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This research aims to identify the prevalence of failure for Birmingham Hip Prosthesis (BHR) in total hip arthroplasty and to analyze its reasons from biomaterials and biofunctional perspectives. We present our current analysis and tests on a series of different BHR-retrieved prostheses after premature failure. Relevant clinical data, such as X-ray investigations and intraoperative images for clinical case studies, were analyzed to better understand all factors involved in BHR prosthesis failure. A detailed analysis of the failures highlighted uneven cement distribution, overloading in certain areas, and void formation in the material. A closer investigation using microscopical techniques revealed the presence of a crack originating from the gap between the cement mantle and human bone. Additionally, scanning electron microscopy analyses were conducted as part of the investigation to examine bone cement morphology in detail and better understand the interactions at the interfaces between implant, cement, and bone. In conclusion, this research emphasizes the importance of surgical technique planning and the cementation procedure in the success rate of BHR prostheses. It also underscores the need to carefully evaluate patient characteristics and bone quality to minimize the risk of BHR prosthesis failure. The cementation procedure seems to be essential for the long-term functionality of the BHR prosthesis. [ABSTRACT FROM AUTHOR]

Until the late 20th century, the idea of identifying wildfires in deep time was not generally accepted. One of the basic problems was the fact that charcoal-like wood fragments, so often found in sedimentary rocks and in coals, were termed fusain and, in addition, many researchers could not envision wildfires in peat-forming systems. The advent of Scanning Electron Microscopy and studies on modern charcoals and fossil fusains demonstrated beyond doubt that wildfire residues may be recognized in rocks dating back to at least 350 million years. Increasing numbers of studies on modern and fossil charcoal assemblages from the 1970s through the 1990s established the potential importance of wildfires in the fossil record, using Carboniferous examples in particular. Since the 1990s, extensive progress has been made in understanding modern wildfires and their byproducts. New techniques to study ancient charcoals have allowed considerable progress to be made to integrate modern and ancient fire studies, both before and after the evolution of mankind. Four important developments have made a reassessment of Carboniferous wildfires necessary: the recognition of the role of atmospheric oxygen in controlling the occurrence of wildfire; the development of new microscopical techniques allowing more detailed anatomical data to be obtained from charcoal; the integration of molecular studies with the evolution of fire traits; and new developments in or understanding of post-fire erosion/deposition systems. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surface sizing (or coating) can significantly improve surface properties and enhance the writing performance of paper products. Pickering emulsion, where the solid particles are used, is applied as a sizing agent due to its insensitivity to external environment and narrow size distributions. This research investigated the writing and printing effect on Xuan paper (a kind of porous handmade paper originating in ancient China used for writing and painting) coated with Pickering emulsion. The morphology and narrow size distribution of alkenyl succinic anhydride-in-water emulsions were characterized by microscopical techniques. Subsequently, these emulsions were applied for surface sizing on Xuan paper, and the surface properties of the sized paper were analyzed by pH values. The obtained data indicates that a series of alkaline-sized paper are successfully produced. The results of static contact angles, whiteness, Fourier transform infrared spectroscopy, and scanning electron microscopy reveal that Pickering emulsion provides a smooth surface for writing on Xuan paper, without significantly changing the whiteness of the paper or affecting the writing quality. In addition, the ink droplets on coated Xuan paper and their diffusion dynamics were recorded and quantitatively described by the radial mean distribution function, which allowed for the simultaneous determination of the diffusion radius, color intensity, diffusion roundness, and spread rate. This work introduces a fresh perspective on the correlation between the paper's macroscopic properties and writing parameters, and it further enriches the comprehension of Pickering emulsion systems. In addition, this study presents an overview of the theoretical and practical implications of developing a quantitative model for describing writing patterns and providing a novel approach for surface technology, image description, and hydrodynamic diffusion in porous media. [ABSTRACT FROM AUTHOR]

The moss genus Ctenidium (Schimp.) Mitt. comprises approximately 23 species worldwide, of which two are known to exist in Hawai'i. Based on recent molecular studies, the genus has been reclassified into the family Myuriaceae, departing from its traditional classification in the Hypnaceae. Plants newly collected from Maui exhibit most characteristics of Ctenidium but differ from all known species within the genus by a combination of several critical characters detailed in this study. Consequently, we propose the classification of this moss as a new species of Ctenidium. The material was studied in Hoyer's solution, using standard microscopical and photomicrographical techniques. Ctenidium multiseriatum S.He & M.K.Thomas is described as a new species from Hawai'i and distinguished from all known Ctenidium species by a combination of distinctive characters including multiseriate paraphyses, clearly prorate laminal cells at both the upper and the lower ends, shorter median and upper laminal cells, ecostae perichaetial leaves with subentire margins, irregularly subpinnately branched stems, and foliose pseudoparaphyllia. [ABSTRACT FROM AUTHOR]

Summary: The endomembrane system consists of various membrane‐bound organelles including the endoplasmic reticulum (ER), Golgi apparatus, trans‐Golgi network (TGN), endosomes, and the lysosome/vacuole. Membrane trafficking between distinct compartments is mainly achieved by vesicular transport. As the endomembrane compartments and the machineries regulating the membrane trafficking are largely conserved across all eukaryotes, our current knowledge on organelle biogenesis and endomembrane trafficking in plants has mainly been shaped by corresponding studies in mammals and yeast. However, unique perspectives have emerged from plant cell biology research through the characterization of plant‐specific regulators as well as the development and application of the state‐of‐the‐art microscopical techniques. In this review, we summarize our current knowledge on the plant endomembrane system, with a focus on several distinct pathways: ER‐to‐Golgi transport, protein sorting at the TGN, endosomal sorting on multivesicular bodies, vacuolar trafficking/vacuole biogenesis, and the autophagy pathway. We also give an update on advanced imaging techniques for the plant cell biology research. [ABSTRACT FROM AUTHOR]

Various chalcidoid wasps can actively steer their terebra (= ovipositor shaft) in diverse directions, despite the lack of terebral intrinsic musculature. To investigate the mechanisms of these bending and rotational movements, we combined microscopical and microtomographical techniques, together with videography, to analyse the musculoskeletal ovipositor system of the ectoparasitoid pteromalid wasp Lariophagus distinguendus (Förster, 1841) and the employment of its terebra during oviposition. The ovipositor consists of three pairs of valvulae, two pairs of valvifers and the female T9 (9th abdominal tergum). The paired 1st and the 2nd valvulae are interlocked via the olistheter system, which allows the three parts to slide longitudinally relative to each other, and form the terebra. The various ovipositor movements are actuated by a set of nine paired muscles, three of which (i.e. 1st valvifer-genital membrane muscle, ventral 2nd valvifer-venom gland reservoir muscle, T9-genital membrane muscle) are described here for the first time in chalcidoids. The anterior and posterior 2nd valvifer-2nd valvula muscles are adapted in function. (1) In the active probing position, they enable the wasps to pull the base of each of the longitudinally split and asymmetrically overlapping halves of the 2nd valvula that are fused at the apex dorsally, thus enabling lateral bending of the terebra. Concurrently, the 1st valvulae can be pro- and retracted regardless of this bending. (2) These muscles can also rotate the 2nd valvula and therefore the whole terebra at the basal articulation, allowing bending in various directions. The position of the terebra is anchored at the puncture site in hard substrates (in which drilling is extremely energy- and time-consuming). A freely steerable terebra increases the chance of contacting a potential host within a concealed cavity. The evolution of the ability actively to steer the terebra can be considered a key innovation that has putatively contributed to the acquisition of new hosts to a parasitoid's host range. Such shifts in host exploitation, each followed by rapid radiations, have probably aided the evolutionary success of Chalcidoidea (with more than 500,000 species estimated). [ABSTRACT FROM AUTHOR]

Single-molecule microscopy has become an indispensable tool for biochemical analysis. The capability of characterizing distinct properties of individual molecules without averaging has provided us with a different perspective for the existing scientific issues and phenomena. Recently, super-resolution fluorescence microscopy techniques have overcome the optical diffraction limit by the localization of molecule positions. However, the labeling process can potentially modify the intermolecular dynamics. Based on the highly sensitive nanomechanical photothermal microscopy reported previously, we propose optimizations on this label-free microscopy technique toward localization microscopy. A localization precision of 3 Å is achieved with gold nanoparticles, and the detection of polarization-dependent absorption is demonstrated, which opens the door for further improvement with polarization modulation imaging. [ABSTRACT FROM AUTHOR]

To the best of the authors' knowledge, this study is one of its kind since it is related to the quantitative shape examination of particles of feed, concentrate, middling and tailing products in coarse and fine shaking table streams of a Turkish chromite concentration plant. In this study, the novel technique; Dynamic image analysis (DIA) as well as visual inspection by SEM and stereomicroscope were used for the representative samples of the plant. Analysis revealed that particle shapes of concentrate products are mostly equant or round while the most elongated particles were observed in tailing products at a 95% confidence level. This is highly linked to the rolling and sliding movement of round and elongated particles, respectively on the deck. This implies that particle shape is one of the parameters affecting gravity separation. Using shape data with tonnages of the circuits in mass balance equations indicates that shape distributions of products in table circuits are consistent. This study gives insight as better separation recovery could be obtained when a proper mill is used for producing feed particles, which have targeted shape to shaking tables since any improvements in recovery will have a big effect on the concentrate income. [ABSTRACT FROM AUTHOR]

Since it was first demonstrated in 1987, magnetic force microscopy (MFM) has become a truly widespread and commonly used characterization technique that has been applied to a variety of research and industrial applications. Some of the main advantages of the method includes its high spatial resolution (typically ∼50 nm), ability to work in variable temperature and applied magnetic fields, versatility, and simplicity in operation, all without almost any need for sample preparation. However, for most commercial systems, the technique has historically provided only qualitative information, and the number of available modes was typically limited, thus not reflecting the experimental demands. Additionally, the range of samples under study was largely restricted to "classic" ferromagnetic samples (typically, thin films or patterned nanostructures). Throughout this Perspective article, the recent progress and development of MFM is described, followed by a summary of the current state-of-the-art techniques and objects for study. Finally, the future of this fascinating field is discussed in the context of emerging instrumental and material developments. Aspects including quantitative MFM, the accurate interpretation of the MFM images, new instrumentation, probe-engineering alternatives, and applications of MFM to new (often interdisciplinary) areas of the materials science, physics, and biology will be discussed. We first describe the physical principles of MFM, specifically paying attention to common artifacts frequently occurring in MFM measurements; then, we present a comprehensive review of the recent developments in the MFM modes, instrumentation, and the main application areas; finally, the importance of the technique is speculated upon for emerging or anticipated to emerge fields including skyrmions, 2D-materials, and topological insulators. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) techniques such as laser powder bed fusion (L-PBF) are rapidly growing due to the inherent design freedom and possibilities to produce components not available with other techniques. This could be utilized in, e.g., the design of new types of heat exchangers in ferritic stainless steels often used for high-temperature applications. Ferritic stainless steels are, however, difficult to weld and could therefore imply obstacles when produced by AM. When establishing the AM-produced alloy in new applications, it is therefore important to increase the understanding of the mechanical properties and high-temperature creep resistance in relation to the unique microstructure and printability. In this study, we have investigated the microstructure of Cr-rich SS446 ferritic stainless steel produced by L-PBF by microscopical and crystallographic techniques. The properties were compared to the conventionally produced tubes. The rapid cooling and reheating during the application of the subsequent powder layers during L-PBF introduces an intriguing microstructure consisting of a ferritic matrix with precipitation of austenite showing a Kurdjumov–Sachs orientation relationship. Characteristic dislocation networks were observed in the L-PBF samples and contributed to the good mechanical properties in the as-built state (more than twice the yield strength of the conventionally produced tube). Furthermore, the creep resistance at 800 °C was superior to the conventionally produced component, suggesting that L-PBF-produced SS446 possesses many advantages regarding production as compared to the conventional route. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium spp. are protozoan parasites that cause diarrhea in humans and animals. Subtyping data about Cryptosporidium spp. in Isfahan, Iran is limited; therefore, we aimed to study the prevalence rate of Cryptosporidium spp. in cancer patients, associated risk factors, and subtypes of Cryptosporidium spp. Methods: Fecal samples were collected from 187 cancer patients from the Oncology Department of Seyed-al-Shohada Hospital, Isfahan University of Medical Sciences during 2014-2020 and screened for Cryptosporidium spp. using microscopical techniques. Nested PCR amplifying 18S rRNA gene was used to detect Cryptosporidium spp. in samples, followed by subtyping using nested PCR amplifying gp60 sequences. Results: Overall, the rate of infection with Cryptosporidium spp. was 4.3% (n=8). Five samples out of eight samples were identified as Cryptosporidium spp. using a nested PCR for the 18S rRNA gene, two subtypes of C. parvum named IIaA18G3R1 (n = 2) and IIaA17G2R1 (n = 2), and one subtype of C. hominis named IbA6G3 were identified by sequencing of the gp60. The IbA6G3 subtype has rarely been detected in other investigations. Conclusion: This is the first survey on the subtyping of Cryptosporidium spp. in this region. The results of the present survey show both zoonotic and anthroponotic transmission routes in the region. [ABSTRACT FROM AUTHOR]

By combining top-down lithographic techniques with the meniscus-force deposition method, hierarchical structures consisting of defined regular elements on length scales from a few tens of nanometers to millimeters can be assembled out of magnetic nanoparticles. Varying the size and shape of the regular elements and distance between them offers the possibility to study magnetic coupling phenomena on three different length scales. As an example, we study hierarchical arrangements of magnetite nanoparticles (Fe3O4) with a diameter of d=20 nm by ferromagnetic resonance measurements and demonstrate that the macroscopic properties of the structures are dominated by the assemblies of densely packed nanoparticles on the sub lm scale rather than by the interactions between these assemblies which are arranged on a grid with lm spacings or than by the macroscopic outer shape of the grid on the mm scale. [ABSTRACT FROM AUTHOR]

The Malvern Mastersizer 3000 laser particle size analyzer and HydroMV wet sampler were used, and the parameters are set as follows: sample refractive index 1.52, funnel width 2.0mm, dispersion air pressure 4.0 bar, ultrasonic intensity 50%, ultrasonic time 30s, stirring speed 1600rpm, laser obscuration 8% - 15%. The mean values of particle size distribution d (0.1), d (0.5), and d (0.9) of 3 batches of tadalafil drug substance were 0.819 μm, 2.79 μm, and 8.44 μm, respectively. The measured results were basically consistent with the microscopic method. The method is simple, accurate and precise, and suitable for the particle size determination of tadalafil drug substance. [ABSTRACT FROM AUTHOR]

In the paper K. L. Ngai et al., [J. Chem. 140, 044511 (2014)], the empirical correlation of ductility with the Poisson's ratio, υPoisson, found in metallic glasses was theoretically explained by microscopic dynamic processes which link on the one hand ductility, and on the other hand the Poisson's ratio. Specifically, the dynamic processes are the primitive relaxation in the Coupling Model which is the precursor of the Johari–Goldstein β-relaxation, and the caged atoms dynamics characterized by the effective Debye–Waller factor f0 or equivalently the nearly constant loss (NCL) in susceptibility. All these processes and the parameters characterizing them are accessible experimentally except f0 or the NCL of caged atoms; thus, so far, the experimental verification of the explanation of the correlation between ductility and Poisson's ratio is incomplete. In the experimental part of this paper, we report dynamic mechanical measurement of the NCL of the metallic glass La60Ni15Al25 as-cast, and the changes by annealing at temperature below Tg. The observed monotonic decrease of the NCL with aging time, reflecting the corresponding increase of f0, correlates with the decrease of υPoisson. This is important observation because such measurements, not made before, provide the missing link in confirming by experiment the explanation of the correlation of ductility with υPoisson. On aging the metallic glass, also observed in the isochronal loss spectra is the shift of the β-relaxation to higher temperatures and reduction of the relaxation strength. These concomitant changes of the β-relaxation and NCL are the root cause of embrittlement by aging the metallic glass. The NCL of caged atoms is terminated by the onset of the primitive relaxation in the Coupling Model, which is generally supported by experiments. From this relation, the monotonic decrease of the NCL with aging time is caused by the slowing down of the primitive relaxation and β-relaxation on annealing, and vice versa. [ABSTRACT FROM AUTHOR]

Ince-Gaussian (IG) beam with elliptical profile, as a connection between Hermite-Gaussian (HG) and Laguerre-Gaussian (LG) beams, has showed unique advantages in some applications such as quantum entanglement and optical micromanipulation. However, its dynamic generation with high switching frequency is still challenging. Here, we experimentally reported the quick generation of Ince-Gaussian beam by using a digital micro-mirror device (DMD), which has the highest switching frequency of 5.2 kHz in principle. The configurable properties of DMD allow us to observe the quasi-smooth variation from LG (with ellipticity ε= 0) to IG and HG (ε=∞) beam. This approach might pave a path to high-speed quantum communication in terms of IG beam. Additionally, the characterized axial plane intensity distribution exhibits a 3D mould potentially being employed for optical micromanipulation. [ABSTRACT FROM AUTHOR]

Electrochemical Strain Microscopy (ESM) can provide useful information on ionic diffusion in solids at the local scale. In this work, a finite element model of ESM measurements was developed and applied to commercial lithium manganese (III,IV) oxide (LiMn2O4) particles. ESM time spectroscopy was used, where a direct current (DC) voltage pulse locally disturbs the spatial distribution of mobile ions. After the pulse is off, the ions return to equilibrium at a rate which depends on the Li diffusivity in the material. At each stage, Li diffusivity is monitored by measuring the ESM response to a small alternative current (AC) voltage simultaneously applied to the tip. The model separates two different mechanisms, one linked to the response to DC bias and another one related to the AC excitation. It is argued that the second one is not diffusiondriven but is rather a contribution of the sum of several mechanisms with at least one depending on the lithium ion concentration explaining the relaxation process. With proper fitting of this decay, diffusion coefficients of lithium hosts could be extracted. Additionally, the effect of phase transition in LiMn2O4 is taken into account, explaining some experimental observations. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes (MWNT) were deposited via dropcasting and dried using vacuum filtration. Because of the slightly larger pore size (5–10 µm) of the paper substrate used as compared to the length of the nanotubes (0.5–2 µm), a variety of MWNT networks were formed both on the surface and through the thickness of the paper. Using a combination of impedance spectroscopy, equivalent circuit modeling, and microscopy techniques, it was possible to describe in detail how the electrical properties change as a function of how the MWNTs are distributed on the porous substrate by varying the number of deposited layers (1–20) as well as the dispersion concentration (0.1–5 mg/mL). In the in-plane, four different electrical responses were observed and modeled: (1) a substrate dominated spectrum representing unconnected MWNTs, (2) one that included bundle and junction responses as well as some inductances representing sparsely distributed MWNT networks, (3) followed by a parallel RL circuit for partially connected MWNT networks, and (4) finally a series RL circuit for fully connected MWNT networks. In the thru-plane, only two different electrical responses were observed and modeled. The results for the in-plane and thru-plane properties were used to generate percolation curves that show that electrical conductivity can change as much as 10 orders of magnitude for the same exact MWNTs. These results indicate that not only do the characteristics of the nanotubes themselves play a role but also the structure of the underlying substrate and the details of how the films are deposited. [ABSTRACT FROM AUTHOR]

The paper aimed to present the microscopic techniques used in botanical origin determination of honey samples, shortly melissopalynology. This technique is used for microscopic examination of pollen grains to determine the botanical origin of honey. It is known that a certain number of pollen grains must be recovered from sediment of honey solution, and the presence of small amounts of pollen may be related to falsification. Identification of pollen structure is generally made using light microscopy; phase contrast microscopy may be also used. Fluorescence microscopy is also a powerful method in palynology. Confocal laser scanning microscopy is effective in revealing the ultrastructure of pollen outer layer and shape of the pollen. The determination of the botanical origin of honey using palynology is based on the relative frequency of the pollen belonging to nectariferous plants. Honey is considered monofloral if the pollen from the sediment comes predominantly from a named botanical origin and overpasses 45% from the total count of pollen grains counted on the microscopic slide. [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Herein we present a study on the formation of irreversibly adsorbed layer of polystyrene molecules on silicon oxide surfaces. Various scanning probe microscopy techniques have been employed to study both the morphology and the mechanical properties of these self‐assembled thin polymeric layers. More in detail, standard contact mode, force versus distance spectroscopy and ultrasonic force microscopy have been employed to obtain spatially‐resolved maps and, thus, observe the physisorption of polystyrene on native silicon oxide substrate in function of time. Thick films, spin coated from a toluene solution, have been annealed at a temperature above the glass transition for increasing time intervals, and finally thoroughly rinsed in toluene. We have found that isolated islands of adsorbed chains are already present after an annealing time of half an hour. Prolonged annealing determines a progressive increase of the covered areas, whereas the formation of a complete flat layer requires 24 h. The pattern observed is in line with expected evolution of an unstable system, corresponding to the phenomenon of spinodal dewetting. Adhesion measurements show that the films present a reduced snap‐off and the formation of a meniscus between tip and surface for annealing time up to 8 h. On the other hand, elastic measurements allow us to observe a progressive increase of the elastic modulus, with a complete transition for annealing time above 20 h. This is indication that a dense packing of the polystyrene molecules occurs, in line with the predictions of current models on the kinetics of irreversible adsorption. Lay Description: Herein we present a study on the formation of irreversibly adsorbed layer of polystyrene molecules on silicon oxide surfaces. Various scanning probe microscopy techniques have been employed to study both the morphology and the mechanical properties of these self‐assembled thin polymeric layers. Thick polystyrene films, spin coated from a toluene solution, have been thermally annealed at a temperature above the glass transition for increasing time intervals, and finally thoroughly rinsed in toluene. We have found that isolated islands of adsorbed chains are already present after an annealing time of half an hour. Prolonged annealing determines a progressive increase of the covered areas, whereas the formation of a complete flat layer requires twenty‐four hours. The adsorption pattern observed is in line with expected evolution of an unstable system, corresponding to the phenomenon of spinodal dewetting. Adhesion and elastic measurements have allowed us to observe a progressive increase of the packing density of the polystyrene molecules, in agreement with the predictions of current models on the kinetics of irreversible adsorption. [ABSTRACT FROM AUTHOR]

Solvent effects are often difficult to understand in cases where reaction intermediates, and thus their differential behavior in different solvents, are not directly observable by traditional ensemble analytical techniques. Herein, the sensitivity of single‐particle fluorescence microscopy uniquely enables direct observation of organozinc intermediates and solvent effects on their build‐up and persistence. When combined with NMR spectroscopy, these imaging data pinpoint the previously elusive mechanistic origin of solvent effects in the synthesis of widely used organozinc reagents. These findings characterize the acceleration of oxidative addition of the starting organoiodide to the surface of zinc metal in DMSO relative to THF, but once formed, surface intermediates display similar persistence in either solvent. The current studies are the first demonstration of a highly sensitive, single‐particle fluorescence microscopy technique to pinpoint otherwise elusive solvent effects in synthetic chemistry. [ABSTRACT FROM AUTHOR]

Ancient latrine sediments, which contain the concentrated collective biological waste of past whole human communities, have the potential to be excellent proxies for human gastrointestinal health on the population level. A rich body of literature explores their use to detect the presence of gut-associated eukaryotic parasites through microscopy, immunoassays and genetics. Despite this interest, a lack of studies have explored the whole genetic content of ancient latrine sediments through consideration not only of gut-associated parasites, but also of core community gut microbiome signals that remain from the group that used the latrine. Here, we present a metagenomic analysis of bulk sediment from medieval latrines in Riga (Latvia) and Jerusalem. Our analyses reveal survival of microbial DNA representative of intestinal flora as well as numerous parasites. These data are compared against parasite taxon identifications obtained via microscopy and ELISA techniques. Together, these findings provide a first glimpse into the rich prokaryotic and eukaryotic intestinal flora of pre-industrial agricultural populations, which may give a better context for interpreting the health of modern microbiomes. [ABSTRACT FROM AUTHOR]

In recent years, fluorescence microscopy techniques for the localization and tracking of single molecules in living cells have become well-established and are indispensable tools for the investigation of cellular biology and in vivo biochemistry of many bacterial and eukaryotic organisms. Nevertheless, these techniques are still not established for imaging archaea. Their establishment as a standard tool for the study of archaea will be a decisive milestone for the exploration of this branch of life and its unique biology. Here, we have developed a reliable protocol for the study of the archaeon Haloferax volcanii. We have generated an autofluorescence-free H. volcanii strain, evaluated several fluorescent proteins for their suitability to serve as single-molecule fluorescence markers and codon-optimized them to work under optimal H. volcanii cultivation conditions. We found that two of them, Dendra2Hfx and PAmCherry1Hfx, provide state-of-the-art single-molecule imaging. Our strategy is quantitative and allows dual-color imaging of two targets in the same field of view (FOV) as well as DNA co-staining. We present the first single-molecule localization microscopy (SMLM) images of the subcellular organization and dynamics of two crucial intracellular proteins in living H. volcanii cells, FtsZ1, which shows complex structures in the cell division ring, and RNA polymerase, which localizes around the periphery of the cellular DNA. This work should provide incentive to develop SMLM strategies for other archaeal organisms in the near future. [ABSTRACT FROM AUTHOR]

To be able to resolve molecular-clusters it is crucial to access vital information (such as, molecule density, cluster-size, and others) that are key in understanding disease progression and the underlying mechanism. Traditional single-molecule localization microscopy (SMLM) techniques use molecules of variable sizes (as determined by its localization precision (LP)) to reconstruct a super-resolution map. This results in an image with overlapping and superimposing PSFs (due to a wide size-spectrum of single-molecules) that undermine image resolution. Ideally, it should be possible to identify the brightest molecules (also termed as the fortunate molecules) to reconstruct ultra-superresolution map, provided sufficient statistics is available from the recorded data. Probabilistic Optically-Selective Single-molecule Imaging Based Localization Encoded (POSSIBLE) microscopy explores this possibility by introducing a narrow probability size-distribution of single-molecules (narrow size-spectrum about a predefined mean-size). The reconstruction begins by presetting the mean and variance of the narrow distribution function (Gaussian function). Subsequently, the dataset is processed and single-molecules are filtered by the Gaussian function to remove unfortunate molecules. The fortunate molecules thus retained are then mapped to reconstruct an ultra-superresolution map. In-principle, the POSSIBLE microscopy technique is capable of infinite resolution (resolution of the order of actual single-molecule size) provided enough fortunate molecules are experimentally detected. In short, bright molecules (with large emissivity) holds the key. Here, we demonstrate the POSSIBLE microscopy technique and reconstruct single-molecule images with an average PSF sizes of σ ± Δσ = 15 ± 10 nm, 30 ± 2 nm & 50 ± 2 nm. Results show better-resolved Dendra2-HA clusters with large cluster-density in transfected NIH3T3 fibroblast cells as compared to the traditional SMLM techniques. Cluster analysis indicates densely-packed HA molecules, HA-HA interaction, and a surge in the number of HA molecules per cluster post 24 Hrs of transfection. The study using POSSIBLE microscopy introduces new insights in influenza biology. We anticipate exciting applications in the multidisciplinary field of disease biology, oncology, and biomedical imaging. [ABSTRACT FROM AUTHOR]

Controlled and straightforward functionalization are relevant strategies to obtain MoS2 platforms with defined functionality and improved processability. In this work, an efficient strategy for the functionalization of MoS2 using Reversible Addition Fragmentation Transfer (RAFT) polymerization is reported. The RAFT reagent was directly created on the surface of freshly exfoliated MoS2 and the obtained two-dimensional platform was used for the polymerization of styrene and acrylamide monomers. Various ratios of divinylbenzene were used to crosslink polystyrene brushes and create a polymeric coverage on the surface of MoS2. Furthermore, the polymerization of a mixture of styrene and acrylamide monomers using a MoS2-based RAFT agent resulted in two-dimensional platforms containing copolymer brushes. The structures of the synthesized two-dimensional materials were investigated using different spectroscopy and microscopy techniques as well as thermal and elemental analyses. This research provides an efficient method for the preparation of functional two-dimensional MoS2 nanostructures using RAFT polymerization in gram scale. [ABSTRACT FROM AUTHOR]

Post mortem magnetic resonance imaging (MRI) studies on the human brain are of great interest for the validation of in vivo MRI. It facilitates a link between functional and anatomical information available from MRI in vivo and neuroanatomical knowledge available from histology/immunocytochemistry. However, linking in vivo and post mortem MRI to microscopy techniques poses substantial challenges. Fixation artifacts and tissue deformation of extracted brains, as well as co registration of 2D histology to 3D MRI volumes complicate direct comparison between modalities. Moreover, post mortem brain tissue does not have the same physical properties as in vivo tissue, and therefore MRI approaches need to be adjusted accordingly. Here, we present a pipeline in which whole-brain human post mortem in situ MRI is combined with subsequent tissue processing of the whole human brain, providing a 3-dimensional reconstruction via blockface imaging. To this end, we adapted tissue processing procedures to allow both post mortem MRI and subsequent histological and immunocytochemical processing. For MRI, tissue was packed in a susceptibility matched solution, tailored to fit the dimensions of the MRI coil. Additionally, MRI sequence parameters were adjusted to accommodate T1 and T2∗ shortening, and scan time was extended, thereby benefiting the signal-to-noise-ratio that can be achieved using extensive averaging without motion artifacts. After MRI, the brain was extracted from the skull and subsequently cut while performing optimized blockface imaging, thereby allowing three-dimensional reconstructions. Tissues were processed for Nissl and silver staining, and co-registered with the blockface images. The combination of these techniques allows direct comparisons across modalities. [ABSTRACT FROM AUTHOR]

Copyright of Anatolian Bryology is the property of Cankri Karatekin University, Orman Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Ivermectin is an excellent microfilaricide against Onchocerca volvulus. However, in some regions, long term use of ivermectin has resulted in sub-optimal responses to the treatment. More data to properly document the phenomenon in various contexts of ivermectin mass drug administration (IVM-MDA) is needed. Also, there is a need to accurately monitor a possible repopulation of skin by microfilariae following treatment. Skin snip microscopy is known to have a low sensitivity in individuals with light infections, which can be the case following treatment. This study was designed with two complementary objectives: (i) to assess the susceptibility of O. volvulus microfilariae to ivermectin in two areas undergoing IVM-MDA for different lengths of time, and (ii) to document the repopulation of skin by the O. volvulus microfilariae following treatment, using 3 independent diagnostic techniques.Method: Identified microfilaridermic individuals were treated with ivermectin and re-examined after 1, 3, and 6 months using microscopy, actin real-time PCR (actin-qPCR) and O-150 LAMP assays. Susceptibility to ivermectin and trends in detecting reappearance of skin microfilariae were determined using three techniques. Microscopy was used as an imperfect gold standard to determine the performance of actin-qPCR and LAMP.Results: In Bafia with over 20 years of IVM-MDA, 11/51 (21.6%) direct observe treated microfilaridemic participants were still positive for skin microfilariae after 1 month. In Melong, with 10 years of IVM-MDA, 2/29 (6.9%) treated participants were still positive. The microfilarial density reduction per skin biopsy within one month following treatment was significantly lower in participants from Bafia. In both study sites, the molecular techniques detected higher proportions of infected individuals than microscopy at all monitoring time points. LAMP demonstrated the highest levels of sensitivity and real-time PCR was found to have the highest specificity.Conclusion: Patterns in skin mirofilariae clearance and repopulation were established. O. volvulus worms from Bafia with higher number of annual MDA displayed a lower clearance and higher repopulation rate after treatment with ivermectin. Molecular assays displayed higher sensitivity in monitoring O. volvulus microfilaridemia within six months following treatment. [ABSTRACT FROM AUTHOR]

The advent of high-flux, high-brilliance synchrotron radiation (SR) has prompted the development of high-resolution X-ray imaging techniques such as full-field microscopy, holography, coherent diffraction imaging and ptychography. These techniques have strong potential to establish non-destructive three- and four-dimensional nano-imaging when combined with computed tomography (CT), called nano-tomography (nano-CT). X-ray nano-CTs based on full-field microscopy are now routinely available and widely used. Here we discuss the current status and some applications of nano-CT using a Fresnel zone plate as an objective. Optical properties of full-field microscopy, such as spatial resolution and off-axis aberration, which determine the effective field of view, are also discussed, especially in relation to 3D tomographic imaging. [ABSTRACT FROM AUTHOR]

About half the wood extracted worldwide from forests is used as fuelwood to produce energy, about 17 percent is converted to charcoal (FAO 2017) which represents one of the least controlled/monitored segments of the European timber market. Although charcoal has a significant share on the European market of wood-based products it is not yet covered by the European Timber Regulations (EUTR), (EU) No 995/2010. For this project, a total of 150 charcoal consignments from eleven countries (Germany, Poland, Switzerland, Spain, Italy, Norway, Denmark, Netherlands, Ukraine, Czech Republic, and Belgium) were examined and evaluated based on the 3D-reflected light microscopy technique. The high-resolution study indicates the proportion of different European timbers compared with that of timbers from subtropical and tropical regions. The share of subtropical and tropical species is surprisingly high with approximately 46% for material received from all countries studied, but far over 60% for Spain, Italy, Poland, and Belgium. The study shows that comparing the results for charcoal received from these countries there is an inversely proportional relation of certified products (FSC and PEFC) and products with timbers from subtropical or tropical origins. In the charcoal consignments from Switzerland, the share of timbers from subtropical or tropical origin is only 13.5%, whereas that of certified products is 60%. In material received from Spain, the proportion of timbers from subtropical or tropical regions is 67%, whereas that of certified products only 8%. A careful check of the declaration on the packaging, of the accompanying certificates, and the information on origin revealed alarming evidence: only 25% of the consignments examined provide information on the bags, e.g., with regard to the processed wood species; and well over half of such declarations were incorrect and/or incomplete. A trade flow analysis of EU member states was carried out to contribute to a better understanding of the relationships between international charcoal trade flows and the end products in European countries. This approach contributes to an essential understanding of charcoal transit in Europe and the results constitute a strong motive for the inclusion of charcoal in the respective annex to the EUTR. [ABSTRACT FROM AUTHOR]

Perovskite semiconductors are an exciting class of materials due to their promising performance outputs in photovoltaic devices. To boost their efficiency further, researchers introduce additives during sample synthesis, such as KI. However, it is not well understood how KI changes the material and, often, leaves precipitants. To fully resolve the role of KI, multiple microscopy techniques are applied and the electrical and chemical behavior of a Reference (untreated) and a KI‐treated perovskite are compared. Upon correlation between electrical and chemical nanoimaging techniques, it is discovered that these local properties are linked to the macroscopic voltage enhancement of the KI‐treated perovskite. The heterogeneity revealed in both the local electrical and chemical responses indicates that the additive partially migrates to the surface, yet surprisingly does not deteriorate the performance locally, rather, the voltage response homogeneously increases. The research presented within provides a diagnostic methodology, which connects the nanoscale electrical and chemical properties of materials, relevant to other perovskites, including multication and Pb‐free alternatives. [ABSTRACT FROM AUTHOR]

Although research and new technologies have introduced different ways of observing microorganisms, including scanning and electron microscopy, these methods are expensive and require equipment that is typically not found in a middle school classroom. The transmission-through-dye technique (TTD; Gregg et al., 2010), a new optical microscopy method that can be used with current basic light microscopes, relies on the fairly simple mechanism of filtered light passing through a dyed medium to produce an image that reflects cell thickness. With this technique, living microorganisms look bright red against a dark background, and movement can be seen easily among dead microorganisms and debris that show up black. Since the technique is low-cost and easy to implement, it addresses the needs of practitioners and is appropriate for a wide array of school contexts. We describe a three-week, hands-on, inquiry-based unit on TTD microscopy for middle and high school students. [ABSTRACT FROM AUTHOR]

Premise of research. The morphology of leaves is shaped by both historical and current selection acting on constrained developmental systems. For this reason, the phylogenetic signal of these characters is usually overlooked. Methodology. We investigate morphology of the leaflets of all genera of the Zamiaceae using multiple microscopical techniques to test whether leaf characters present a phylogenetic signal and whether they are useful to define clades at a suprageneric level. Pivotal results. Our investigation shows that most genera are quite uniform in their leaflet anatomy, with the largest genera (Zamia , Encephalartos) presenting the highest degree of variation. Using both Bayesian and parsimony methods on two different molecular scaffolds, we are able to show that leaflet anatomy has a strong phylogenetic signal in the Zamiaceae and that many clades retrieved by molecular analyses present potential synapomorphies in their leaflet anatomy. Particularly, the placement of Stangeria in a clade with Zamia and Microcycas is supported by the presence of both an adaxial and an abaxial girder sclerenchyma and the absence of sclerified hypodermis. The placement of Stangeria as sister to Bowenia , on the other hand, is not supported by our analysis. Instead, our results put into question the homology of the similar guard cell morphology in the two genera. Conclusions. We show that leaflet anatomy has a substantial amount of phylogenetic signal in the Zamiaceae, supporting relationships that are not supported by general morphology. Therefore, anatomical investigation represents a promising avenue for plant systematists. [ABSTRACT FROM AUTHOR]

The development of materials is strongly related to our capability of understanding thermal, mechanical and chemical processing on the nanoscale. Unravelling the interface structure is crucial for opening new regimes in property–performance space. Interface arrangements have been characterized by statistically limited microscopy techniques. In this work, a large‐angular‐range detector was used for synchrotron diffraction measurements on commercially pure Mg. Long acquisitions allowed the retrieval of preferred interface configurations through the observation of extraordinary diffraction peaks located close to the Mg 102, 200, 204 and 300 fundamental reflections. A kinematical simulation scanning possible interface structures established the correspondence of the non‐bulk peaks to the interfacial organization of atoms that may be responsible for their appearance. Simulated interfaces were probed for a wide range of angular displacements with respect to the main cleavage planes. The results indicate configurations that allow the observation of X‐ray diffraction, representing a long‐range‐ordered pattern of atomic distributions in Mg. The introduced methodology allows for nondestructive monitoring of systems that undergo processes that modify grain sizes and grain‐interface orientation. [ABSTRACT FROM AUTHOR]

Three-dimensional (3-D) light solitons in space–time, referred to as light bullets, have many novel properties and wide applications. Here we theoretically show how the combination of diffraction-free beam and ultrashort pulse spatiotemporal-coupling enables the creation of a straight-line propagation light bullet with freely tunable velocity and acceleration. This light bullet could propagate with a constant superluminal or subluminal velocity, and it could also counter-propagate with a very fast superluminal velocity (e.g., − 35.6c). Apart from uniform motion, an acceleration or deceleration straight-line propagation light bullet with a tunable instantaneous acceleration could also be produced. The high controllability of the velocity and the acceleration of a straight-line propagation light bullet would enable very specific applications, such as velocity and/or acceleration matched micromanipulation, microscopy, particle acceleration, radiation generation, and so on. [ABSTRACT FROM AUTHOR]

In this study, we have analyzed the formation mechanisms and processing-microstructure relationships for Al/TiC metal matrix nanocomposites produced in situ via thermite-assisted (e.g., CuO) self-propagating high-temperature synthesis (SHS). Al/TiC composites were created by reacting Al-Ti-C-CuO pellets in an Al melt using a wide variety of processing conditions (e.g., precursor powder amounts, bulk melt temperature, precursor powder size, pellet packing method). As-cast composites were visualized using both 2D (SEM) and 3D (TXM) microscopy techniques, to study TiC particle and secondary precipitate (e.g., Al3Ti) characteristics at the nanoscale. SHS-produced samples reveal complex microstructures consisting of individual and clustered TiC particles, elongated Al3Ti intermetallics, and C-rich regions surrounded by TiC. Based on a thermodynamic analysis and our microstructural observations, we propose three dominant TiC formation pathways, each resulting in a distinct microstructural signature. Finally, we utilize multivariate statistics (canonical correlations) on the full breadth of imaging data to infer the dominant processing variables (i.e., amount of CuO and C) that most strongly influence TiC particle characteristics and the final composite microstructure. We also discuss how the dominant processing variables relate to the proposed formation pathways and how they may inform the rational design of future composites produced via thermite-assisted SHS. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Científico Centro de Museos de Historia Natural is the property of Universidad de Caldas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: By being at the interface of the exocytic and endocytic pathways, the plant trans‐Golgi network (TGN) is a multitasking and highly diversified organelle. Despite governing vital cellular processes, the TGN remains one of the most uncharacterized organelle of plant cells. In this review, we highlight recent studies that have contributed new insights and to the generation of markers needed to answer several important questions on the plant TGN. Several drugs specifically affecting proteins critical for the TGN functions have been extremely useful for the identification of mutants of the TGN in the pursuit to understand how the morphology and the function of this organelle are controlled. In addition to these chemical tools, we review emerging microscopy techniques that help visualize the TGN at an unpreceded resolution and appreciate the heterogeneity and dynamics of this organelle in plant cells. [ABSTRACT FROM AUTHOR]

We describe the histological appearance of the osteoderms (ODs) of Heloderma suspectum and Varanus komodoensis using multiple staining and microscopy techniques to yield information about their morphology and development. Histological analysis showed that the ODs of H. suspectum are composed of three main tissue types, a superficial layer, herein identified as osteodermine, capping a base composed of Sharpey‐fibre bone and lamellar bone rich in secondary osteons (Haversian bone tissue). In contrast, ODs in V. komodoensis are composed of a core of woven bone surrounded by parallel‐fibred bone without a capping tissue. Thus, in these two species, ODs differ both in terms of their structural composition and in details of their skeletogenesis. The histology of the mineralised tissues observed in these two reptile taxa provides insights into the mechanism of formation of lizard ODs and presents a direct comparison of the histological properties between the ODs of the two species. These data allow greater understanding of the comparative histological appearance of the dermal bones of lizards and highlight their structural diversity. [ABSTRACT FROM AUTHOR]

Developmental biology relies heavily on our ability to generate three-dimensional images of live biological specimens through time, and to map gene expression and hormone response in these specimens as they undergo development. The last two decades have seen an explosion of new bioimaging technologies that have pushed the limits of spatial and temporal resolution and provided biologists with invaluable new tools. However, plant tissues are difficult to image, and no single technology fits all purposes; choosing between many bioimaging techniques is not trivial. Here, we review modern light microscopy and computed projection tomography methods, their capabilities and limitations, and we discuss their current and potential applications to the study of flower development and fertilization. [ABSTRACT FROM AUTHOR]

The Goos–Hänchen effect has found many important applications in photonics and optoelectronics since its discovery in 1947. Here, we propose unique applications of the Goos–Hänchen effect in optical differential operation and image edge detection. This Letter describes the theoretical foundation and experimental realization of the proposed scheme. By incorporating with the microscopy technique, our scheme may find important applications in cell and molecular imaging. [ABSTRACT FROM AUTHOR]

In recent years, there have been numerous efforts worldwide to develop the synchrotron X‐ray scanning tunneling microscopy (SX‐STM) technique. Here, the inauguration of XTIP, the world's first beamline fully dedicated to SX‐STM, is reported. The XTIP beamline is located at Sector 4 of the Advanced Photon Source at Argonne National Laboratory. It features an insertion device that can provide left‐ or right‐circular as well as horizontal‐ and vertical‐linear polarization. XTIP delivers monochromatic soft X‐rays of between 400 and 1900 eV focused into an environmental enclosure that houses the endstation instrument. This article discusses the beamline system design and its performance. [ABSTRACT FROM AUTHOR]

The development of materials science always benefits from advanced characterizations. Currently, imaging techniques are of great technological importance in both fundamental and applied research on materials. In comparison to conventional visualization methods, confocal laser scanning microscopy (CLSM) is non-invasive, with macroscale and high-contrast scanning, a simple and fast sample preparation procedure as well as easy operation. In addition, CLSM allows rapid acquisition of longitudinal and cross-sectional images at any position in a material. Therefore, the CLSM-based visualization technique could provide direct and model-independent insight into material characterizations. This review summarizes the recent applications of CLSM in materials science. The current CLSM approaches for the visualization of surface structures, internal structures, spatial structures and reaction processes are discussed in detail. Finally, we provide our thoughts and predictions on the future development of CLSM in materials science. The purpose of this review is to guide researchers to build a suitable CLSM approach for material characterizations, and to open viable opportunities and inspirations for the development of new strategies aiming at the preparation of advanced materials. We hope that this review will be useful for a wide range of research communities of materials science, chemistry, and engineering. [ABSTRACT FROM AUTHOR]