquisition. Its recent adoption by industry, particularly in structure‐based drug design, creates new requirements in terms of reliability, reproducibility and throughput. In 2016, Thermo Fisher Scientific (then FEI) partnered with the Medical Research Council Laboratory of Molecular Biology, the University of Cambridge Nanoscience Centre and five pharmaceutical companies [Astex Pharmaceuticals, AstraZeneca, GSK, Sosei Heptares and Union Chimique Belge (UCB)] to form the Cambridge Pharmaceutical Cryo‐EM Consortium to share the risks of exploring cryo‐EM for early‐stage drug discovery. The Consortium expanded with a second Themo Scientific Krios Cryo‐EM at the University of Cambridge Department of Materials Science and Metallurgy. Several Consortium members have set up in‐house facilities, and a full service cryo‐EM facility with Krios and Glacios has been created with the Electron Bio‐Imaging Centre for Industry (eBIC for Industry) at Diamond Light Source (DLS), UK. This paper will cover the lessons learned during the setting up of these facilities, including two Consortium Krios microscopes and preparation laboratories, several Glacios microscopes at Consortium member sites, and a Krios and Glacios at eBIC for Industry, regarding site evaluation and selection for high‐resolution cryo‐EM microscopes, the installation process, scheduling, the operation and maintenance of the microscopes and preparation laboratories, and image processing. [ABSTRACT FROM AUTHOR]

Summary: Detecting crossovers in cryo‐electron microscopy images of protein fibrils is an important step towards determining the morphological composition of a sample. Currently, the crossover locations are picked by hand, which introduces errors and is a time‐consuming procedure. With the rise of deep learning in computer vision tasks, the automation of such problems has become more and more applicable. However, because of insufficient quality of raw data and missing labels, neural networks alone cannot be applied successfully to target the given problem. Thus, we propose an approach combining conventional computer vision techniques and deep learning to automatically detect fibril crossovers in two‐dimensional cryo‐electron microscopy image data and apply it to murine amyloid protein A fibrils, where we first use direct image processing methods to simplify the image data such that a convolutional neural network can be applied to the remaining segmentation problem. Lay Description: The ability of protein to form fibrillary structures underlies important cellular functions but can also give rise to disease, such as in a group of disorders, termed amyloid diseases. These diseases are characterised by the formation of abnormal protein filaments, so‐called amyloid fibrils, that deposit inside the tissue. Many amyloid fibrils are helically twisted, which leads to periodic variations in the apparent width of the fibril, when observing amyloid fibrils using microscopy techniques like cryogenic electron microscopy (cryo‐EM). Due to the two‐dimensional projection, parts of the fibril orthogonal to the projection plane appear narrower than parts parallel to the plane. The parts of small width are called crossovers. The distance between two adjacent crossovers is an important characteristic for the analysis of amyloid fibrils, because it is informative about the fibril morphology and because it can be determined from raw data by eye. A given protein can typically form different fibril morphologies. The morphology can vary depending on the chemical and physical conditions of fibril formation, but even when fibrils are formed under identical solution conditions, different morphologies may be present in a sample. As the crossovers allow to define fibril morphologies in a heterogeneous sample, detecting crossovers is an important first step in the sample analysis. In the present paper, we introduce a method for the automated detection of fibril crossovers in cryo‐EM image data. The data consists of greyscale images, each showing an unknown number of potentially overlapping fibrils. In a first step, techniques from image analysis and pattern detection are employed to detect single fibrils in the raw data. Then, a convolutional neural network is used to find the locations of crossovers on each single fibril. As these predictions may contain errors, further postprocessing steps assess the quality and may slightly alter or reject the predicted crossovers. [ABSTRACT FROM AUTHOR]

Although microscopes and image‐analysis software for electron cryomicroscopy (cryo‐EM) have improved dramatically in recent years, specimen‐preparation methods have lagged behind. Most strategies still rely on blotting microscope grids with paper to produce a thin film of solution suitable for vitrification. This approach loses more than 99.9% of the applied sample and requires several seconds, leading to problematic air–water interface interactions for macromolecules in the resulting thin film of solution and complicating time‐resolved studies. Recently developed self‐wicking EM grids allow the use of small volumes of sample, with nanowires on the grid bars removing excess solution to produce a thin film within tens of milliseconds from sample application to freezing. Here, a simple cryo‐EM specimen‐preparation device that uses components from an ultrasonic humidifier to transfer protein solution onto a self‐wicking EM grid is presented. The device is controlled by a Raspberry Pi single‐board computer and all components are either widely available or can be manufactured by online services, allowing the device to be constructed in laboratories that specialize in cryo‐EM rather than instrument design. The simple open‐source design permits the straightforward customization of the instrument for specialized experiments. [ABSTRACT FROM AUTHOR]

Summary: Background: Naturally occurring variants with deletions or mutations in the C‐terminal PreS1 domain from hepatitis B virus (HBV) chronically infected patients have been shown to promote HBsAg retention, inhibit HBsAg secretion and change the extracellular appearance of PreS1‐containing HBV particles (filaments and virions). Aims: To study the impact of N‐terminal deletion in preS1 domain on viral secretion and morphogenesis. Methods: An HBV mutant with 15 amino acids (aa 25‐39) deletion in N‐terminal preS1 was isolated. Intracellular and extracellular HBsAg were quantified by Western blot. Subcellular HBsAg distribution was analysed by confocal laser scanning microscopy. The viral morphology was characterised by sucrose density gradient ultracentrifugation, Western blot, electron microscopy, HBV mixed ELISA and HBV particle gel essay. Results: Expression of this mutant genome released higher amounts of HBsAg in the form of shorter filaments. A significant fraction of semi‐enveloped virions was observed in the supernatant that has been unprecedented so far. Stepwise insertion of aa 25‐31, aa 32‐39 and aa 25‐39 increased the length of filaments. The rescue of aa 25‐31 and aa 25‐39 drastically reduced the amounts of extracellular HBsAg and semi‐enveloped virions, while such effects could not be observed after insertion of aa 32‐39, arguing against a simple spacer function of this region. The deletion and rescued mutants do not differ in subcellular HBsAg distribution and colocalisation with ER, Golgi and multivesicular bodies markers arguing against differences in release pathways. Conclusion: N‐terminal PreS1‐domain (aa 25‐31) determines HBsAg secretion and triggers proper assembly of PreS1‐containing particles. LINKED CONTENT This article is linked to Pasetto et al and Jiang et al papers. To view these articles, visit https://doi.org/10.1111/apt.15428 and https://doi.org/10.1111/apt.15452. [ABSTRACT FROM AUTHOR]

This paper describes the main results from an investigation into the strength and low‐cycle fatigue (LCF) behavior of a rolled plate of WE43 Mg alloy in its T5 condition at room temperature. The alloy was found to exhibit small tension/compression yield asymmetry and small anisotropy being stronger in transverse direction (TD) than in rolling direction (RD) along with some anisotropy in strain hardening. The LCF tests were conducted under strain‐controlled conditions with the strain amplitudes ranging from 0.6% to 1.4% without the mean strain component. While the stress amplitudes during the LCF were higher for tests along TD than RD, the LCF life was similar for both directions. As revealed by electron microscopy, the fractured surfaces under tension consisted mainly of microvoid coalescence with some transgranular facets, while those fractured in LCF showed a combination of intergranular fracture and transgranular facets with minor content of microvoid coalescence. [ABSTRACT FROM AUTHOR]

Single‐particle analysis by electron microscopy is a well established technique for analyzing the three‐dimensional structures of biological macromolecules. Besides its ability to produce high‐resolution structures, it also provides insights into the dynamic behavior of the structures by elucidating their conformational variability. Here, the different image‐processing methods currently available to study continuous conformational changes are reviewed. In this paper, the existing image‐processing approaches in electron microscopy for the analysis of continuous conformational changes of biological macromolecules are reviewed. [ABSTRACT FROM AUTHOR]

In this paper, the influence of heating up to 400°C on properties of the self‐compacting concrete containing recycled copper slag fine aggregate was investigated. The residual mechanical properties such as compressive strength, splitting tensile strength, elastic modulus, and stress–strain curve of the heated concrete were measured with the change in the porosity of concrete. Moreover, the resistance against the penetration of chloride ions (Cl−) into the concrete after the heating was also evaluated. For observing the micro‐structure around the fine aggregate in the concrete, scanning electron microscopy was employed. The experimental results showed that the compressive strength of the concrete decreased with the mixing of copper slag fine aggregate, although the residual compressive strength increased after heating up to 300°C with the rise in temperature. Mixing copper slag fine aggregate into concrete also reduced the residual elastic modulus and accelerated Cl− penetration into the self‐compacting concrete when the maximum temperature exceeded 200°C. [ABSTRACT FROM AUTHOR]

Catalytic fast pyrolysis of pretreated lignin (with hydrogen chloride solution) over FAU (15) zeolite uniquely yielded a high fraction of phenols, phenol alkoxys, and aromatic hydrocarbons. However, the zeolite underwent rapid deactivation. This paper reports the visualization of the structural changes during deactivation and regeneration of the zeolite is reported. The deactivated and regenerated zeolites were characterized by means of N2 physisorption, electron microscopy, X‐ray diffraction, magic angle spinning (MAS), and multiple quantum (MQ) nuclear magnetic resonance (NMR) techniques. The results indicated that, during catalyst deactivation, there was excessive coke deposition in the zeolite pore structure resulted in both pore blockage and active site poisoning. The coke was removed by calcination of the spent catalyst in air at high temperature >550 °C which resulted in restoring the porosity and the activity to a large extent. However, the recovery of catalytic activity was incomplete attributing to irreversible structural changes in the catalyst during the deactivation and regeneration process. By fine‐tuning the reaction conditions and the regeneration of the catalyst, the catalyst performance after reactivation was optimized. Catalyst regeneration after mild coke deposition (that is, after a few catalytic cycles) and mild oxidation conditions (low temperature and slow‐heating ramp) are beneficial. Irreversible! The zeolite for catalytic fast pyrolysis of pretreated lignin deactivated quickly and the recovery of catalytic activity was incomplete attributing to irreversible structural changes during the deactivation and regeneration process. By fine‐tuning the reaction conditions and the regeneration of the catalyst, the catalyst performance after reactivation was optimized. [ABSTRACT FROM AUTHOR]

This paper is dedicated to a systematic study on the selected type of core‐shell magnetic nanoparticles. Described fabrication procedure adopts the idea of seeds‐based synthesis followed by subsequent layer growth. Each layer of formed particles is obtained from complexes of M(acac)x, where M stands for 3d elements (Fe, Co, Ni, Mn) and x is equal to 2 or 3 resulting in oxide formation. Obtained core‐shell nanoparticles are structurally examined by X‐ray diffraction, infra‐red spectroscopy, and transmission electron microscopy. Magnetic properties of the proposed nanoparticles are tested by Mössbauer spectroscopy. Variable in layered manner composition allows for tuning of physicochemical properties of the investigated material. Designed on demand layer‐by‐layer growth gives the opportunity to obtain desired final properties of, for example, sensing character or selectivity of interacting spices. [ABSTRACT FROM AUTHOR]

Abstract: Electron microscopy of leaf samples displaying streak symptoms from enset (Ensete ventricosum), a banana‐like plant widely cultivated in Ethiopia, showed the presence of bacilliform shaped virions as known for badnaviruses. DNA extracts subjected to rolling circle amplification (RCA), polymerase chain reaction (PCR) and cloning and sequence analysis revealed that the virus has a circular double‐stranded DNA genome of 7,163 nucleotides encoding predicted proteins of 21.5 kDa, 14.5 kDa and 202.5 kDa, a genome organization known for badnaviruses. The virus is phylogenetically most closely related to Sugarcane bacilliform Guadeloupe D virus with a nucleotide sequence identity of 77.2% at the conserved RT/RNase‐H region and 73.6% for the whole genome. Following the current species demarcation criteria, the virus should be considered as an isolate of a new species in the genus Badnavirus for which the name Enset leaf streak virus (ELSV) is suggested. Leaf samples from enset and banana were screened using virus‐specific primers, and ELSV was detected in six of 40 enset but not found in any of 61 banana samples. On the other hand, Banana streak OL virus (BSOLV) was detected from the majority (60%) of symptomatic banana samples but not from enset samples. This paper reports the first full‐genome sequence of a putative new badnavirus species infecting plants in the genus Ensete. In addition, this is the first report of the occurrence of BSOLV in Ethiopia. [ABSTRACT FROM AUTHOR]

Abstract: Nickel is a crucial catalyst for its excellent performance in active carbon atom–related catalysis such as hydrocarbon steam reforming and 1D carbon nanostructures preparation. The carbon diffusion activity in Ni is of critical importance in understanding the catalytic behavior and thereby the performance optimization. However, the carbonization process is still vague because of the hardly identified intermediates. In this paper, the metastable intermediates of nickel carbonization process are successfully stabilized by taking advantage of the epitaxial growth to elevate the structure transformation energy barrier. X‐ray diffraction, high‐resolution transmission electron microscopy, and synchrotron X‐ray absorption near edge structure data evidence the face‐centered cubic (fcc)Ni x C nature of the intermediates and thus an fccNi x C‐intermediated nickel carbonization process from fccNi to hexagonal close‐packed (hcp)‐Ni3C is revealed, which is also confirmed by the Vienna ab initio simulation package calculation from the viewpoint of energy evolution. To the best of the knowledge, it is the first time to report the identification of the fccNi x C. More importantly, the introduction of Au is found promoted the catalytic growth of graphitic carbon using either oleylamine or C2H4 as carbon resource. The Au@Ni‐based hybrid catalysts exhibit lower reaction temperature and much higher carbon output than pure Ni. [ABSTRACT FROM AUTHOR]

Summary: Serial block face scanning electron microscopy (SBF‐SEM) is a relatively new technique that allows the acquisition of serially sectioned, imaged and digitally aligned ultrastructural data. There is a wealth of information that can be obtained from the resulting image stacks but this presents a new challenge for researchers – how to computationally analyse and make best use of the large datasets produced. One approach is to reconstruct structures and features of interest in 3D. However, the software programmes can appear overwhelming, time‐consuming and not intuitive for those new to image analysis. There are a limited number of published articles that provide sufficient detail on how to do this type of reconstruction. Therefore, the aim of this paper is to provide a detailed step‐by‐step protocol, accompanied by tutorial videos, for several types of analysis programmes that can be used on raw SBF‐SEM data, although there are more options available than can be covered here. To showcase the programmes, datasets of skeletal muscle from foetal and adult guinea pigs are initially used with procedures subsequently applied to guinea pig cardiac tissue and locust brain. The tissue is processed using the heavy metal protocol developed specifically for SBF‐SEM. Trimmed resin blocks are placed into a Zeiss Sigma SEM incorporating the Gatan 3View and the resulting image stacks are analysed in three different programmes, Fiji, Amira and MIB, using a range of tools available for segmentation. The results from the image analysis comparison show that the analysis tools are often more suited to a particular type of structure. For example, larger structures, such as nuclei and cells, can be segmented using interpolation, which speeds up analysis; single contrast structures, such as the nucleolus, can be segmented using the contrast‐based thresholding tools. Knowing the nature of the tissue and its specific structures (complexity, contrast, if there are distinct membranes, size) will help to determine the best method for reconstruction and thus maximize informative output from valuable tissue. [ABSTRACT FROM AUTHOR]

This paper highlights the contribution of transmission electron microscopy (TEM) when combined with scanning electron microscopy and energy‐dispersive X‐ray microanalysis (SEM/XEDS) to characterize objects in archaeology. The application of TEM in archaeology is not yet a common tool, but it may provide data that are significant to understanding pre‐Columbian gold metallurgy, specifically the gilding and silvering methods. Two gilded rods were studied using a combination of TEM and SEM/XEDS techniques. The objects were found at the Atacames archaeological site, in the Esmeraldas region, Ecuador, which was occupied between ad 750 and 1526 by the Atacames culture. The microchemical and structural results of the inner and the external gilded part of the artefacts support the hypothesis of a gold diffusion to the surface enhanced by chemical treatment with chloride‐rich solutions, heating and successive annealing processes. The present study reveals that microstructural investigation by TEM provides useful information with which to investigate the techniques used to modify the chemical surface composition of pre‐Columbian artefacts. [ABSTRACT FROM AUTHOR]

Visualization of scientific data is crucial not only for scientific discovery but also to communicate science and medicine to both experts and a general audience. Until recently, we have been limited to visualizing the three‐dimensional (3D) world of biology in 2 dimensions. Renderings of 3D cells are still traditionally displayed using two‐dimensional (2D) media, such as on a computer screen or paper. However, the advent of consumer grade virtual reality (VR) headsets such as Oculus Rift and HTC Vive means it is now possible to visualize and interact with scientific data in a 3D virtual world. In addition, new microscopic methods provide an unprecedented opportunity to obtain new 3D data sets. In this perspective article, we highlight how we have used cutting edge imaging techniques to build a 3D virtual model of a cell from serial block‐face scanning electron microscope (SBEM) imaging data. This model allows scientists, students and members of the public to explore and interact with a “real” cell. Early testing of this immersive environment indicates a significant improvement in students’ understanding of cellular processes and points to a new future of learning and public engagement. In addition, we speculate that VR can become a new tool for researchers studying cellular architecture and processes by populating VR models with molecular data. [ABSTRACT FROM AUTHOR]

This paper presents a novel fast Fourier transform (FFT)-based exhaustive search method extended to off-grid translational and rotational degrees of freedom. The method combines the advantages of the FFT-based exhaustive search, which samples all the conformations of a system under study on a grid, with a local optimization technique that guarantees to find the nearest optimal off-grid conformation. The method is demonstrated on a fitting problem and can be readily applied to a docking problem. The algorithm first samples a scoring function on a six-dimensional grid of size N6 using the FFT. This operation has an asymptotic complexity of O( N6log N). Then, the method performs the off-grid search using a local quadratic approximation of the cost function and the trust-region optimization algorithm. The computation of the quadratic approximation is also accelerated by FFT at the same additional asymptotic cost of O( N6log N). The method is demonstrated by fitting atomic protein models into several simulated and experimental maps from cryo-electron microscopy. The method is available at . [ABSTRACT FROM AUTHOR]

Plasma treatments are established methods to functionalise carbon nanotubes (CNTs) and modify their surface structure. This paper presents a mild glow-discharge plasma treatment of aligned arrays of multi-walled carbon nanotubes employing sulfur hexafluoride (SF6), ammonia (NH3), and their mixtures as process gases. For the latter, sulfur was detected at the tip and sidewalls of the nanotubes via energy-dispersive X-ray spectroscopy, while electron microscopy served as method to verify the structural integrity of the CNTs after the plasma treatment. This approach provides the basis for an easy and quick alternative to existing sulfur functionalisation methods of MWCNTs. Furthermore, the proposed method can conveniently be applied to carbon nanotube arrays on substrate while preserving their structure and alignment. [ABSTRACT FROM AUTHOR]

This paper focuses on the characterization of materials from fragmented pieces of an imperial lacquer plate in the Luozhuang Han tomb, which dates to the early Western Han dynasty. Various non-invasive and minimally invasive techniques were performed, including optical and electron microscopy, XRF, Raman spectromicroscopy, FT-IR, XRD and THM-Py-GC/MS. The lacquerware pieces consist of a five-layer structure, which includes (from the top): a red pigmented layer, two lacquer finish layers, a ground layer and a canvas/wood foundation layer. The red layer consists of ground cinnabar mixed with urushi. The lacquer finish layers are made of urushi mixed with perilla or tallow tree oil, without any pigment. The ground layer is a mixture of organic materials including urushi, tree oil and amorphous carbon (possibly burned ashes) and inorganic fillers such as quartz, albite and potassium feldspar. Urushi was also identified in the canvas/wood foundation layer. Though highly degraded, the canvas is probably made of hemp (bast fibres). The identification of high concentration of drying oil indicates an intentional addition of oil into the urushi to retard the rate of hardening and to increase gloss. [ABSTRACT FROM AUTHOR]

In this paper, we describe three strata at the distal part of the pyroclastic-flow from the Tianchi volcano in 1215 (±15) eruption. One of the strata with crosslayers that are different from typical pyroclastic-flow strata may come from a ground-surge. The grain-size and scanning electron microscopy (SEM) analysis was performed to study the origin of the pyroclastic-flow. Characteristics of grain-size distribution show that it is similar with the ash cloud. Through the SEM analyses, we found some quench structures with less damage on the surfaces of the vitric pumices. These phenomena indicate that there has been hydration in the transportation processes at the distal of pyroclastic-flow. It has partly changed the transportation mechanism of pyroclastic-flow, which transitions form dense flow to diluted flow. This paper develops a new distal pyroclastic-flow model in the Tianchi volcano that can be divided into three stages, i.e. the quench stage, expanding stage and depositing stage. [ABSTRACT FROM AUTHOR]

This paper reports on the effect of the temperature used to activate kaolinite-based paper industry waste on the hydration products obtained when the activated waste was mixed with a lime solution. After activation at temperatures ranging from 500° to 700°C, clay waste exhibited high pozzolanic activity. Analysis with instrumental techniques such as X-ray diffraction, differential thermal analysis, infrared spectroscopy, and scanning electron microscopy showed that higher temperatures favored the formation of calcium aluminate hydrates, hydrotalcite- like compounds, and strätlingite, while at lower temperatures, CSH gels constituted the majority hydrated phase. According to these findings, reaction kinetics differed substantially from the results obtained at temperatures of 700°-800°C, particularly in terms of phase quantity and timing of appearance. This study shows that metakaolinite can be obtained from clay waste at temperatures of under 700°C. The hydrated phases forming under these conditions are the same as more observed at higher activation temperatures (>700°C). The main differences found were the sequence of phase formation and the quantity of hydrates detected. [ABSTRACT FROM AUTHOR]