Search

Background/Objectives: Mummy studies allow to reconstruct the characteristic of a population in a specific spatiotemporal context, in terms of living conditions, pathologies and death. Radiology represents an efficient diagnostic technique able to establish the preservation state of mummified organs and to estimate the patient's pathological conditions. However, the radiological approach shows some limitations. Although bone structures are easy to differentiate, soft tissue components are much more challenging, especially when they overlap. For this reason, computed tomography, a well-established approach that achieves optimal image contrast and three-dimensional reconstruction, has been introduced. This original article focuses attention on the role of virtual dissection as a promising technology for exploring human mummy anatomy and considers the potential of environmental scanning electron microscopy and X-ray spectroscopy as complementary approaches useful to understand the state of preservation of mummified remains. Methods: Ancient mummy corps have been analyzed through Anatomage Table 10 and environmental scanning electron microscope equipped with X-ray spectrometer; Results: Anatomage Table 10 through various volumetric renderings allows us to describe spine alteration due to osteoarthritis, dental state, and other clinical-pathological characteristics of different mummies. Environmental scanning electron microscope, with the advantage of observing mummified samples without prior specimen preparation, details on the state of tissue fragments. Skin, tendon and muscle show a preserved morphology and keratinocytes, collagen fibers and tendon structures are easily recognizable. Furthermore, X-ray spectrometer reveals in our tissue remains, the presence of compounds related to soil contamination. This investigation identifies a plethora of organic and inorganic substances where the mummies were found, providing crucial information about the mummification environment. Conclusions: These morphological and analytical techniques make it possible to study mummified bodies and describe their anatomical details in real size, in a non-invasive and innovative way, demonstrating that these interdisciplinary approaches could have great potential for improving knowledge in the study of ancient corpses. [ABSTRACT FROM AUTHOR]

The formulation of paediatric medicines faces significant challenges to meet the requirements for safe and accurate administration, while maintaining a suitable taste. Multiparticulate formulations have a strong potential to address these challenges because they combine dose flexibility with ease of administration. Understanding the stability of multiparticulate formulations over storage as a function of time and environmental parameters, such as humidity and temperature, is important to manage their commercialisation and use. In this work, we have expanded the toolkit of available techniques for studying multiparticulates beyond those such as scanning electron microscopy (SEM) and confocal laser scanning microscopy. We include advanced methods of environmentally-controlled SEM to monitor temperature- and humidity-induced changes in-situ , and a variety of Raman spectroscopies including stimulated Raman scattering microscopy to identify and localise the different ingredients at the surface and inside the multiparticulates. These techniques allowed unprecedented monitoring of specific changes to the particulate structure and distribution of individual ingredients due to product aging. These methods should be considered as valuable novel tools for in-depth characterisation of multiparticulate formulations to further understand chemical changes occurring during their development, manufacturing and long-term storage. We envisage these techniques to be useful in furthering the development of future medicine formulations. [Display omitted] • Raman spectroscopy mapping of the surface of multiparticulates, with corresponding scanning electron microscopy (SEM) imaging to combine chemical and physical information. • Accelerated aging studies within environmental SEM (ESEM), combined with Raman spectroscopy point measurements to identify chemical and structural changes. • Stimulated Raman scattering (SRS) microscopy imaging to rapidly identify the location of the API and excipients across large particle populations. • Insights into the behaviour of poloxamer 407 and glyceryl dibehenate in multiparticulates when exposed to different environmental conditions. [ABSTRACT FROM AUTHOR]

Metal sub-microparticles (SMPs) and nanoparticles (NPs) presence in food is attributable to increasing pollution from the environment in raw materials and finished products. In the present study, a multifaceted analytical strategy based on Environmental Scanning Electron Microscopy and High-Angle Annular Dark-Field—Scanning Transmission Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy (ESEM-EDX, HAADF-STEM-EDX) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was proposed for the detection and characterization of metal and metal-containing SMPs and NPs in durum wheat samples, covering a size measurement range from 1 nm to multiple µm. ESEM-EDX and ICP-MS techniques were applied for the assessment of SMP and NP contamination on the surface of wheat grains collected from seven geographical areas characterized by different natural and anthropic conditions, namely Italy, the USA, Australia, Slovakia, Mexico, Austria, and Russia. ICP-MS showed significant differences among the mean concentration levels of metals, with the USA and Italy having the highest level. ESEM-EDX analysis confirmed ICP-MS concentration measurements and measured the highest presence of particles < 0.8 µm in size in samples from Italy, followed by the USA. Less marked differences were observed when particles < 0.15 µm were considered. HAADF-STEM-EDX was applied to a selected number of samples for a preliminary assessment of internal contamination by metal SMPs and NPs, and to expand the measurable particle size range. The multifaceted approach provided similar results for Fe-containing SMPs and NPs. ICP-MS and ESEM-EDX also highlighted the presence of a significant abundance of Ti- and Al-containing particles, while for STEM-EDX, sample preparation artifacts complicated the interpretation. Finally, HAADF-STEM-EDX results provided relevant information about particles in the low nm range, since, by applying this technique, no particles smaller than 50 nm were observed in accordance with ESEM-EDX. [ABSTRACT FROM AUTHOR]

Background/Objectives: Mummy studies allow to reconstruct the characteristic of a population in a specific spatiotemporal context, in terms of living conditions, pathologies and death. Radiology represents an efficient diagnostic technique able to establish the preservation state of mummified organs and to estimate the patient's pathological conditions. However, the radiological approach shows some limitations. Although bone structures are easy to differentiate, soft tissue components are much more challenging, especially when they overlap. For this reason, computed tomography, a well-established approach that achieves optimal image contrast and three-dimensional reconstruction, has been introduced. This original article focuses attention on the role of virtual dissection as a promising technology for exploring human mummy anatomy and considers the potential of environmental scanning electron microscopy and X-ray spectroscopy as complementary approaches useful to understand the state of preservation of mummified remains. Methods: Ancient mummy corps have been analyzed through Anatomage Table 10 and environmental scanning electron microscope equipped with X-ray spectrometer; Results: Anatomage Table 10 through various volumetric renderings allows us to describe spine alteration due to osteoarthritis, dental state, and other clinical-pathological characteristics of different mummies. Environmental scanning electron microscope, with the advantage of observing mummified samples without prior specimen preparation, details on the state of tissue fragments. Skin, tendon and muscle show a preserved morphology and keratinocytes, collagen fibers and tendon structures are easily recognizable. Furthermore, X-ray spectrometer reveals in our tissue remains, the presence of compounds related to soil contamination. This investigation identifies a plethora of organic and inorganic substances where the mummies were found, providing crucial information about the mummification environment. Conclusions: These morphological and analytical techniques make it possible to study mummified bodies and describe their anatomical details in real size, in a non-invasive and innovative way, demonstrating that these interdisciplinary approaches could have great potential for improving knowledge in the study of ancient corpses.

In contrast to the freeze-drying process, the rehydration process of freeze-dried foods remains unclear. This study investigated the rehydration of freeze-dried soybean curd, also known as tofu, and elucidated its breakage mechanism during rehydration, which impairs texture. The rehydration of freeze-dried tofu was observed at different water temperatures (20, 40, 70, and 100 °C), with the required rehydration time found to decrease with increasing water temperature. Furthermore, tofu was found to absorb water faster in cracks formed during production than in the porous body. Crack expansion was observed only in hightemperature water, leading to breakage of the tofu. Environmental scanning electron microscopy revealed that tofu expanded when a sufficient amount of water was absorbed. Accordingly, crack expansion in hightemperature water is attributed to the stress concentration at the tip of the crack, which is caused by differences in the rehydration rate and resulting stiffness between the porous body and cracks. [ABSTRACT FROM AUTHOR]

Microplasmas can be used for a wide range of technological applications and to improve the understanding of fundamental physics. Scanning electron microscopy, on the other hand, provides insights into the sample morphology and chemistry of materials from the mm‐ down to the nm‐scale. Combining both would provide direct insight into plasma‐sample interactions in real‐time and at high spatial resolution. Up till now, very few attempts in this direction have been made, and significant challenges remain. This work presents a stable direct current glow discharge microplasma setup built inside a scanning electron microscope. The experimental setup is capable of real‐time in situ imaging of the sample evolution during plasma operation and it demonstrates localized sputtering and sample oxidation. Further, the experimental parameters such as varying gas mixtures, electrode polarity, and field strength are explored and experimental V–I curves under various conditions are provided. These results demonstrate the capabilities of this setup in potential investigations of plasma physics, plasma‐surface interactions, and materials science and its practical applications. The presented setup shows the potential to have several technological applications, for example, to locally modify the sample surface (e.g., local oxidation and ion implantation for nanotechnology applications) on the µm‐scale. [ABSTRACT FROM AUTHOR]

Objective: To effectively solve the difficulty of observing the electron microstructure of samples with high water content. Methods: A series of samples with high water content were observed by conventional scanning electron microscope with a new mode instrument combination of semiconductor cold cooling table. Results: Under the conditions of conductive tape as matrix, voltage 5 kV, electron beam spot of 50 or 60, and cold table temperature of 4 ℃, the sample with high water content did not need to be fixed and dehydrated, and its microstructure could be directly imaged under the scanning electron microscope to observe its microstructure. The microstructure of the sample hadd no deformation phenomena such as shrinkage, stretching and distortion, which could reflect the original appearance of the sample more realistically. Conclusion: The new mode of free combination of conventional scanning electron microscope with semiconductor cold cooling table is an effective means to solve the microstructure observation of high water content samples, and is an economical, cost-effective and widely adaptable mode.

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office 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.)

Most methodologies to measure the moisture‐induced deformation (hygro‐expansion) of paper microconstituents, including fibres and interfibre bonds, are low resolution or time‐consuming. Hence, here, a novel method is proposed and validated to measure high‐resolution full‐field strain maps of paper microconstituents during hygro‐expansion, based on environmental scanning electron microscopy (ESEM). To this end, a novel climate stage enables accurate control of the relative humidity (RH) near the specimen in the ESEM from 0%–100%. The fibre surface, which is decorated a priori with a microparticle pattern, is captured during RH change. Subsequently, correlating the fibre surface using a dedicated global digital image correlation algorithm enables high‐resolution hygro‐expansion strain maps. Method optimisation involved performing contrast enhancement, scan‐correction to reduce ESEM artefacts and a background correction, resulting in a strain resolution of 6·10−4. Method validation revealed that the fibres' crystallinity is affected by the electron beam, even for minimal invasive electron beam settings. Interestingly, however, the fibres consistently exhibit conventional hygro‐expansion behaviour during the drying slopes. Using the optimised procedure, hygro‐expansion characterisation of two interfibre bonds and four interfibre bond cross‐sections revealed the competition between the low longitudinal and large transverse fibre hygro‐expansion in the bonded area. [ABSTRACT FROM AUTHOR]

Soil aggregates are a crucial constituent of soil and have a significant function in regulating water, nutrients, air, and heat within the soil. The development of soil aggregates is influenced by various factors, including the soil’s parent material and human activities. Understanding the formation and the mechanism of stabilization of soil aggregates is of great significance in the study of soil development, in regulating and managing organic carbon pools in soils, and in promoting soil fertility. In this study, aeolian sandy soil with a low degree of soil development and compound soil formed by combining soft rock and aeolian sandy soil were selected as the research objects. We selected three time points from 0 to 9 years after amendment by soft rock in order to investigate the changes of soil aggregate cementing agents. The shape of soil aggregates in both types of soils was analyzed by environmental scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), which were also used to assess the appearance of soil aggregates and quantify the composition of mineral elements on a cross section of the aggregate. The results show that when the soft rock and the aeolian sandy soil are compounded and mixed, the clay minerals in the soft rock change the microstructure of the original aeolian sandy soil from a single granular barrier to one characterized by a cumulative porous structure, indicating that clay minerals promote soil development and form aggregates with good structural properties. The cementing agents in the compounded soil aggregates are mainly clay minerals, aluminum, iron, and calcium. In comparison to aeolian sandy soils, the presence of iron and calcium in compounded soils is notably elevated. The iron oxides present in compounded soils serve a similar function to “bolts” in the formation of soil aggregates. These findings establish a theoretical foundation for investigating the process of soil aggregate formation and the mechanisms by which cementing agents contribute to their stabilization.

Two nanomicas of similar composition, containing muscovite and quartz, but with different particle size distributions, have been used to prepare transparent epoxy nanocomposites. Their homogeneous dispersion, due to the nano-size, was achieved even without being organically modified, and no aggregation of the nanoparticles was observed, thus maximizing the specific interface between matrix and nanofiller. No exfoliation or intercalation has been observed by XRD, despite the significant dispersion of the filler in the matrix which produced nanocomposites with a loss in transparency in the visible domain of less than 10% in the presence of 1% wt and 3% wt of mica fillers. The presence of micas does not affect the thermal behavior of the nanocomposites, which remains similar to that of the neat epoxy resin. The mechanical characterization of the epoxy resin composites revealed an increased Young's modulus, whereas tensile strength was reduced. A peridynamics-based representative volume element approach has been implemented to estimate the effective Young's modulus of the nanomodified materials. The results obtained through this homogenization procedure have been used as input for the analysis of the nanocomposite fracture toughness, which has been carried out by a classical continuum mechanics–peridynamics coupling approach. Comparison with the experimental data confirms the capability of the peridynamics-based strategies to properly model the effective Young's modulus and fracture toughness of epoxy-resin nanocomposites. Finally, the new mica-based composites exhibit high values of volume resistivity, thus being excellent candidates as insulating materials. [ABSTRACT FROM AUTHOR]

Hydrophobic materials in geotechnical engineering and soil science can have natural or artificial origin. They can be applied, e. g., to waterproof structures in the industry. In this contribution, hydrophobic granular material was manufactured through a cold plasma polymer coating procedure. The monomer used was C4F8 (octafluorocyclobutane) and the material to be coated was Hamburg sand, a coarse grained sand. In this context, computed microtomography and environmental scanning electron microscopy were used to investigate the materials in their unsaturated state. The tools are applied to visualize unsaturated phenomena on the microscale. The hydrophobic and untreated materials were imaged by both techniques at different saturation degrees in order to understand the influence of the coating on the sample’s hydraulic behaviour. The chosen environmental scanning electron microscope is able to provide relative humidity in the sample chamber, and so water drops were condensed on the grain surface, allowing to also observe the initial contact of water and the hydrophobic coating. It was observed how the capillary menisci, their geometry and contact properties evolve at different degrees of saturation. The measurements obtained and respective analyses state qualitatively the influence of the hydrophobic coatings on the pore water dynamics at different saturation degrees, which dictates the material’s hydraulic behaviour. Contact angles were also analysed were it was physically possible.

Xylem vessels are essential pivotal organs in bulk hydraulic flow through the whole woody plant. However, environmental constraints generate disagreements in xylem structures, which are characterized by air emboli and occlusions formations, compromising water conductivity in grapevines. The aim of this work was to explore xylem morphology dynamics through the xylem sap flow of five Tunisian grapevine cultivars during the natural bleeding sap periods of 2019, 2021, and 2022. In fact, Sakasly, Khamri, Hencha, Razegui1, and Razegui2 rain-fed grapevine cultivars revealed differential responses towards xylem sap movement. The results demonstrated that the xylem sap flow was significantly more abundant in 2019 than 2021 and 2022 bleeding sap campaigns. A variation was revealed between the cultivars regarding the xylem sap flow. In fact, Sakasly gave the best xylem flow during the three campaigns. Razegui1 and Razegui2 registered approximately similar xylem sap flow, while Hencha and Khamri present the lowest sap fluxes during the three campaigns. Moreover, several vascular occlusions forms were identified from stem cross sections using environmental scanning electron microscopy (ESEM), including tyloses, gels, starch, and gum deposits. The highest occlusion number was observed in Sakasly, Razegui1, and Razegui2 cultivars. Among different biogenic calcium shapes, several were observed for the first time in grapevine, including multi-faceted druse, cubic, crystalline sand, styloids, spherical, or drop-like structures. Considering their lower flow and totally blocked vessels, both Hencha and Khamri confirmed their susceptibility to environmental constraints. However, Sakasly, Razegui1, and Razegui2 cultivars presented higher tolerance according to their sap flow and xylem morphology. [ABSTRACT FROM AUTHOR]

The electron beam of an environmental scanning electron microscope is used to manipulate gold nanoparticles (AuNPs) at the liquid‐vapor interface of their aqueous dispersion. Controlled motion and agglomeration of AuNPs into larger structures is achieved, enabling the writing of superstructures that float at the interface. AuNPs move toward the electron beam, independent of zeta potential, and the spatial range at which this attraction acts is much larger than what is possible for electrostatic interactions. The speed of agglomerate growth depends on the applied electron flux, and electron beam energy. The hypothesis that this electron beam‐induced AuNP assembly process is caused by local liquid evaporation upon electron beam heating is presented. [ABSTRACT FROM AUTHOR]

In this study, açaí‐loaded kefir microbial films obtained in solutions containing demerara sugar, a low‐cost and relatively organic sugar, were prepared. Environmental scanning electron microscopy (ESEM), atomic force microscopy (AFM), stereometric and multifractal analyses were applied to study the influence of the concentration of açaí over the surface morphology as well as its multifractal nature. The ESEM and AFM images showed that low concentrations of acai berry form surface covered by bacteria, while higher concentrations promote yeast growth. The autocorrelation function suggested that the degree of surface anisotropy changes as the concentration of açaí increases, while the Minkowski Functionals confirmed that the sample with the highest content has a different morphology than the samples containing 10–40 ml. The multifractal analysis revealed that the surfaces have a strong multifractal behavior, where the multifractal singularity strength was higher in the sample containing the highest concentration of açaí. The sample with the highest concentration was then mapped to have a greater vertical growth of its spatial patterns. These results prove that image analysis using mathematical tools can be very useful for the characterization of biological‐based systems for application in the biomedicine field. We characterized the micromorphology of the 3D surface of the kefir biofilms associated with Acai extract.The 3D surface analysis of the samples was performed using by environmental scanning electron microscope and atomic force microscopy.We determined the multifractal and Minkowski Functionals of the analyzed samples. [ABSTRACT FROM AUTHOR]

Background: Shade of the teeth is of specific significance to the patient because of social and psychological concern and hence plays vital role as primary care. Bleaching is a noninvasive, relatively inexpensive, conservative, and low-maintenance method to change a smile dramatically. Aim: To study the effect of application of three bleaching agents at different wavelengths of laser on the enamel surface of teeth using an environmental scanning electron microscopy (ESEM). Materials and Methods: One hundred and twenty freshly extracted, noncarious intact maxillary central incisors were collected and stored in moist conditions in plastic containers. Using a randomized stratified design, the samples were divided into 12 groups (n = 10). The bleaching agent was mixed according to the manufacturer's instructions and applied on the enamel surface of the teeth followed by laser activation. The ultrastructural effects of the bleaching agent on the enamel were determined with an ESEM. Samples were assessed both before and after bleaching on the basis of the degree of surface damage. Because the observation by ESEM was designed to be qualitative, no statistical analysis was performed. Results: JW power bleaching agent and Opalescence Xtra boost showed minimum surface alteration when compared to Polaoffice. Furthermore, the groups treated with diode 810 nm showed less surface damage while neodymium-doped yttrium aluminum garnet 1064 nm more surface alterations than the groups treated with diodes. Conclusion: From this current study, it can be concluded that the diode laser of 810 nm with JW power bleaching showed minimum surface alterations.

While polymer flooding improves oilfield recovery, it also produces a large amount of polyacrylamide wastewater (PAM). Polyacrylamide wastewater has the characteristics of a high degree of emulsification, high viscosity, and difficulty degrading. The treatment of polymer-containing sewage has become a research hotspot. In this paper, based on the dielectric barrier discharge (DBD) experiment, the effect of non-equilibrium plasma on the degradation rate and viscosity of PAM solution was studied by changing the discharge time, discharge voltage, and PAM solution concentration. At the same time, the environmental scanning electron microscopy was used to observe the PAM before and after discharge. As the morphology of the solution changed, the degradation products of PAM solution after discharge were detected by Fourier-transform infrared absorption spectrometer. The results show that under the conditions of a discharge voltage of 20 kV and a frequency of 10 kHz, the degradation rate of DBD to a PAM solution with a concentration of 1,000 mg/L can reach up to 89%. DBD can cause the PAM molecular chain to curl up and reduce its viscosity rapidly. DBD is produced as the active substance first broke the PAM macromolecular chain into small molecules. Further treatment can produce acrylamide monomer and acrylic acid. [ABSTRACT FROM AUTHOR]

Anisotropic growth of nanostructures from individual nickel nanoparticles was observed during in situ heating experiments in an environmental scanning electron microscope (ESEM) at 800°C under water vapor atmosphere. The morphology of nanostructures exhibited one directional growth with rates ranging below 1.8 nm/s. Energy dispersive X‐ray spectroscopy and selected area electron diffraction confirmed NiO stoichiometry of the growing nanostructures. Variations of the oxygen partial pressure during ex situ annealing and in situ ESEM heating experiments elucidate that anisotropic NiO growth is energetically favored in areas where the local surface energy density is relatively high. Growth of NiO nanostructures was absent in dry air and dry nitrogen environments and required the presence of water vapor. The results of this study suggest that the manipulation of surface energy prior to exposure to water vapor at elevated temperatures can prevent unwanted oxide nanostructure growth. [ABSTRACT FROM AUTHOR]

Background: Shade of the teeth is of specific significance to the patient because of social and psychological concern and hence plays vital role as primary care. Bleaching is a noninvasive, relatively inexpensive, conservative, and low-maintenance method to change a smile dramatically. Aim: To study the effect of application of three bleaching agents at different wavelengths of laser on the enamel surface of teeth using an environmental scanning electron microscopy (ESEM). Materials and Methods: One hundred and twenty freshly extracted, noncarious intact maxillary central incisors were collected and stored in moist conditions in plastic containers. Using a randomized stratified design, the samples were divided into 12 groups (n = 10). The bleaching agent was mixed according to the manufacturer's instructions and applied on the enamel surface of the teeth followed by laser activation. The ultrastructural effects of the bleaching agent on the enamel were determined with an ESEM. Samples were assessed both before and after bleaching on the basis of the degree of surface damage. Because the observation by ESEM was designed to be qualitative, no statistical analysis was performed. Results: JW power bleaching agent and Opalescence Xtra boost showed minimum surface alteration when compared to Polaoffice. Furthermore, the groups treated with diode 810 nm showed less surface damage while neodymium-doped yttrium aluminum garnet 1064 nm more surface alterations than the groups treated with diodes. Conclusion: From this current study, it can be concluded that the diode laser of 810 nm with JW power bleaching showed minimum surface alterations. [ABSTRACT FROM AUTHOR]

Pyrolysis is a promising technology to increase pore and fracture connectivity in oil shale and thereby accomplish commercial recovery of unconventional hydrocarbons. Herein, real-time oil shale pyrolysis dynamics are imaged at nanoscale via environmental scanning electron microscopy (imaging resolution of 58 nm/pixel, imaging speed of 1 frame per second, and heating temperature up to 750 °C). It is counterintuitively observed that 1) inorganic nano-fractures started to appear below 100 °C; 2) inorganic nano-fracture width had a non-monotonous relationship with temperature; and 3) organic kerogen areas decreased monotonously with increasing temperature. These findings will establish a standard benchmark for unconventional resource recovery, promote fundamental understanding of oil shale pyrolysis dynamics at nanoscale and provide key guidance on oil shale extraction at reservoir scale. • Real-time imaging of oil shale pyrolysis dynamics is performed at nanoscale • The initial appearance and growth of nano-fractures are observed below 100 °C • A non-monotonous relationship between nano-fracture width and temperature is identified [ABSTRACT FROM AUTHOR]

Xylem vessels are essential pivotal organs in bulk hydraulic flow through the whole woody plant. However, environmental constraints generate disagreements in xylem structures, which are characterized by air emboli and occlusions formations, compromising water conductivity in grapevines. The aim of this work was to explore xylem morphology dynamics through the xylem sap flow of five Tunisian grapevine cultivars during the natural bleeding sap periods of 2019, 2021, and 2022. In fact, Sakasly, Khamri, Hencha, Razegui1, and Razegui2 rain-fed grapevine cultivars revealed differential responses towards xylem sap movement. The results demonstrated that the xylem sap flow was significantly more abundant in 2019 than 2021 and 2022 bleeding sap campaigns. A variation was revealed between the cultivars regarding the xylem sap flow. In fact, Sakasly gave the best xylem flow during the three campaigns. Razegui1 and Razegui2 registered approximately similar xylem sap flow, while Hencha and Khamri present the lowest sap fluxes during the three campaigns. Moreover, several vascular occlusions forms were identified from stem cross sections using environmental scanning electron microscopy (ESEM), including tyloses, gels, starch, and gum deposits. The highest occlusion number was observed in Sakasly, Razegui1, and Razegui2 cultivars. Among different biogenic calcium shapes, several were observed for the first time in grapevine, including multi-faceted druse, cubic, crystalline sand, styloids, spherical, or drop-like structures. Considering their lower flow and totally blocked vessels, both Hencha and Khamri confirmed their susceptibility to environmental constraints. However, Sakasly, Razegui1, and Razegui2 cultivars presented higher tolerance according to their sap flow and xylem morphology.

Abstract Environmental scanning electron microscopy (ESEM) is a powerful technique that enables imaging of diverse specimens (e.g., biomaterials, chemical materials, nanomaterials) in a hydrated or native state while simultaneously maintaining micro‐to‐nanoscale resolution. However, it is difficult to achieve high signal‐to‐noise and artifact‐free secondary electron images in a high‐pressure gaseous environment due to the intensive electron‐gas collisions. In addition, nanotextured substrates can mask the signal from a weakly scattering sample. These drawbacks limit the study of material dynamics under extreme conditions and correspondingly our understanding in many fields. In this work, an imaging framework called Quasi‐Newtonian ESEM is proposed, which introduces the concepts of quasi‐force and quasi‐work by referencing the scattering force in light–matter interactions, to break these barriers without any hardware changes. It is shown that quasi‐force is a more fundamental quantity that has a more significant connection with the sample morphology than intensity in the strongly scattering regime. Experimental and theoretical studies on the dynamics of droplet condensation in a high‐pressure environment (up to 2500 Pa) successfully demonstrate the effectiveness and robustness of the framework and that the overwhelmed signal of interest in ESEM images can be reconstructed through information stored in the time domain, i.e., frames captured at different moments.

We report, for the first time, the surprising presence of toxic nanoparticles, especially silver, in the brain of a fetus, who died unexpectedly at the end of a regular pregnancy. After an accurate autopsy, including the examination of the fetal annexes, an in-depth anatomopathological study of the nervous system and a search by scanning electron microscopy of nanoparticles in the brain, we highlighted the sequence of events that may have led to this fetal death, triggered primarily by the transition of nanosized xenobiotics from the mother to the fetal bloodstream. From this report emerges the importance of considering the search of nanosubstances in the brain during routine investigations following unexpected and unexplained fetal and infant deaths. Despite the progress in medical diagnostics and antenatal care, one-half to two-thirds of stillbirths occur for unknown reasons. In this article we report the presence of toxic nanoparticles of silver and other metals in the brain of a baby who died unexpectedly at the end of a regular pregnancy. The presence of these particles may be attributed to the increasing use of nanomaterials in biomedicine, biotechnology and industries with environmental impacts. These substances can enter the fetal bloodstream from the pregnant mother's circulation via the placenta. From here, the nanoparticles can accumulate in specific regions of the fetal brain, causing developmental dysfunction. We conclude that it is important to expand the guidelines for investigating unexplained stillbirths by including the research of toxic nanosized pollutants in the fetal brain. [ABSTRACT FROM AUTHOR]

Material characterization of brittle and ductile materials, by means of determining characteristic material parameters such as hardness, elastic moduli or yield strength, is of significance to the scientific community. The evaluation of indentations on micro- and macro-scale can be employed to characterize materials but is governed by highly sensitive acquisition hardware and complex analysis. Profound analytical, experimental, and numerical approaches exist to evaluate the impact of spherical indenters on a plane surface but require a deep knowledge of plasticity and computational mechanics. This work aims to provide a generalized analysis tool, which is based on fundamental Newtonian mechanics, to be applied on brittle and ductile materials of homogeneous and heterogeneous constitution. Based on bouncing ball measurements, the coefficient of restitution is evaluated to determine the homogeneity and degree of plasticity of the selected material. The measurements are supported with additional physical (e.g., electron micrographs, velocimetry) and numerical (Finite Element) investigations. It can be demonstrated that the evaluation of the bouncing trajectories provides essential information on the plasticity and topology of the selected material and leads to adequate results compared to complex experimental and numerical analysis. [ABSTRACT FROM AUTHOR]

Environmental scanning electron microscopy (ESEM) is a powerful technique that enables imaging of diverse specimens (e.g., biomaterials, chemical materials, nanomaterials) in a hydrated or native state while simultaneously maintaining micro‐to‐nanoscale resolution. However, it is difficult to achieve high signal‐to‐noise and artifact‐free secondary electron images in a high‐pressure gaseous environment due to the intensive electron‐gas collisions. In addition, nanotextured substrates can mask the signal from a weakly scattering sample. These drawbacks limit the study of material dynamics under extreme conditions and correspondingly our understanding in many fields. In this work, an imaging framework called Quasi‐Newtonian ESEM is proposed, which introduces the concepts of quasi‐force and quasi‐work by referencing the scattering force in light–matter interactions, to break these barriers without any hardware changes. It is shown that quasi‐force is a more fundamental quantity that has a more significant connection with the sample morphology than intensity in the strongly scattering regime. Experimental and theoretical studies on the dynamics of droplet condensation in a high‐pressure environment (up to 2500 Pa) successfully demonstrate the effectiveness and robustness of the framework and that the overwhelmed signal of interest in ESEM images can be reconstructed through information stored in the time domain, i.e., frames captured at different moments. [ABSTRACT FROM AUTHOR]

This paper reports on improved techniques to create and characterize nanometre‐sized droplets from dilute aqueous solutions by using a gas dynamic virtual nozzle (GDVN). It describes a method to measure the size distribution of uncharged droplets, using an environmental scanning electron microscope, and provides theoretical models for the droplet sizes created. The results show that droplet sizes can be tuned by adjusting the gas and liquid flow rates in the GDVN, and at the lowest liquid flow rates, the size of the water droplets peaks at about 120 nm. This droplet size is similar to droplet sizes produced by electrospray ionization but requires neither electrolytes nor charging of the solution. The results presented here identify a new operational regime for GDVNs and show that predictable droplet sizes, comparable to those obtained by electrospray ionization, can be produced by purely mechanical means in GDVNs. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the shear bond strength (SBS) and interface between a resin composite and a new high-viscous glass ionomer cement (HV-GIC), a HV-GIC, a resin-modified glass ionomer cement (RM-GIC), a bulk-fill flowable composite, and a regular flowable composite bonded with various adhesive systems. Methods and materials: A resin composite (Filtek Z350) was bonded to a new HV-GIC (EQUIA Forte Fil) using various adhesive systems, including a universal adhesive in self-etch and etch-and-rinse mode (Scotchbond Universal), a two-step etch-and-rinse adhesive (Scotchbond 1-XT), a one-step self-etch adhesive (Optibond All-in-one) tested also after silane application (Monobond Plus), and a coating material (EQUIA Forte Coat). The resin composite was also bonded to a HV-GIC (Fuji IX GP), a RM-GIC (Fuji II LC), a bulk-fill flowable composite (SDR), and a regular flowable composite (Tetric Evo Flow) with the universal adhesive in self-etch mode (Scotchbond Universal). Two-way ANOVA followed by Dunnett's post hoc test was used to investigate the difference in SBS. Failures were analyzed by chi-square test. Bonding interfaces were examined by environmental scanning electron microscopy (E-SEM). Results: SBS to EQUIA Forte Fil was significantly lower with Scotchbond 1-XT than with all other adhesive systems. By using Scotchbond Universal with the self-etch technique, the SBS to EQUIA Forte Fil was significantly higher than the SBS to Fuji IX GP and significantly lower than the SBS to Fuji II LC, SDR, and Tetric Evo Flow. E-SEM images showed an intimate contact at all interfaces examined. Conclusion: EQUIA Forte Fil showed satisfactory SBS and interfaces with all adhesives tested. Clinical relevance: Bonding between the resin composite and HV-GIC can be achieved using a universal adhesive in self-etch mode, an easy-to-use adhesive system. [ABSTRACT FROM AUTHOR]

Background and objectives: Particle size distribution and damaged starch content have a major impact on flour quality because they influence the behavior of flour during hydration in processing. Particle size distribution and starch damage of legume flours and their relationship during grinding have not been evaluated. The standard enzymatic method for the measurement of damaged starch content (AACC 76‐31) was used to find a new calibration equation for the rapid amperometric method (SDmatic, AACC 76‐33.01) for legume flours. Changes in particle size distribution and starch damage during regrinding in a commercial pea flour were compared with those in a commercial wheat flour. Findings: Legume flours had a smaller damaged starch content (0.8–4.7 SD%) than wheat flours (2.2–7.0 SD%). The bimodal particle size distribution of flours was linked to structural elements as confirmed by environmental scanning electron microscopy and laser granulometry. Particle size distribution and starch damage varied concomitantly during regrinding in the commercial pea flour as in the commercial wheat flour. The main factor responsible for the increase in damaged starch content was an increase in the proportion of the fine fraction in the flour. Fine fractions contained higher damaged starch contents than coarse fractions. Conclusions: Hypotheses concerning differences in fragmentation mechanisms in the two flours were formulated, suggesting that pea flour has a higher likelihood for fracture but less tendency to produce damaged starch than wheat flour. Significance and novelty: The amperometric method (AACC 76‐33.01) can be used for a rapid estimation of the damaged starch content in legume flours. Furthermore, the results suggest a lower hardness of pea flour material compared to wheat flour material that would have a significant impact on milling strategies. [ABSTRACT FROM AUTHOR]

Abstract The effect of Basil Seed Gum (BSG) on native and pre-gelatinized corn starch and flour gels was evaluated. With this purpose, the hydration, pasting, rheological, textural and microstructural properties of the mixed gels were analyzed. Xanthan was used as a comparison, as it presents comparable high zero shear viscosity to BSG. The presence of BSG led to greater water binding capacity and greater water absorption index of the starch and flours compared to the free-gum systems. In general BSG substantially increased the peak and final viscosities of the pastes, also leading to a raise in the viscoelasticity (G' and G") and hardness of the final gels, native or treated (pregelatinized starch and extruded flour). A more opened microstructure—compared to a homogeneous and dense matrix of the control native starch gels— with strands and a spider-like network of BSG across the pockets was detected. On the other hand, xanthan showed the opposite effect, decreasing the peak and final viscosities of the native systems, delaying the gelatinization process, and also leading to weaker gels of reduced viscoelasticity with opened honeycomb-like microstructures. However, for pregelatinized flour and starch the effect of xanthan was minimal. Graphical abstract Image 1 Highlights • Basil Seed Gum (BSG) and xanthan showed opposite behavior during starch gelation. • BSG led to a high water binding and absorption capacity of starch and flours. • BSG resulted in stronger gels in all native and pregelatinized systems. • Opened structures with strands (BSG) and honeycomb-like ones (xanthan) were observed. [ABSTRACT FROM AUTHOR]

Abstract Pasta industry has introduced in the market new pasta formulations to respond to consumers' nutritional/health needs. The resulting macromolecular, mesoscopic, and microscopic changes induced in pasta need to be evaluated. In this work, a multi-scale screening of physico-chemical properties was performed on commercial pasta formulations (wheat semolina, whole wheat semolina, veggie, gluten free). Pasta samples showed significantly (p ≤ 0.05) different properties: wheat semolina and whole flour samples had a more pronounced viscoelastic behaviour (Dynamic Mechanical Analysis), higher hardness (Texture Analysis) and higher mobility of the more rigid protons (1H Nuclear Magnetic Resonance); veggie pasta had the highest frozen water content and higher 1H T 2 molecular mobility; gluten free pasta showed a larger rigid population (Population C). This study indicated the ability of a multi-scale approach in discriminating pastas' formulation. Besides physico-chemical properties, 1H NMR was particularly able to properly discriminate pastas' formulations. Highlights • A multi-scale screening of physico-chemical properties of pasta was performed. • Wheat semolina, whole wheat semolina, veggie, and gluten free pasta were evaluated. • Unconventional DMA and TD-NMR Relaxometry techniques were used. • 1H TD-NMR Relaxometry was a valid tool to describe pasta properties. [ABSTRACT FROM AUTHOR]

To be able to use lead acid batteries in particularly difficult conditions in the mining industry, it is very important to understand the events that occur during traction operation of mining carts, or auxiliary lighting. Failure of lead accumulators in the hazardous environments, where it is desired non-explosive embodiment, may have fatal consequences. The paper describes the possibility of observing changes in active materials at the microscopic level. The process of charging and discharging lead-acid accumulator has been described in many publications. The aim of this article is to supplement known information about a series of images and analysis that will accurately show progressive changes in the structure of the negative electrode. Negative electrodes are, at each cycle, charged and discharged under the same conditions, scanned with a scanning electron microscope, the elemental analysis (EDS) is performed, and the size of the individual sulfate crystals is measured. Previously measured results indicate that during the charging the conversion of PbSO4 crystals into a charged form of the active mass is not complete, and there is a rapid increase in the size of lead sulfate crystals on the negative electrode. This article compares changes in electrode surface composition after two cycles. There is a clear loss of lead and, on the other hand, the visible growth of sulfur. This indicates progressive surface sulfation.

Purpose: To evaluate by Environmental Scanning Electron Microscopy (ESEM) the corneal incision architecture after intraocular lens (IOL) implantation in pig eyes, using manual, automated injectors or preloaded delivery systems.Methods: Twenty-four pig eyes underwent IOL implantation in the anterior chamber using three different injectors: manual (Monarch III) (n = 8), automated (AutoSert) (n = 8), or a preloaded system (UltraSert) (n = 8). Acrysof IQ IOLs, 21 Dioptres (D) (n = 12) and 27D (n = 12), were implanted through 2.2 mm clear corneal incisions. Incision width was measured using corneal calipers. The endothelial side of the incision was analyzed with ESEM.Results: In each group, the final size of the corneal wound after IOL implantation, measured by calipers, was 2.3-2.4 mm. The incision architecture resulted more irregular in the Monarch group compared with the other injectors. In every group the 27D IOL-implanted specimens showed more alterations than in 21D IOL-implanted samples, and this was less evident in the UltraSert group. The Descemet tear length was higher in the Monarch group than AutoSert and UltraSert group.Conclusions: The automated and preloaded delivery systems provided a good corneal incision architecture; after high-power IOL implantation the incisions were more regular and less damaged with the preloaded system than with the other devices. [ABSTRACT FROM AUTHOR]

Initial-stage oxidation characteristics of a γ-TiAl alloy were investigated by using in situ environmental scanning electron microscopy for both heating and isothermal oxidation processes. Selective oxidation led to primary nucleation and growth on the aluminum-rich γ phase. Under different isothermal oxidation times, the oxide morphology changed to a linear structure between 750 °C and 774 °C and to an acicular structure at 800 °C. The initial oxidation process of γ-TiAl alloy could be divided into three stages: nucleation; growth; and morphological transformation and subsequent growth stages. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy has been used to observe and study parasitic protozoa for at least 40 years. However, field emission electron sources, as well as improvements in lenses and detectors, brought the resolution power of scanning electron microscopes (SEM) to a new level. Parallel to the refinement of instruments, protocols for preservation of the ultrastructure, immunolabeling, exposure of cytoskeleton and inner structures of parasites and host cells were developed. This review is focused on protozoan parasites of medical and veterinary relevance, e.g., Toxoplasma gondii , Tritrichomonas foetus , Giardia intestinalis , and Trypanosoma cruzi , compilating the main achievements in describing the fine ultrastructure of their surface, cytoskeleton and interaction with host cells. Two new resources, namely, Helium Ion Microscopy (HIM) and Slice and View, using either Focused Ion Beam (FIB) abrasion or Microtome Serial Sectioning (MSS) within the microscope chamber, combined to backscattered electron imaging of fixed (chemically or by quick freezing followed by freeze substitution and resin embedded samples is bringing an exponential amount of valuable information. In HIM there is no need of conductive coating and the depth of field is much higher than in any field emission SEM. As for FIB- and MSS-SEM, high resolution 3-D models of areas and volumes larger than any other technique allows can be obtained. The main results achieved with all these technological tools and some protocols for sample preparation are included in this review. In addition, we included some results obtained with environmental/low vacuum scanning microscopy and cryo-scanning electron microscopy, both promising, but not yet largely employed SEM modalities. [ABSTRACT FROM AUTHOR]

The evolution of argillaceous rock suffering from desaturation/resaturation is a key factor that affects the safety of deep geological repositories of radioactive waste. However, the behavior of this rock when resaturated to nearly 100% relative humidity (RH) has been poorly studied, because water condensation was frequently encountered in the conventional RH-control technique. This issue has been overcome in the present work using an environmental scanning electron microscope (ESEM) that provides improved RH control. The recorded micrographs subsequently were analyzed for full-field strain measurement using digital-image correlation techniques. The results reveal that the swelling (the sample in the size of several millimeters) attained stability in less than an hour during the 30%–80% RH step; however, the swelling strain continued to rise for up to 10h during the 80%–99% RH step. The anomalous time-dependent swelling at nearly 100% RH is not explicable in terms of hydraulic flow or propagation of swelling-induced microcracks. The evolution of strain fields shows that the areas of continuous swelling are located mainly inside the clay matrix. We suggest that the creep-like swelling of clay might be related to an osmotic flow (driven by a solute-concentration gradient) that dissipates more slowly than the hydraulic flow (driven by pressure gradient). The existence of time-dependent swelling in argillaceous rock under resaturated conditions should be considered for the reliability assessment of long-term radioactive waste disposal. [ABSTRACT FROM AUTHOR]