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This paper considers the problem of reliable determination of the volume of cellulose fiber and its active surface to estimate or predict the properties of the paper or cardboard manufactured on its basis. To that end, we construct a 3D model of paper or cardboard fiber using contemporary methods of sample preparation for electron microscopy along with a professional powerful graphical editor. The 3D modeling included preparation of a series of microstructure paper slices with a step of at least 10 μm followed by their transformation into a 3D body. In the Object Properties section, the vector format graphic software sets the volume of fiber material, its surface and weight. Provided that the 3D body is correctly scaled, i.e., in accordance with the dimensions specified in microscopic images, the Object Properties section generates the required parameters. The obtained 3D fiber model also enables the force direction of interfiber interaction to be determined in the 3D coordinate system. Until now, the absence of a 3D fiber model in real dimensions has impeded evaluation of the actual value of interfiber bonding forces. These forces, as vector quantities, are characterized by not only numerical values, but also directionality. [ABSTRACT FROM AUTHOR]

[Display omitted] • Seminal papers in Toxoplasma research are revisited. • We focus on a paper that contributed to uncovering the complete life-cycle of Toxoplasma. • A paper that revealed some of the unique cellular biology of the parasite is examined. • A study that elucidated the nature of the compartment in which Toxoplasma resides is described. • We revisit a seminal paper in understanding the immune responses to Toxoplasma infection. Since Nicolle, Manceaux and Splendore first described Toxoplasma gondii as a parasite of rodents and rabbits in the early 20th century, a diverse and vigorous research community has been built around studying this fascinating intracellular parasite. In addition to its importance as a pathogen of humans, livestock and wildlife, modern researchers are attracted to T. gondii as a facile experimental system to study many aspects of evolutionary biology, cellular biology, host-microbe interactions, and host immunity. For new researchers entering the field, the extensive literature describing the biology of the parasite, and the interactions with its host, can be daunting. In this review, we examine four foundational studies that describe various aspects of T. gondii biology, presenting a 'journal club'-style analysis of each. We have chosen a paper that established the beguiling life cycle of the parasite (Hutchison et al., 1971), a paper that described key features of its cellular biology that the parasite shares with related organisms (Gustafson et al., 1954), a paper that characterised the origin of the unique compartment in which the parasite resides within host cells (Jones and Hirsch, 1972), and a paper that established a key mechanism in the host immune response to parasite infection (Pfefferkorn, 1984). These interesting and far-reaching studies set the stage for subsequent research into numerous facets of parasite biology. As well as providing new researchers with an entry point into the literature surrounding the parasite, revisiting these studies can remind us of the roots of our discipline, how far we have come, and the new directions in which we might head. [ABSTRACT FROM AUTHOR]

The cost of specialized scientific equipment can be high and with limited funding resources, researchers and students are often unable to access or purchase the ideal equipment for their projects. In the fields of materials science and mechanical engineering, fundamental equipment such as tensile testing devices can cost tens to hundreds of thousands of dollars. While a research lab often has access to a large-scale testing machine suitable for conventional samples, loading devices for meso- and micro-scale samples for in-situ testing with the myriad of microscopy tools are often hard to source and cost prohibitive. Open-source software has allowed for great strides in the reduction of costs associated with software development and open-source hardware and additive manufacturing have the potential to similarly reduce the costs of scientific equipment and increase the accessibility of scientific research. To investigate the feasibility of open-source hardware, a micro-tensile tester was designed with a freely accessible computer-aided design package and manufactured with a desktop 3D-printer and off-the-shelf components. To our knowledge this is one of the first demonstrations of a tensile tester with additively manufactured components for scientific research. The capabilities of the tensile tester were demonstrated by investigating the mechanical properties of Graphene Oxide (GO) paper and thin films. A 3D printed tensile tester was successfully used in conjunction with an atomic force microscope to provide one of the first quantitative measurements of GO thin film buckling under compression. The tensile tester was also used in conjunction with an atomic force microscope to observe the change in surface topology of a GO paper in response to increasing tensile strain. No significant change in surface topology was observed in contrast to prior hypotheses from the literature. Based on this result obtained with the new open source tensile stage we propose an alternative hypothesis we term ‘superlamellae consolidation’ to explain the initial deformation of GO paper. The additively manufactured tensile tester tested represents cost savings of >99% compared to commercial solutions in its class and offers simple customization. However, continued development is needed for the tensile tester presented here to approach the technical specifications achievable with commercial solutions. [ABSTRACT FROM AUTHOR]

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]

One hundred years ago, Robert Feulgen published a landmark paper in which he described the first method to stain DNA in cells and tissues. Although a century has passed since the discovery by Feulgen and Rossenbeck, the chemical reaction still exerts an important influence in current histochemical studies. Its contribution in diverse fields, spanning from biomedicine to plant biology, has paved the way for the most significant studies that constitute our current knowledge. The possibility to specifically explore the DNA in cell nuclei while quantifying its content makes it a contemporary and timeless method. Indeed, many histocytochemical studies following the 1924 paper have led to a deep understanding of genome organization in general as well as several specific mechanisms (e.g. DNA duplication or tumour pathology) that, nowadays, constitute some of the most fundamental pillars in biological investigations. In this review, we discuss the chemistry and application of the Feulgen reaction to both light and electron microscopy. [ABSTRACT FROM AUTHOR]

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]

Lead-free piezoelectric (K, Na)NbO3 (KNN) is considered one of the promising candidates for the replacement of Pb(ZrxTi1−x)O3. Several studies underlined the issue of K and Na volatility with increasing deposition temperatures, leading to high leakage currents in thin films, which still represents a major drawback for applications. This paper shows how epitaxial growth with concomitant preferred orientation of KNN films on niobium-doped strontium titanate (Nb:STO) depends on growth temperature and substrate strain. A preferred out-of-plane polar (001) orientation of KNN is obtained at high temperatures (>600 °C), while (100) orientation is dominant for lower ones. The (001) orientation is forced out-of-plane due to the sizeable in-plane stress derived from a negative lattice mismatch of pseudo-cubic KNN with respect to the underlying cubic (001) Nb:STO substrate. Moreover, we show that K-Na deficiency and high leakage of epitaxial KNN films deposited at high temperatures are accompanied by the appearance of a pattern of orthogonal spontaneous ferroelectric domains aligned to the [100] and [010] directions of Nb:STO. This pattern, visible in secondary electron microscopy, piezoforce response microscopy, and conductive atomic force microscopy images, is uncorrelated to the surface morphology. Supported by reciprocal space mapping by x-ray diffraction, this phenomenon is interpreted as the result of strain relaxation via ferroelectric domain formation related to K-Na deficient films displaying a sizable and increasing compressive strain when grown on Nb:SrTiO3. Our findings suggest that strain engineering strategies in thin films could be used to stabilize specific configurations of piezo- and ferroelectric domains. [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]

This paper presents a root cause analysis case study of defective Hall effect sensor devices. The study identified a complex failure mode caused by chip–package interaction, which has a similar signature to discharging defects such as ESDFOS (electrostatic discharge from outside to surface). However, the study revealed that the defect was induced by local mechanical force applied to IC structures due to the presence of large irregular shaped filler particles within the mold compound. Extensive failure analysis work was conducted to identify the failure mode, including the development of a new backside analysis strategy to preserve the mold compound during IC defect localization and screening. A combination of different failure analysis techniques was used, including CMP delayering, PFIB trenching, SEM PVC imaging and large area FIB cross-sectioning. The study found that the mold compound of the package caused thermo-mechanical strain onto the silica filler particle due to epoxy shrinkage during the molding process. Additionally, extra-large, irregularly shaped filler particles (called twin particles), located on top of the chip surface, can cause locally high compression stresses onto the IC layers, initiating cracks in the isolation layers under certain conditions forming a leakage path over the time. Thermo-mechanical finite element analysis was applied to verify the mechanical load condition for these large irregular shaped filler particles. As a result, an additional polyimide layer was introduced onto the IC to mitigate the mechanical stress of mold compound particles to avoid this failure mode. [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]

The plate-like graphene shells (GS) produced by an original methane pyrolysis method and their derivatives graphene oxide (GO) and graphene oxide paper (GO-P) were evaluated with luminescent Escherichia coli biotests and additional bacterial-based assays which together revealed the graphene-family nanomaterials’ toxicity and bioactivity mechanisms. Bioluminescence inhibition assay, fluorescent two-component staining to evaluate cell membrane permeability, and atomic force microscopy data showed GO expressed bioactivity in aqueous suspension, whereas GS suspensions and the GO-P surface were assessed as nontoxic materials. The mechanism of toxicity of GO was shown not to be associated with oxidative stress in the targeted soxS::lux and katG::lux reporter cells; also, GO did not lead to significant mechanical disruption of treated bacteria with the release of intracellular DNA contents into the environment. The well-coordinated time- and dose-dependent surface charge neutralization and transport and energetic disorders in the Escherichia coli cells suggest direct membrane interaction, internalization, and perturbation (i.e., “membrane stress”) as a clue to graphene oxide’s mechanism of toxicity. [ABSTRACT FROM AUTHOR]

Fiber Bragg gratings are key components for optical fiber sensing applications in harsh environments. This paper investigates the structural and chemical characteristics of femtosecond laser photo-inscribed microvoids. These voids are at the base of type III fs-gratings consisting of a periodic array of microvoids inscribed at the core of an optical fiber. Using high-resolution techniques such as quantitative phase microscopy, electron transmission microscopy, and scattering-type scanning near-field IR optical microscopy, we examined the structure of the microvoids and the densified shells around them. We also investigated the high-temperature behavior of the voids, revealing their evolution in size and shape under step isochronal annealing conditions up to 1250 °C. [ABSTRACT FROM AUTHOR]

In this paper we studied how alloying with different percentages of TiO2 influences the microstructure of Cr2O3 base matrix coatings deposited by plasma spray (APS). Thus, five different types of coatings were made, in which the percentage of TiO2 varied as 0%, 10%, 20%, 30% and 40%. The samples were analysed morphologically both on the surface and in cross-section using direct observation and electron microscopy (SEM). It was observed that none of the TiO2-containing coatings is a simple blend of distinct phases, but are coatings with a specific layered lamellar structure, with coarser and smooth areas, depending on the Ti wt.% presence. All the coatings analysed show micro cracks, porosities and inhomogeneous structure, but with a higher density directly proportional to the percentage of TiO2 in the composition of the coated powder. [ABSTRACT FROM AUTHOR]

The accurate and automated segmentation of neurons in electron microscopy (EM) images presents a challenging problem in neuroscience. In this paper, we propose a deep learning (DL)-based neuron segmentation approach using a relatively shallow residual deconvolutional neural network (DNN) as the core. Our proposed segmentation framework differs from most EM image segmentation networks that use original images as input, as we suggest using modified morphological features with attention characteristics as input instead. We calculate Bhattacharyya distances in morphology feature space to provide attention features, which are then concatenated with the original image and used as input to the segmentation network. By attending to membrane pixels, our network efficiently highlights the discrimination between membrane boundaries and background pixels. To remove noise pixels in the segmentation map while preserving membrane boundaries in the final result, the dilated version of the output is then processed using a guided filtering scenario. Our proposed model outperforms several competing DL methods such as DeepLabv3 as well as different versions of deconvolutional neural networks on the ISBI 2012 dataset in terms of various image segmentation metrics. The proposed attention-based morphological guided framework can help advance research in neuroscience by providing an automated and accurate segmentation of neurons in EM images. [ABSTRACT FROM AUTHOR]

In 1947, the first electron microscope in Spain was installed at the Instituto de Óptica Daza de Valdés (IO-CSIC): an EMU-2A model from the U.S. company RCA. That instrument became what has been called a "frontier instrument, inventor of disciplines"; in this case, electron microscopy. This article analyses the activities of the IO around the microscope, between the end of the Civil War and the beginning of the 1960s. During this time, the Instituto de Óptica was the institution, not the exclusive, but the main promoter of creating a new epistemic community in Spain dedicated to electron microscopy. In this paper, we will focus on analyzing the actors of this development: who they were, how they were formed, and their main motivations. [ABSTRACT FROM AUTHOR]

Abstract: A porcelain body traditionally used to produce ceramic art and design objects was re-formulated using additional waste paper. The aim of this study was to develop knowledge into the technological properties of paper-composite porcelain in its green state, for use within the traditional practices of ceramic art and design production. Characterisation was made by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Two different production methods used by potters, slip casting and free-hand pressing, were used. The presence of the paper fibre, the paper type and the content amount are the important factors in strengthening development. Significant differences were found in relation to the content amount of paper fibre, between the mother porcelain body and the different content amount of paper fibre in the paper-composite porcelain body. [Copyright &y& Elsevier]

Identification of archaeological and historical textile fibres is important because it gives insight into resource management in former times. The arrival of new tools such as table-top scanning electron microscopes, have led to an increased interest in the topic. Unfortunately, there have been cases where a lack of documentation regarding instrument settings and selection criteria has led to questionable conclusions being drawn. Optical and scanning electron microscopy are powerful techniques, but they must be used correctly and with proper knowledge of their limitations. Furthermore, ancient fibre material is often difficult to examine due to issues such as sample degradation, mineralization and the scarcity of material, which means that conclusions based on a statistical analysis of a large number of fibres are essentially not possible. In a cultural heritage context, it is therefore essential to distinguish between characteristic features, by which we mean features that are often, but not always present in a particular species and distinguishing features, which are always present in a particular species and can therefore be used for identification even if only a small amount of sample material can be examined. We argue that the community will have to accept that, quite often, a secure identification is not possible and that absolute statements such as: "This textile is made of flax" will often have to be replaced by relative statements such as "The material is likely to be flax". In this paper, we address these issues as follows: first, we present a fibre identification diagram which can be used, with some limitations, to distinguish between flax, hemp, nettle, jute, hops, and cotton using optical and electron microscopy. We then move on to highlight some of the typical pitfalls of using optical and electron microscopy for fibre identification. Finally, we present measurement documentation tables for optical and electron microscopy images, which we suggest should always be included in publications. Material scarcity means that the amount of material used for investigations should be kept at an absolute minimum. It is thus crucial that results are published with proper documentation so that measurements do not need to be repeated (more material is used) in future studies. It is our hope that the measurement documentation tables will be adapted by the community and used in future publications in the field. The paper finishes with a demonstration example, presenting a fibre analysis of Viking Age textile fragments from the 10th Century with documentation tables. [ABSTRACT FROM AUTHOR]

We review the measurement methods and thickness characterization algorithms of semiconductor multilayer devices. Today’s ultrahigh-density, high-energy-efficient three-dimensional semiconductor devices require an iterative semiconductor layer-stacking process. Accurate determination of nanometer-scale layer thickness is crucial for reliable semiconductor device fabrication. In this paper, we first review the commonly used semiconductor multilayer thickness measurement methods, including destructive and nondestructive measurement methods. Next, we review two approaches for thickness characterization: model-based algorithms using a physical interpretation of multilayer structures and a method using data-driven machine learning. With the growing importance of semiconductor multilayer devices, we anticipate that this study will help in selecting the most appropriate method for multilayer thickness characterization.Highlights: This paper covers various measurement methods and algorithms to detect the thickness of semiconductor multilayer devices. Model-based algorithm is suitable for cases where the number of layers is small or physical interpretation is required. Machine learning performs well for thickness characterization of multilayer devices without complex physical analysis. [ABSTRACT FROM AUTHOR]

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]

Abstract: The addition of a large amount of conductive filler to paper in order to increase electrical conductivity adversely affects some physical properties of the paper. Hence, it is desirable that conductive paper can be manufactured by adding only a small amount of conductive filler. Reinforced paper was manufactured by adding (1) electroless Ag-plated carbon fiber or (2) activated carbon fiber to the pulp. We investigated the effects of adding Ag-plated carbon fiber on the microstructure, physical properties, electrical conductivity, etc., of the paper. We found that the addition of a small amount of Ag-plated carbon fiber to the pulp made it possible to manufacture conductive paper with a high level of electrical conductivity and great physical strength. [Copyright &y& Elsevier]

Abstract: The electrospinning process has been used successfully to fabricate the multiwalled carbon nanotubes (MWCNTs)-embedded polyacrylonitrile (PAN) nanofiber paper. The diameters of nanofibers decreased with increasing CNT concentration. We found large anisotropic electrical conductivity, i.e., the electrical conductivity of the carbonized nanofiber paper along the spinning direction was about three times larger than that normal to the spinning direction, in good contrast with observations that the carbonized PAN nanofiber paper without CNTs did not reveal anisotropy in electrical conductivity. This proves that CNTs in PAN nanofiber were preferentially aligned along the nanofiber axis, in excellent agreements with transmission electron microscopy observations. [Copyright &y& Elsevier]

Background and Aim: Pediculus humanus capitis, the human head louse, remains a global health problem. This study evaluated the resistance of head lice to permethrin and 6-paradol mediated by in vitro detoxification enzyme activity experiments and to describe physical changes in the lice using scanning electron microscopy (SEM). Materials and Methods: The adult stages of P. h. capitis were collected from patients exposed to 1% permethrin and three different concentrations of 6-paradol (0.00005%, 0.0001%, and 0.00015%) using a filter paper diffusion bioassay. Healthy P. h. capitis adults served as the control. The in vitro bioassays were conducted after 10, 20, 30, and 60 min of exposure. The activities of acetylcholinesterase (AChE), glutathione S-transferase (GST), and oxidase were analyzed. Physical changes in the lice were analyzed using SEM. Results: Permethrin and 6-paradol exhibited low toxicity against the lice. At 60 min, 1% permethrin had killed 36.7% of the lice present, while 6-paradol had killed 66.7-86.7%. Permethrin induced significantly elevated AChE, GST, and oxidase activity; 6-paradol also caused significantly elevated AChE, GST, and oxidase activity. Permethrin did not cause any ultrastructural morphological changes on the lice, while 6-paradol severely damaged the head, thorax, respiratory spiracles, and abdomen of the dead lice. Conclusion: This in vitro experimental of P. h. capitis is the first study to report P. h. capitis in East Jakarta shows complete resistance to permethrin and 6-paradol, and to describe the associated increase in AChE, GST, and oxidase activity. It was observed that 6-paradol severely damaged the head, thorax, respiratory spiracles, and abdomen of the dead lice. [ABSTRACT FROM AUTHOR]

Metallic nanoscale particles attract a growing interest in several fields, thanks to their unique bonding characteristics; applications are appearing in the literature in the fields of, for example, sensor coatings and biochemical compound detection. However, the controlled fabrication of such nanopowders is often cumbersome, especially because their characterization is normally slow, involving procedures such as electron microscopy. On the other hand, microwave sensors based on near-field effects on materials are being developed with high sensitivity and show promising characteristics. In this paper, the authors show how a microwave sensor based on a Square Spiral Resonator can be used to characterize paraffin dispersions of nanoparticles conveniently and cost-effectively. [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]

Gold nanoparticles (AuNPs) are extensively used in cellular imaging, single-particle tracking, disease diagnosis, studying membrane protein interaction, and drug delivery. Understanding the dynamics of AuNP uptake in live cells is crucial for optimizing their efficacy and safety. Traditional manual methods for quantifying AuNP uptake are time-consuming and subjective, limiting their scalability and accuracy. The available fluorescence-based techniques are limited to photobleaching and photoblinking. Optical microscopy techniques are limited by diffraction limits. Electron microscopy–based imaging techniques are destructive and unsuitable for live cell imaging. Furthermore, the resulting images may contain hundreds of particles with varied intensities, blurring, and substantial occlusion, making it difficult to manually quantify AuNP uptake. To overcome this issue and measure AuNP uptake by live cells, we annotated a dataset of dark-field images of 50 nanometer–radius AuNPs at different incubation durations. Then, to count the number of particles present in a cell, we created a customized multi-column convolutional neural network (MC-CNN). The customized MC-CNN outperformed typical particle counting architectures when compared to spectroscopy-based counting. This will allow researchers to gain a better understanding of AuNP behavior and interactions with cells, paving the way for advancements in nanomedicine, drug delivery, and biomedical research. The code for this paper is available at the following link: https://github.com/Namerlight/LabelFree_AuNP_Quantification. [ABSTRACT FROM AUTHOR]

Photochemical reduction is used to develop many methods of creating biologically active substances and materials consisting of silver nanoclusters, which makes them relevant for science and technology, including different trends in biotechnology, catalytic systems, label-free quantification, metasurfaces and nanohybrid composites. The paper presents the silver nanoparticle (AgNP) technology based on cavitation-diffusion photochemical reduction in the presence of 10 mg of ligand (polyvinylpyrrolidone) allowing to significantly change the AgNP content depending on the concentration of silver nitrate (AgNO3) in the reaction system, and providing the AgNP domination having a certain size. It is found that at 5 mg of AgNO3 in the reaction system, the size of at least 60% of synthesized nanoparticles, is 26 nm or more, while at 2.5 mg of AgNO3, up to 94.7% of nanoparticles have the size of 15 nm and less, 6 to 10 nm AgNPs being dominated. This meets the need for AgNPs of a certain the size in different fields of science and technology, including medical and pharmaceutical industries, agriculture, and laboratory diagnostics. [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]

In this paper, the possibility of detecting viruses, specifically influenza A virus, based on changes in the spectra of total reflection from macroporous silicon (macro-pSi) films, is demonstrated for the first time. Macro-pSi films with a pore diameter of about 100 nm were produced by electrochemical etching of crystalline silicon substrates. The porosity of the macro-pSi, calculated using the Bruggeman effective medium model, was 75%. Electron microscopy showed that such highly porous films adsorb of 50–100 nm in size viruses on their surface and inside the pores, but the efficiency of adsorption significantly increases when the surface of the nanostructures is functionalized with monoclonal antibodies, providing specific binding of viruses. The reflection spectra of macro-pSi films demonstrate a series of interference fringes, the intensity of which dramatically changes upon virus adsorption. The results obtained demonstrate the possibility of a simple and effective optical method for virus diagnostics using Fabry–Pérot interference in macro‑pSi films. [ABSTRACT FROM AUTHOR]

The method of common lines is a well-established reconstruction technique in cryogenic electron microscopy (cryo-EM), which can be used to extract the relative orientations of an object given tomographic projection images from different directions. In this paper, we deal with an analogous problem in optical diffraction tomography. Based on the Fourier diffraction theorem, we show that rigid motions of the object, i.e., rotations and translations, can be determined by detecting common circles in the Fourier-transformed data. We introduce two methods to identify common circles. The first one is motivated by the common line approach for projection images and detects the relative orientation by parameterizing the common circles in the two images. The second one assumes a smooth motion over time and calculates the angular velocity of the rotational motion via an infinitesimal version of the common circle method. Interestingly, using the stereographic projection, both methods can be reformulated as common line methods, but these lines are, in contrast to those used in cryo-EM, not confined to pass through the origin and allow for a full reconstruction of the relative orientations. Numerical proof-of-the-concept examples demonstrate the performance of our reconstruction methods. [ABSTRACT FROM AUTHOR]

Defects in high performance multi-crystalline silicon wafers can be detrimental to the lifetime of the solar cell. It is, therefore, important to study and understand the underlying structure and chemical elements present at these defective areas in order to suppress them. The underlying cause of the D-band emission line " v e r y i n t e n s e D 3 " (VID3) has not yet been understood, although many theories have been proposed. In this paper, we have investigated the underlying causes of the d-band emission peak VID3 by hyperspectral photoluminescence imaging, scanning electron microscopy, electron backscatter diffraction, scanning transmission electron microscopy, and density functional theory (DFT) to understand the defect structure in areas of a VID3 emission peak in more detail. We found a high VID3 peak intensity at sub-grain and Σ 3 twin boundaries bordering to grains with a small misorientation, which suggests higher stress in these regions. Defects close to the twin boundary indicate a light element dopant in the area, such as oxygen. DFT calculations show that oxygen is prone to segregate to this boundary. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy (SEM) has long been a standard tool for morphological analyses, providing sub micrometer resolution of pharmaceutical formulations. However, analysis of internal morphologies of such formulations can often be biased due to the introduction of artifacts that originate from sample preparation. A recent advancement in SEM, is the focused ion beam scanning electron microscopy (FIB-SEM). This technique uses a focused ion beam (FIB) to remove material with nanometer precision, to provide virtually sample-independent access to sub-surface structures. The FIB can be combined with SEM imaging capabilities within the same instrumentation. As a powerful analytical tool, electron microscopy and FIB-milling are performed sequentially to produce high-resolution 3D models of structural peculiarities of diverse drug delivery systems or their behavior in a biological environment, i.e. intracellular or -tissue distribution. This review paper briefly describes the technical background of the method, outlines a wide array of potential uses within the drug delivery field, and focuses on intracellular transport where high-resolution images are an essential tool for mechanistical insights. [Display omitted] [ABSTRACT FROM AUTHOR]

The paper presents results of transmission electron microscopy of the plasma coating/substrate interface. Its elemental and phase compositions and defect substructure are investigated. The high-speed steel R18-Yu coating is deposited in argon medium onto the type 30HGSA steel substrate high-tempered for several times. It is shown that both the coating and substrate are mutually alloyed. Primarily the substrate demonstrates a multi-phase, multi-element sub-nanoclystalline structure with the lamellar morphology. It is shown that multiple high-temperature tempering leads to the formation of carbide nanoparticles both in the volume and at the boundaries of the martensite lath structure. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) ceramic matrix composite (CMC) cladding is currently being pursued as one of the leading candidates for accident-tolerant fuel (ATF) cladding for light water reactor applications. The morphology of fabrication defects, including the size and shape of voids, is one of the key challenges that impacts cladding performance and guarantees reactor safety. Therefore, quantification of defects' size, location, distribution, and leak paths is critical to determining SiC CMC in-core performance. This research aims to provide quantitative insight into the defect's distribution under multi-scale characterization at different length scales before and after different Transient Reactor Test Facility (TREAT) irradiation tests. A non-destructive multi-scale evaluation of irradiated SiC will help to assess critical microstructural defects from production and/or experimental testing to better understand and predict overall cladding performance. X-ray computed tomography (XCT), a non-destructive, data-rich characterization technique, is combined with lower length scale electronic microscopic characterization, which provides microscale morphology and structural characterization. This paper discusses a fully automatic workflow to detect and analyze SiC-SiC defects using image processing techniques on 3D X-ray images. Following the XCT data analysis, advanced characterizations from focused ion beam (FIB) and transmission electron microscopy (TEM) were conducted to verify the findings from the XCT data, especially quantitative results from local nano-scale TEM 3D tomography data, which were utilized to complement the 3D XCT results. In this work, three SiC samples (two irradiated and one unirradiated) provided by General Atomics are investigated. The irradiated samples were irradiated in a way that was expected to induce cracking, and indeed, the automated workflow developed in this work was able to successfully identify and characterize the defects formation in the irradiated samples while detecting no observed cracking in the unirradiated sample. These results demonstrate the value of automated XCT tools to better understand the damage and damage propagation in SiC-SiC structures for nuclear applications. [ABSTRACT FROM AUTHOR]

This paper deals with the evaluation of the structure of selected hazardous wastes from the production of metals, namely waste from the production of aluminium - red mud and waste from the production of nickel - black nickel mud. In environmental applications, red mud and black nickel mud are likely to be used after activation. The samples were activated using hydrochloric acid to study the structure properties before and after the treatment. Both of these wastes have suitable adsorption and catalytic properties that could be positively affected by the activation of their surfaces. The morphology of the samples was documented by scanning electron microscope, phase analysis was performed using diffraction techniques, and the content of elements was determined by EDX analysis. Also, FTIR analysis of the samples was performed. Activation increases the specific surface area of samples, which is beneficial in many environmental applications, such as in the adsorptive removal of pollutants. Treatment of samples changes the surface properties of the adsorbent, such as electrostatic, hydrophobic, and hydrophilic. The activation creates a new surface structure and thus affects its properties. EDX analysis confirmed the high content of Fe, Al, Si and Ti, which are responsible for good adsorption and catalytic properties. X-ray diffractograms have shown only slight changes in the structure of wastes after activation. The results of SEM confirmed the changes in the surface structure and the creation of new active centres necessary for the successful adsorption process. The FTIR analysis determined the changes in the structure of the samples mainly due to the thermal degradation of C=O and O-Si-O bonds. [ABSTRACT FROM AUTHOR]

Chitin and its derivatives are common natural polymers that are widely used in various technological fields. In recent years, considerable attention has been paid to the preparation of polymer nanocomposites based on metal nanoparticles (NPs). Chitin/chitosan-based composites due to high antibacterial activity are suitable for application in related food storage, textile industries. This paper presents an effective and simple method of obtaining chitosan-chitin copolymer/Ag nanocomposites with an extremely high content of metal nanoparticles. The structure and morphology of the synthesized nanocomposites were investigated using X-ray diffractometry, Fouriertransform infrared spectroscopy, electron microscopy, and their optical properties were studied using UV-VIS spectroscopy as well as spectral ellipsometry. It was ascertained that the resulting nanocomposite films are characterized by a uniform distribution of spherical silver nanoparticles, the sizes of which increase (from 55 up to 143 nm) with increasing the Ag+-ions concentration in the reaction mixtures. The optical absorption spectra of nanocomposites are characterized by the presence of an absorption maximum within the range 458...525 nm, which confirms the formation of Ag NPs. A monotonous increase in the values of the energies of optical transitions was observed in the process of increasing the average size of NPs. [ABSTRACT FROM AUTHOR]

This paper presents an investigation of the oxidation of Alloy X-750 containing 5 wt% iron in a simulated boiling water reactor (BWR) environment. The specimens were exposed by a water jet (10 m/s) at 286 °C for durations ranging from 2 to 840 h, and the development of the oxide microstructure was mainly studied using electron microscopy. The results showed that the oxide scale consists of blocky crystals of trevorite on top of a porous inner layer rich in Ni and Cr. After the longest exposure time, the trevorite crystals completely covered the specimen surface. The study further revealed that the rate at which the oxide grew and the metal dissolved both decreased with time, and the metal thinning process appeared to be sub-parabolic. Given the significant variation in iron content in the X-750 specification, the influence of this element on the material's corrosion performance in BWR was examined by comparing the results from this investigation with those from previous work on material containing 8 wt% Fe. The study demonstrates that the oxide growth, metal dissolution and metal thinning were slower in the material with a higher iron content, indicating the importance of this element in limiting the degradation of Alloy X-750 in BWR environments. [ABSTRACT FROM AUTHOR]

Lateral orientation and aggregation of the graphene sheets limited field enhancement of graphene paper (GP). To improve the field enhancement of GP, argon plasma treatment was induced to destroy the aggregation and cause formation of surface protrusions. After Ar plasma treatment, turn-on field and threshold field of GP were reduced from 2.3 V/μm to 1.6 V/μm and 4.4 V/μm to 3.0 V/μm, respectively. The enhancement was attributed to the protrusions. Scanning electron microscopy and hydrophobicity had been used to prove the morphology change after plasma treatment. [ABSTRACT FROM AUTHOR]

Improvements in machinability by alloying of the workpiece often adversely impact the end user properties of a material. For example, the common use of non-metallic inclusions can lead to improved tool life during turning or milling, but often adversely affects weldability, corrosion, and wear resistance. A cutting tool material meets kilometers of workpiece material during a machining operation. Hence elements in small quantities in the workpiece may insignificantly affect the end user properties but may have large effects on tool wear. One such effect is the formation of refractory and wear resistant reaction products between the workpiece and tool. Such reaction products forming on tool surfaces may lead to improved machinability. This paper proposes the use of small amounts of alloying to induce such a Tool Protection Layer. Additionally, the paper develops a computational framework for designed alloying which balances formation of Tool Protection Layers, its in-process retention, and the functional properties of the alloy. The method has been validated for a case of manganese steel. The calculations were validated first by a wide range of diffusion experiments. Then by industrial turning of cast alloys, by comparing one reference and two newly designed alloys based on the alloying concept. The alloy with 0.003 mol fractions of Al resulted in more than 3 times increase in tool life, due to in-operando formation of Al 2 O 3 Tool Protection Layer. The designed manganese steel maintained its functional properties with respect to abrasive wear resistance and retained its ability to work harden. [Display omitted] • A thermodynamic modeling method for machinability improvement. • Microalloying leads to improved machinability, functional properties maintained. • The formation of alumina tool protection layers increases tool performance. [ABSTRACT FROM AUTHOR]

In the rapidly emerging field of biomedical applications, multifunctional nanoparticles, especially those containing magnetic and plasmonic components, have gained significant attention due to their combined properties. These hybrid systems, often composed of iron oxide and gold, provide both magnetic and optical functionalities and offer promising avenues for applications in multimodal bioimaging, hyperthermal therapies, and magnetically driven selective delivery. This paper focuses on the implementation of advanced characterization methods, comparing statistical analyses of individual multifunctional particle properties with macroscopic properties as a way of fine-tuning synthetic methodologies for their fabrication methods. Special emphasis is placed on the size-dependent properties, biocompatibility, and challenges that can arise from this versatile nanometric system. In order to ensure the quality and applicability of these particles, various novel methods for characterizing the magnetic gold particles, including the analysis of their morphology, optical response, and magnetic response, are also discussed, with the overall goal of optimizing the fabrication of this complex system and thus enhancing its potential as a preferred diagnostic agent. [ABSTRACT FROM AUTHOR]

Ceramic and refractory materials are needed in many fields of activity, necessary for the development of human society, such as steel, non–ferrous metallurgy, chemistry, construction. The raw materials for obtaining refractory products are in short supply on the world market. In the activity carried out by leading economic agents, significant quantities of refractory waste are continuously generated, which must be neutralized and efficiently utilized. In this paper, the authors present the results of experimental research aimed at finalizing a technology for recycling mulcorite waste generated by an economic agent producing porcelain products. The physicochemical characteristics of this type of waste were determined and several technological variants of using mulcorite waste were tested, after an initial processing, in the manufacturing recipes of some pieces of refractory material component of the cast iron casting network from a manufacturer of gray iron castings. After testing eight variants of the composition of the manufacturing recipes, the best variant was chosen, which ensures the use of a maximum percentage of waste but also good values of the quality properties of the products obtained. For this, the main qualitative properties of the finished products were determined by measurements in the laboratory for the absorption coefficient, density and porosity, as well as by optical microscopy investigations on the structure of the finished products. The results of the conducted research demonstrated the possibility of efficient utilization of mulcorite waste, with beneficial effects on manufacturing costs and the environment. [ABSTRACT FROM AUTHOR]

Modern computers are typically heterogeneous devices—besides the standard central processing unit (CPU), they commonly include an accelerator such as a graphics processing unit (GPU). However, exploiting the full potential of such computers is challenging, especially when complex workloads consisting of multiple computationally demanding tasks are to be processed. This paper proposes a framework called Umpalumpa, which aims to manage complex workloads on heterogeneous computers. Umpalumpa combines three aspects that ease programming and optimize code performance. Firstly, it implements a data-centric design, where data are described by their physical properties (e. g., location in memory, size) and logical properties (e. g., dimensionality, shape, padding). Secondly, Umpalumpa utilizes task-based parallelism to schedule tasks on heterogeneous nodes. Thirdly, tasks can be dynamically autotuned on a source code level according to the hardware where the task is executed and the processed data. Altogether, Umpalumpa allows for implementing a complex workload, which is automatically executed on CPUs and accelerators, and allows autotuning to maximize the performance with the given hardware and data input. Umpalumpa focuses on image processing workloads, but the concept is generic and can be extended to different types of workloads. We demonstrate the usability of the proposed framework on two previously accelerated applications from cryogenic electron microscopy: 3D Fourier reconstruction and Movie alignment. We show that, compared to the original implementations, Umpalumpa reduces the complexity and improves the maintainability of the main applications' loops while improving performance through automatic memory management and autotuning of the GPU kernels. [ABSTRACT FROM AUTHOR]

We describe the first truly correlative atomic force micro-scopy-scanning electron microscopy (AFM-SEM) platform designed from first principles and from the ground up for the study of sample properties under a wide range of magnifications. Combining these two microscopy techniques, " in situ ," into a highly integrated workstation opens unprecedented measurement capabilities at the nanoscale, while simplifying experiment workflows to yield a higher level of data throughput. Unlike SEM, the AFM offers true three-dimensional topo-graphy images, something SEM can only provide indirectly. This allows for the characterization of nano-mechanical properties, as well as for magnetic and electrical characterization of samples, which are increasingly of interest in material science, multi-component technologies (that is, solar cell and battery research), and pharmaceutical investigations. On the other hand, the SEM's wide field-of-view is critical in identifying regions of interest with feature sizes of less than a micron, which are notoriously difficult to find over large spatial scales in conventional AFM systems. In addition, the SEM's ability to visualize the AFM tip facilitates its navigation to aid the characterization of samples with challenging three-dimensional topographies. In this paper, we describe the major elements of the system design and demonstrate how correlative microscopy can help the characterization of samples with challenging morphologies such as the edge of a razor blade or the nanomechanical analysis of platinum nanopillars. [ABSTRACT FROM AUTHOR]

In this paper, the microscopy impact on several areas of knowledge is showed through a historical review of microscopy from its origins to the present, follow by a simple description of the optical microscope performance and comparison with the resolving power and cost of the modern electron microscopes. The results of the use of microscopy as a tool to know the microcosm are demonstrated with the important applications that have transcended directly from the scientific to the social field. In conclusion, the window opened by microscopy not only allows us to see beyond the obvious as the fascinating images of the microcosm, but its development has had a transcendental impact on humanity. [ABSTRACT FROM AUTHOR]

In this paper, nickel-clad cubic boron nitride (Ni/c-BN)-reinforced Ni-based composite coating was prepared on the martensitic stainless steel substrate by laser melting technology. The microstructure, phases and properties of the cladding layer were investigated by x-ray diffractometry, scanning electron microscopy, energy-dispersive spectrometry, microhardness test, wear test and potentio-dynamic polarization. The experimental results show that surface quality of the cladding was excellent and free of obvious defects when the Ni/c-BN content was 5 wt.%, while reticulation cracks appeared when the content was higher than 5 wt.%. In addition, compared with the coating without Ni/c-BN, the addition of Ni/c-BN made the coating form a new phase Ni3B and a change in the eutectic tissue in the coating, which was made up of γ-Ni, Ni3B and Ni4B3. After added Ni/c-BN, the hardness, wear resistance, and corrosion resistance of the coating increased first and then decreased. Excess Ni/c-BN reduced the solid solution B element content in the matrix and accelerates the formation of the crack of the coating, thereby deteriorating the hardness, wear resistance and corrosion resistance. The coating had the best hardness, wear resistance and corrosion resistance when the Ni/c-BN content was 5 wt.%. [ABSTRACT FROM AUTHOR]

The modeling of the response of living organisms to a change in environment is an important issue of current interest. An example is the effect of ultraviolet radiation on biological systems. In this paper, molecular and analytical identification of Pseudomonas isolate were reported. Then, swarmer Pseudomonas cells were exposed to UVc radiations. The spatiotemporal response of swarmer Pseudomonas, to UVc exposure, was followed. Observing alterations in bacterial membrane integrity by electron microscopy can help to clarify the detailed mechanisms of resistance to UVc. The most evident changes were related to membrane structures. In the cytoplasm, the main finding was the appearance of round mesosomes as intracellular bilayered membranes. Another impact of UVc on Pseudomonas was evident from the appearance of additional membrane structures. In accordance with the viability results, UVc-induced ultrastructural changes of Pseudomonas membrane structures were identified, resulting in cell death, through a multistage model of UVc inactivation. [ABSTRACT FROM AUTHOR]

This paper deals with the characterisation of cementitious materials from selected cultural heritage structures in Slovenia. The mineralogical–petrographic compositions of an aggregate, a type of binder and secondary minerals were studied via electron microscopy and X-ray powder diffraction. The porosity and pore network were determined using a mercury porosimeter. The results show that the aggregate of the samples was highly diverse, ranging from limestone, dolomite, quartz, feldspar and mica. The binder of the investigated samples was cementitious; either ordinary Portland cement was used, or ordinary Portland cement blended with ground granulated blast furnace slag was used. Some samples consisted of cement–lime binders. The investigated examples entailing cement materials for their construction contribute to a better understanding of the technology used to prepare historical cementitious and cement–lime mixtures. [ABSTRACT FROM AUTHOR]