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A two-level three-factor factorial design experiment was conducted to study the influences of three critical specimen preparation parameters on the measurement results of bitumen by a dynamic shear rheometer (DSR). The investigated factors were (1) the pre-heating temperature (HT) for manufacturing the specimen, (2) the bonding temperature (BT) onto the rheometer, and (3) the trimming (Trim) operation for preparing the specimen after bonding. The analysed data were the measured shear modulus |G*|, phase angle δ, and the characteristic temperatures of bitumen's specific stiffness TX with corresponding phase angle δTX according to the European standard EN 14770:2023. Five types of bitumen were tested, including three penetration grades and two modified bitumen specimens (with polymer and wax additives). In addition, a repeatability evaluation of the test results was conducted. We found that the trimming operation for preparing the specimen has a noticeable impact when using smaller plates (PP08) for the DSR measurement. At higher test temperatures when using larger plates (PP25), the trimming operation does not significantly impact the measured parameters, in contrast to the HT and BT. Except for bitumen type 70/100, modified binders are more susceptible to variation in the analysed parameters than unmodified ones. The three-way interaction Trim:BT:HT tends to cause relatively little variation in measured data. Interactions between two factors Trim:BT, Trim:HT, and BT:HT contribute more to the fluctuation in δ value than in TX and |G*|. The variation employed in this study affects the test repeatability of wax-modified bitumen significantly; however, for unmodified binders the repeatability of TX and δTX are within 0.4–2.1 °C and 0.3–3.1°, respectively. [ABSTRACT FROM AUTHOR]

High‐resolution structures of biomolecules can be obtained using single‐particle cryo‐electron microscopy (SPA cryo‐EM), and the rapidly growing number of structures solved by this method is encouraging more researchers to utilize this technique. As with other structural biology methods, sample preparation for an SPA cryo‐EM data collection requires some expertise and an understanding of the strengths and limitations of the technique in order to make sensible decisions in the sample‐preparation process. In this article, common strategies and pitfalls are described and practical advice is given to increase the chances of success when starting an SPA cryo‐EM project. [ABSTRACT FROM AUTHOR]

Background and Aim: Parasitic infections are a public health problem worldwide, including in Thailand. An epidemiological survey for helminthiasis based on stool examination uses the Kato–Katz method as recommended by the World Health Organization. Limitations of this method include the need for fresh stool, time requirement, and lack of quality control. The aim of this study was to enhance the efficiency of the Kato–Katz technique using formalin and glycerol solutions and to implement specimen preparation in fieldwork. Materials and Methods: For the Kato–Katz method, stool samples were divided into formalin-fixed and unfixed groups at various time points and processes. Fresh echinostome eggs were added to each stool group. Incubation with glycerol increased the clearing process. Each group was observed and photographed using a light microscope. Parasite eggs were imaged and compared using the standard Kato–Katz method. Results: Visualization of echinostome eggs from formalin-fixed stool slides was significantly better than that from unfixed stool slides (p < 0.01). Stool samples fixed for 7 days retained normal echinostome eggs morphology. Incubation with glycerol for 1 h resulted in increased Kato–Katz performance by digesting the stool content and enhancing egg observation. Moreover, the results of the Kato–Katz method using fixed and fixed stool plus glycerol for natural helminth infection showed good quality of Opisthorchis viverrini and Taenia egg visualization and normal morphology with a clear background of slides. Conclusion: Formalin-fixed stool could be more suitable than fresh stool for the Kato–Katz method.

A two-level three-factor factorial design experiment was conducted to study the influences of three critical specimen preparation parameters on the measurement results of bitumen by a dynamic shear rheometer (DSR). The investigated factors were (1) the pre-heating temperature (HT) for manufacturing the specimen, (2) the bonding temperature (BT) onto the rheometer, and (3) the trimming (Trim) operation for preparing the specimen after bonding. The analysed data were the measured shear modulus |G*|, phase angle δ, and the characteristic temperatures of bitumen’s specific stiffness TX with corresponding phase angle δTX according to the European standard EN 14770:2023. Five types of bitumen were tested, including three penetration grades and two modified bitumen specimens (with polymer and wax additives). In addition, a repeatability evaluation of the test results was conducted. We found that the trimming operation for preparing the specimen has a noticeable impact when using smaller plates (PP08) for the DSR measurement. At higher test temperatures when using larger plates (PP25), the trimming operation does not significantly impact the measured parameters, in contrast to the HT and BT. Except for bitumen type 70/100, modified binders are more susceptible to variation in the analysed parameters than unmodified ones. The three-way interaction Trim:BT:HT tends to cause relatively little variation in measured data. Interactions between two factors Trim:BT, Trim:HT, and BT:HT contribute more to the fluctuation in δ value than in TX and |G*|. The variation employed in this study affects the test repeatability of wax-modified bitumen significantly; however, for unmodified binders the repeatability of TX and δTX are within 0.4–2.1 °C and 0.3–3.1°, respectively.

Background and Aim: Parasitic infections are a public health problem worldwide, including in Thailand. An epidemiological survey for helminthiasis based on stool examination uses the Kato-Katz method as recommended by the World Health Organization. Limitations of this method include the need for fresh stool, time requirement, and lack of quality control. The aim of this study was to enhance the efficiency of the Kato-Katz technique using formalin and glycerol solutions and to implement specimen preparation in fieldwork. Materials and Methods: For the Kato-Katz method, stool samples were divided into formalin-fixed and unfixed groups at various time points and processes. Fresh echinostome eggs were added to each stool group. Incubation with glycerol increased the clearing process. Each group was observed and photographed using a light microscope. Parasite eggs were imaged and compared using the standard Kato-Katz method. Results: Visualization of echinostome eggs from formalin-fixed stool slides was significantly better than that from unfixed stool slides (p < 0.01). Stool samples fixed for 7 days retained normal echinostome eggs morphology. Incubation with glycerol for 1 h resulted in increased Kato-Katz performance by digesting the stool content and enhancing egg observation. Moreover, the results of the Kato-Katz method using fixed and fixed stool plus glycerol for natural helminth infection showed good quality of Opisthorchis viverrini and Taenia egg visualization and normal morphology with a clear background of slides. Conclusion: Formalin-fixed stool could be more suitable than fresh stool for the Kato-Katz method. [ABSTRACT FROM AUTHOR]

We combined the traditional and improved technology to prepare the whole skeleton specimen of the adult male greater flamingo (Phoenicopterus roseus) by peeling off the fur, eviscerating, removing the muscle, splitting the skeleton, digesting the residual muscle, degreasing, bleaching, assembling the skeleton and preservation technologies. During the preparation, we used a commercially available 84 disinfectant solution for soft tissue digestion. We also preserved the tendon at the axial joints such as wrist, elbow, and knee joints during the muscle removal process, in order to ensure precise assembly of the large joint contact surfaces or fine sesamoid bones, and we carefully removed the reserved tendon tissue after the skeleton assembly completed. Then the skeleton specimen has complete morphology, bright white appearance, and is easy to preserve for a long time. And this method is suitable for promotion and application. A systematic morphological observation and description of the specimen was also conducted during the preparation, and we found that the skeleton of greater flamingo not only had common characteristics of bird such as lightweight and sturdy, but also had unique characteristics such as the mandible, cervical spine, and hind limb bones to adapt to their diet and wading habits. Furthermore, the collection of skeleton can provide basic information for future research on bird skeletal systems. [ABSTRACT FROM AUTHOR]

Reliable and consistent preparation of atom probe tomography (APT) specimens from aqueous and hydrated biological specimens remains a significant challenge. One particularly difficult process step is the use of a focused ion beam (FIB) instrument for preparing the required needle‐shaped specimen, typically involving a ‘lift‐out’ procedure of a small sample of material. Here, two alternative substrate designs are introduced that enable using FIB only for sharpening, along with example APT datasets. The first design is a laser‐cut FIB‐style half‐grid close to those used for transmission electron microscopy (TEM) that can be used in a grid holder compatible with APT pucks. The second design is a larger, standalone self‐supporting substrate called a ‘crown’, with several specimen positions, which self‐aligns in APT pucks, prepared by electrical discharge machining (EDM). Both designs are made nanoporous, to provide strength to the liquid–substrate interface, using chemical and vacuum dealloying. Alpha brass, a simple, widely available, lower‐cost alternative to previously proposed substrates, was selected for this work. The resulting designs and APT data are presented and suggestions are provided to help drive wider community adoption. [ABSTRACT FROM AUTHOR]

Sodium lauryl ether sulphate (SLES) is a detergent widely used in cosmetics and personal‐care industries; hence, it is of particular interest to study the self‐assembled nanostructure it forms at different conditions. Cryogenic transmission electron microscopy (cryo‐TEM) is the most suitable technique for the direct‐imaging of such systems. However, since SLES is sensitive to flow and shear, specimen preparation artefacts may misrepresent the native state of the solution. In this paper, we present different cryo‐TEM specimen preparation methods, and show how they affect the nanostructure of the system. In fact, for this system, we were able to record the native state of the solution only after sufficient time of on‐the‐grid relaxation (OGR) after blotting. Here, we also intend to point out the importance of considering the nature of the solution when preparing cryo‐TEM specimens. LAY DESCRIPTION: The best method to image structures on the nanoscopic scale, for example, aggregates of tens or hundreds of molecules, is transmission electron microscopy at cryogenic temperatures (below −150°C), known as cryo‐TEM. While this method has become quite widely used, some aspects of specimen preparation for cryo‐TEM, involving the formation of very thin liquid films, which are very rapidly cooled to below −180°C, are not fully understood. In our paper we demonstrate what structural artefacts can be formed during specimen preparation, and show how to avoid them. We use as model systems aqueous solutions of a surfactant ('detergent'), SLES, which is of considerable industrial relevance. [ABSTRACT FROM AUTHOR]

Mine tailings are usually materials with particle sizes in the range of silts, frequently exhibiting very low consistency. This low-consistency condition poses challenges when trying to reconstitute specimens for triaxial testing. The first part of this work presents a description of the main geotechnical properties of mine tailings used in the tests and the difficulties associated with triaxial testing. Next, some developments, in terms of equipment and testing procedure, are presented: the design of a compaction mould, the specimen preparation using moist tamping and the lubricated end platens. Finally, the process of dismantling the specimen using freezing is presented and discussed. The final part of the paper presents some results and summarizes the challenges associated with adapting the equipment and implementing the testing procedures.

Internal erosion is a major threat to the safety and operation of water management structures. Recent failures of embankment dams reported in Australia, Canada, and the US are fresh reminders of the importance of this ongoing issue. Suffusion, the focus of this paper, is one of the main modes of internal erosion occurring in internally unstable soils. It initiates internally, continues slowly with no visible signs, and leads to complete failure if not detected early. Despite recent advances in understanding the influence of suffusion on the mechanical behaviour of internally unstable soils through laboratory investigations, the impact of sample preparation techniques on the soil response during erosion and afterwards is yet to be fully undrstood. When it comes to laboratory investigation of remoulded soils, it has been understood that soil specimens prepared by different techniques show different characteristics and soil fabrics. This research studied the influence of sample preparation methods on the erosion of non-plastic fine particles in internally unstable soils and their mechanical consequences. Soil samples with two gradations, on the borderline of stable and unstable and one fully unstable, were prepared using moist-tamping and wet pluviation techniques and were subjected to a two-hour downward seepage. The erosion progress and pre- and post-erosion drained mechanical behaviour of samples were investigated. Tests result showed a difference in the erodibility of fine particles for the sample on the borderline of internal stability prepared by different techniques, but similar mechanical behaviours for both gradations.

Objective To evaluate the effect of participation in bone and joint specimen preparation on anatomy exam scores and medical students' feedback to the second anatomy classroom. Methods The students of “4+4” program of clinical medicine enrolled in 2021 were divided into experiment and control groups. The students in experiment group were asked to prepare joint specimens under the guidance of teachers in after class time, while the students in control group only required to observe the specimens. The anatomy exam scores of the two groups were analyzed and and questionnaire survey was implemented to collect students' feedback about the joint specimen preparation. Results There was no significant difference in the scores of final examiniation between the experiment group and the control group. However, the lowest and the highest correct rates in experimenl group (40% and 95% respectively) were both higher than that of the control group (32.5% and 82.5% respectively). If the correct rate of joint specimens was calculated separately, the experiment group (87.0%±16.7%) was significantly higher than that of control group (66.7%±24.3%) (P＜0.01). In the limb theory test, the mean score of the experiment group (84.7%±20.5%) was significantly higher than that of the control group (69.3%±14.5%) (P＜0.05). The students gave a high evaluation to the joint specimen preparation in after class time or called second classroom. Conclusions Medical students' participation in joint specimen preparation as the second classroom can improve their learning outcomes and this second classroom strategy as a supplement to the first classroom may be potentiallt shared by other medical schools.

The article deals with DIC (Digital Image Correlation) tests on steel plates used in the automotive and railway industries, as well as in the construction industry. The most critical part of DIC tests is the quality of proper surface preparation, painting, and random patterns. The paint mediates the deformation of the optical systems, and its quality is paramount. The authors' goal in this research is to determine the optimal dye–cleaning–drying time parameters for DIC studies. Commercially available surface preparation and cleaning agents were tested alongside commercially available spray paints. Standard and specific qualification procedures were applied for the measurements. Once the appropriate parameters were determined, the results were validated and qualified by GOM ARAMIS tests. Based on the results, DIC measurements can be performed with higher accuracy and safety in laboratorial and industrial conditions, compared to the traditional deformation measurements executed by dial gauges or linear variable differential transformers. [ABSTRACT FROM AUTHOR]

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Laponite—a synthetic nanoclay with (2:1) layer structure—has shown promise for the improvement of granular deposits susceptible to earthquake induced liquefaction, with much of the work performed in this area relying on testing specimens in which the Laponite is introduced in the sand matrix prior to specimen formation. Field implementation will, however, likely occur through permeation of the porous medium by the Laponite in grout form, and it remains unclear to what degree the results from previous studies can be extrapolated to permeated conditions. This paper presents the results of an experimental program on loose (Dr < 30%) Ottawa sand modified through the addition of small quantities of Laponite (1% by mass of the sand) using two specimen preparation procedures: dry-mixing, in which specimens are formed from sand and Laponite mixed together in dry form; and permeation, in which the Laponite is introduced in the sand matrix in dispersion form after specimen formation. Results of resonant column and monotonic undrained triaxial tests illustrate the effects of the two procedures on the properties of the treated sand over a broad range of strains. The different fabrics generated by the two procedures produce distinct behaviors at small to medium strains. The grain-to-grain bonding previously reported for sand-Laponite specimens is observed only in the dry-mixed specimens. The behavior of the permeated specimens with equivalent Laponite content is controlled by the rheology of the Laponite fluid occupying the pore space at the time of shear, carefully characterized in this study through an extensive program of rheological tests. For these specimens, reduced excess pore pressure and increasingly dilative behavior are observed as the pore fluid develops a gel structure and the yield stress of this gel increases. Independent of specimen preparation technique, all specimens reach the same critical state as the clean sand. [ABSTRACT FROM AUTHOR]

Technological breakthrough in electron microscopy (EM) has started a resolution revolution in EM imaging. Nowadays, the promotion of resolution demands a robust background‐noise‐free EM support for specimen preparation, which is a primary bottleneck of high‐resolution EM imaging. Owing to the atomic thickness and excellent physical properties, graphene has attracted widespread attention in the EM field to achieve high‐resolution multi‐dimensional imaging. However, it is still challenging to prepare high‐quality suspended graphene membranes. Problems like breakage, contamination and wrinkling reduce the quality of suspended graphene membranes, which inhibit their wide and killer applications in EM imaging. In this review, suspended graphene membranes are looked deeply into for multi‐dimensional EM imaging. This study begins with a brief introduction to EM development, followed by a discussion of the synthesis of high‐quality graphene. Then it summarizes various approaches to produce suspended graphene membranes and their killer applications in multi‐dimensional EM characterization, including high‐resolution 2D imaging, cryo‐EM 3D reconstruction, and 4D in situ liquid EM. Based on current achievements, the prospects of graphene membranes for more cutting‐edge applications are finally proposed. [ABSTRACT FROM AUTHOR]

The application of deep learning to spatial transcriptomics (ST) can reveal relationships between gene expression and tissue architecture. Prior work has demonstrated that inferring gene expression from tissue histomorphology can discern these spatial molecular markers to enable population scale studies, reducing the fiscal barriers associated with large-scale spatial profiling. However, while most improvements in algorithmic performance have focused on improving model architectures, little is known about how the quality of tissue preparation and imaging can affect deep learning model training for spatial inference from morphology and its potential for widespread clinical adoption. Prior studies for ST inference from histology typically utilize manually stained frozen sections with imaging on non-clinical grade scanners. Training such models on ST cohorts is also costly. We hypothesize that adopting tissue processing and imaging practices that mirror standards for clinical implementation (permanent sections, automated tissue staining, and clinical grade scanning) can significantly improve model performance. An enhanced specimen processing and imaging protocol was developed for deep learning-based ST inference from morphology. This protocol featured the Visium CytAssist assay to permit automated hematoxylin and eosin staining (e.g. Leica Bond), 40×-resolution imaging, and joining of multiple patients' tissue sections per capture area prior to ST profiling. Using a cohort of 13 pathologic T Stage-III stage colorectal cancer patients, we compared the performance of models trained on slide prepared using enhanced versus traditional (i.e. manual staining and low-resolution imaging) protocols. Leveraging Inceptionv3 neural networks, we predicted gene expression across serial, histologically-matched tissue sections using whole slide images (WSI) from both protocols. The data Shapley was used to quantify and compare marginal performance gains on a patient-by-patient basis attributed to using the enhanced protocol versus the actual costs of spatial profiling. Findings indicate that training and validating on WSI acquired through the enhanced protocol as opposed to the traditional method resulted in improved performance at lower fiscal cost. In the realm of ST, the enhancement of deep learning architectures frequently captures the spotlight; however, the significance of specimen processing and imaging is often understated. This research, informed through a game-theoretic lens, underscores the substantial impact that specimen preparation/imaging can have on spatial transcriptomic inference from morphology. It is essential to integrate such optimized processing protocols to facilitate the identification of prognostic markers at a larger scale., (© The Author(s) 2024. Published by Oxford University Press.)

Appropriate rock characterization is beneficial in providing a reliable judgment on rock properties which is crucial for the design process of rock engineering applications. However, it can be difficult to obtain consistent mechanical parameters due to substantial variations in rock properties. In this research, uniaxial compression tests on dolerite specimens collected from a gold mine in Western Australia showed substantial scatter in the results. Rock categorization based on the P-wave velocities is as accurate as the thin section analysis, which suggests that they can be used together to gain a more accurate initial understanding of the rock types before any laboratory testing. The quality of specimen preparation and rock–machine interaction greatly affect the test results. For instance, non-parallelness of loading platens can lead to considerable scatter of the testing results, which would be perceived as rock variability. It is suggested that the current testing standards should be modified towards a better control of the loading machine performance and equipment precision. Finally, the possibility of pre-existing microcracks in rock, neither detected by the thin section analysis nor by the ultrasonic measurement, must be examined by computed tomography (CT) scanning as they can affect the test results. This study will enhance our knowledge about the sources of variability in laboratory test results of rock which is essential for obtaining reliable data.

Vestibular organs consist of the maculae staticae, which are located in both the utricle and saccule, as well as the semicircular ducts and their ampullas. There have been no reports on specimen preparation methods for vestibular organs, including maculae staticae or semicircular ducts. In this study, we investigated highly reproducible methods of preparing vestibular organ specimens for histopathological examinations. We established a method that allows researchers to observe the utricle and saccule, including otoliths, the ampulla of a semicircular duct, and parts of semicircular ducts. This highly reproducible method is useful for histopathological analysis of mice with symptoms of abnormal equilibrium caused by medical toxicity and genetic modification. [ABSTRACT FROM AUTHOR]

Abstract Single-cell RNA sequencing (scRNA-seq) is a tool for studying gene expression at the single-cell level that has been widely used due to its unprecedented high resolution. In the present review, we outline the preparation process and sequencing platforms for the scRNA-seq analysis of solid tumor specimens and discuss the main steps and methods used during data analysis, including quality control, batch-effect correction, normalization, cell cycle phase assignment, clustering, cell trajectory and pseudo-time reconstruction, differential expression analysis and gene set enrichment analysis, as well as gene regulatory network inference. Traditional bulk RNA sequencing does not address the heterogeneity within and between tumors, and since the development of the first scRNA-seq technique, this approach has been widely used in cancer research to better understand cancer cell biology and pathogenetic mechanisms. ScRNA-seq has been of great significance for the development of targeted therapy and immunotherapy. In the second part of this review, we focus on the application of scRNA-seq in solid tumors, and summarize the findings and achievements in tumor research afforded by its use. ScRNA-seq holds promise for improving our understanding of the molecular characteristics of cancer, and potentially contributing to improved diagnosis, prognosis, and therapeutics.

Specimen preparation methods significantly affect indoor sand soil's properties. A theoretical model was developed based on granular thermodynamics to describe the undrained shear characteristics of calcareous sand. We validated the model using specimens prepared through four different methods under various relative densities, stress paths, and confining pressures. The hardening index and granular temperature of this model effectively reflect the impact of specimen preparation methods on the strength characteristics of calcareous sand. The model successfully captured these differences in shear behavior resulting from four preparation methods by adjusting the hardening parameters. Furthermore, this model can accurately describe the influence of stress path changes on the mechanical responses of the calcareous sand granular system by incorporating the third elastic strain invariant. [ABSTRACT FROM AUTHOR]

Cryogenic electron microscopy has become an essential tool for structure determination of biological macromolecules. In practice, the difficulty to reliably prepare samples with uniform ice thickness still represents a barrier for routine high-resolution imaging and limits the current throughput of the technique. We show that a nanofluidic sample support with well-defined geometry can be used to prepare cryo-EM specimens with reproducible ice thickness from picoliter sample volumes. The sample solution is contained in electron-transparent nanochannels that provide uniform thickness gradients without further optimisation and eliminate the potentially destructive air-water interface. We demonstrate the possibility to perform high-resolution structure determination with three standard protein specimens. Nanofabricated sample supports bear potential to automate the cryo-EM workflow, and to explore new frontiers for cryo-EM applications such as time-resolved imaging and high-throughput screening.

Cryogenic atom probe tomography (cryo-APT) is being developed to enable nanoscale compositional analyses of frozen liquids. Yet, the availability of readily available substrates that allow for the fixation of liquids while providing sufficient strength to their interface is still an issue. Here, we propose the use of 1-2-µm-thick binary alloy film of gold-silver sputtered onto flat silicon, with sufficient adhesion without an additional layer. Through chemical dealloying, we successfully fabricate a nanoporous substrate, with an open-pore structure, which is mounted on a microarray of Si posts by lift-out in the focused-ion beam system, allowing for cryogenic fixation of liquids. We present cryo-APT results obtained after cryogenic sharpening, vacuum cryo-transfer, and analysis of pure water on the top and inside the nanoporous film. We demonstrate that this new substrate has the requisite characteristics for facilitating cryo-APT of frozen liquids, with a relatively lower volume of precious metals. This complete workflow represents an improved approach for frozen liquid analysis, from preparation of the films to the successful fixation of the liquid in the porous network, to cryo-APT., Competing Interests: Conflict of Interest. The authors declare no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Microscopy Society of America.)

We describe an experimental approach for achieving an optimal black background for scanning electron photomicrographs of small samples with elaborate and intricate structures. Specimens of the highly ornate, 66-million-year-old chorate dinoflagellate cyst species Cannosphaeropsis franciscana were selected as the subject of this study. Photomicrographs collected following standard aluminum stub surface placement were compared to those taken of specimens mounted using a novel pin-and-pedestal method. This simplistic mounting technique minimizes the need for post-production image editing and extraneous background removal. [ABSTRACT FROM AUTHOR]

Single-cell RNA sequencing (scRNA-seq) is a tool for studying gene expression at the single-cell level that has been widely used due to its unprecedented high resolution. In the present review, we outline the preparation process and sequencing platforms for the scRNA-seq analysis of solid tumor specimens and discuss the main steps and methods used during data analysis, including quality control, batch-effect correction, normalization, cell cycle phase assignment, clustering, cell trajectory and pseudo-time reconstruction, differential expression analysis and gene set enrichment analysis, as well as gene regulatory network inference. Traditional bulk RNA sequencing does not address the heterogeneity within and between tumors, and since the development of the first scRNA-seq technique, this approach has been widely used in cancer research to better understand cancer cell biology and pathogenetic mechanisms. ScRNA-seq has been of great significance for the development of targeted therapy and immunotherapy. In the second part of this review, we focus on the application of scRNA-seq in solid tumors, and summarize the findings and achievements in tumor research afforded by its use. ScRNA-seq holds promise for improving our understanding of the molecular characteristics of cancer, and potentially contributing to improved diagnosis, prognosis, and therapeutics. [ABSTRACT FROM AUTHOR]

Blotting times for conventional cryoEM specimen preparation complicate time‐resolved studies and lead to some specimens adopting preferred orientations or denaturing at the air–water interface. Here, it is shown that solution sprayed onto one side of a holey cryoEM grid can be wicked through the grid by a glass‐fiber filter held against the opposite side, often called the 'back', of the grid, producing a film suitable for vitrification. This process can be completed in tens of milliseconds. Ultrasonic specimen application and through‐grid wicking were combined in a high‐speed specimen‐preparation device that was named 'Back‐it‐up' or BIU. The high liquid‐absorption capacity of the glass fiber compared with self‐wicking grids makes the method relatively insensitive to the amount of sample applied. Consequently, through‐grid wicking produces large areas of ice that are suitable for cryoEM for both soluble and detergent‐solubilized protein complexes. The speed of the device increases the number of views for a specimen that suffers from preferred orientations. [ABSTRACT FROM AUTHOR]

Investigation of solid electrolyte interphases (SEIs) on negative electrode surfaces is essential to improve the stable charge-discharge performance of rechargeable lithium-air batteries (Li-O2 batteries). In this study, a direct investigation of SEI films is conducted using analytical transmission electron microscopy (TEM). A thin Cu specimen is prefabricated for TEM observation and is utilised as a model substrate for SEI formation. The electrochemical cell constructed using dissolved oxygen in the electrolyte exhibits a greater electrochemical overpotential during the Li-metal deposition process than that constructed with a pristine electrolyte. This suggests that different electrochemical passivation features occur in each different electrochemical cell. TEM observation confirms that the surface film formed by O2 dissolute electrolyte is a polycrystalline Li2O film with a thickness of ~5 nm, whereas the film formed by the pristine electrolyte is organic-based, amorphous-like and 20–50 nm thick. The dissolved oxygen molecules are more easily reduced than the components of the electrolyte, leading to the formation of Li2O as a stable passivation SEI film, which is expected to exhibit good charge-discharge features during the operation of the Li-O2 battery. [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]

This paper presents the effect of blade type and feeding force during resin-bonded dentin specimen preparation on the microtensile bond strength (μTBS) test. Forty resin-bonded flat middle dentin specimens were divided into four groups. The specimens of each group were sectioned according to type of blade and feeding force as follows: fine grit/20 N, fine grit/40 N, medium grit/20 N, and medium grit/40 N to obtain resin-dentin sticks with a cross-sectional area of 1.0 mm2. Four sticks from the center of each tooth were subjected to the μTBS test. Five remaining sticks of each group were selected for surface topography observation under a scanning electron microscope (SEM). As a result, the bond strength of the medium-grit group was higher than that of the fine-grit group (p < 0.001), whereas the feeding force had no influence on bond strength values (p = 0.648). From the SEM, sticks prepared with the fine-grit blade showed a smoother surface integrity and fewer defects on the specimen edges in comparison with the sticks prepared with the medium-grit blade. The grit type of the blade is one of the considerable factors that may affect the bond strength and the surface integrity of resin-dentin specimens for microtensile testing.

The shear behavior of soils is typically related to the state of the soil in terms of the initial global void ratio and effective confining stress. However, laboratory tests on reconstituted sand specimens have shown that the shear behavior is also dependent upon the specimen preparation method. This paper describes the findings of a series of studies, which quantitatively evaluated the differences in the inherent microstructure of dilatant sand specimens prepared by air pluviation, moist tamping and water deposition. Quantitative measures such as local void ratio distribution, local void ratio distribution entropy and particle orientation entropy were found to be dependent on the preparation method. Microstructure evolution in the sand specimens during triaxial compression testing was also investigated. Measuring global properties of the specimens was shown to mask the complex and evolving internal conditions during shear. The global response was found to be strongly dependent on the shear induced microstructure which in turn was directly influenced by the preparation method dependent inherent microstructure. [ABSTRACT FROM AUTHOR]

This paper presents the experimental techniques of transmission electron microscopy of plasma-spray powder alloy coatings. It includes the specimen preparation techniques for powder materials and for plasma spray powder coatings from the nickel-chromium-based alloy and synthetic hydroxyapatite (HA) and the analysis of the results. The study of the structure-phase compositions of HA powders and HA and Ni-Cr-based plasma spray coatings has been carried out by using transmission electron microscopy on JEM-2100 (JEOL), and by X-ray diffraction (XRD) on X’Pert PRO diffractometer (PANalytical, the Netherlands). It has been established that the coatings have the desired structure-phase composition as a result of the selection of specific modes of plasma spraying and additional plasma treatment. The advantages and challenges of application of TEM method for analyzing the structure of thick (up to 300 μm) powder coatings deposited by plasma spraying methods onto metal substrates are investigated. [ABSTRACT FROM AUTHOR]

Advances in TEM's performance as well as in materials being investigated require the relevant improvement in sample preparation technology. For a long period of time TEM investigations of metals have been successfully performed using the electrochemical jet polishing method for the sample preparation, i.e. thinning. This classical approach has proved to be unsatisfactory in the case of electrically not conductive and/or multiphase materials – for instance various kinds of ceramics and composites. A milestone in solving this problem has been an elaboration of ion milling. Overcoming certain disadvantages of this technology, mainly sample damage, as well as providing site specificity of the sampling procedure, has been achieved owing to the onset and development of the focused ion beam (FIB) method. The current paper presents the authors' own experience in the preparation of TEM specimens of conventional WC-Co type and experimental WC-Ni based supercoarse sintered carbides. These metal matrix composites consist of large (ca. 10 μm) tungsten carbide particles and a binding metal phase (cobalt or nickel based). Because of the pronounced microstructural, mechanical and electrochemical inhomogeneity, as well as the size of hard WC particles, traditional (mechanical, jet polishing, electrochemical) procedures proved to be totally inadequate. Therefore multi stage lift-out procedure employing a focused beam of gallium ions of various energy ( in situ lift-out of the sample plus H-bar geometry final thinning) and argon ion polishing aimed at the removal of the damaged (defected and amorphous) layer has been elaborated and successfully applied. A large number of defects in the WC particles (dislocations, stacking faults) and within the matrix areas (dislocations, microtwins) as well as high quality of the WC-metal matrix interfaces were found. [ABSTRACT FROM AUTHOR]

Cementitious Repair Materials (CRMs) in the construction industry have been used for many decades now and has become a very important part of activities in cement world. The performance of some of these CRMs when applied to retrofitting concrete structural elements is also well documented. However, the characterization of some of the CRMs at the micro- and nano level is not fully documented. The first step to studying materials at the microscopic level is to be able to fabricate proper specimens for microscopy. In this study, a special and newly developed class of CRM was selected and fabricated by Focused Ion Beam (FIB) using well-known “Lift-out” technique. The prepared specimen was later examined using various analytical techniques such as energy dispersive x-ray analysis using one of the highest and most stable Scanning Transmission Electron Holography Microscopy (STEHM) around the world. This process enabled understanding of the composition, morphology, and spatial distribution of various phases of the CRM. It was observed that the microstructure consisted of a very fine, compact, and homogenous amorphous structure. X-ray analysis indicated that there was considerable deviation between the Si/Ca ratios for the hydrated product. [ABSTRACT FROM AUTHOR]

We present a specimen preparation procedure for atom-probe tomography using SemGlu from Kleindiek Nanotechnik, an adhesive that hardens under electron beam irradiation. The SemGlu adhesive is used in place of focused-ion-beam-induced deposition of organo-metallic Pt, W, or C to form a bond between the sample and the substrate during the specimen preparation procedure. We demonstrate the utility of this adhesive-based specimen preparation technique with a correlated atom-probe tomography-scanning transmission electron microscopy study of the iron-nickel alloy kamacite (ferrite, ɑ-iron) in the Bristol iron meteorite and two steel specimens. [ABSTRACT FROM PUBLISHER]

Portland cement can be mixed with sand to improve its mechanical characteristics. Considering the inherent anisotropy of most sands, it is not clear whether the added cement shall contribute to equal increases in strength and stiffness in vertical and horizontal directions or not. Literature review reveals that all the previous experimental studies on the cement-treated soil topics are limited to conventional triaxial device test results. The effect of cement addition to clean sand in more sophisticated stress-path controlled devices like "Simple Shear Apparatus" (SSA) and "Hollow Cylinder Apparatus" (HCA) for simulating more realistic loading conditions, such as earthquake, have not been investigated yet. This paper presents innovative methods for testing artificially cemented sands through making modifications to the loading platens, specimen molds, and specimen preparation methods of SSA and HCA. Undrained tests under different monotonic stress paths were carried out on different mixtures of Portland cement with clean sand to investigate the effect of principal stress rotations. The test results revealed that the cement mixture reduces the anisotropy, while it improves the mixture mechanical properties compared to the compacted uncemented sand. [ABSTRACT FROM AUTHOR]