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Liver dysfunction is the main cause of hepatic encephalopathy. However, histopathological changes in the brain associated with hepatic encephalopathy remain unclear. Therefore, we investigated pathological changes in the liver and brain using an acute hepatic encephalopathy mouse model. After administering ammonium acetate, a transient increase in the blood ammonia level was observed, which returned to normal levels after 24 h. Consciousness and motor levels also returned to normal. It was revealed that hepatocyte swelling, and cytoplasmic vacuolization progressed over time in the liver tissue. Blood biochemistry also suggested hepatocyte dysfunction. In the brain, histopathological changes, such as perivascular astrocyte swelling, were observed 3 h after ammonium acetate administration. Abnormalities in neuronal organelles, especially mitochondria and rough endoplasmic reticulum, were also observed. Additionally, neuronal cell death was observed 24 h post-ammonia treatment when blood ammonia levels had returned to normal. Activation of reactive microglia and increased expression of inducible nitric oxide synthase (iNOS) were also observed seven days after a transient increase in blood ammonia. These results suggest that delayed neuronal atrophy could be iNOS-mediated cell death due to activation of reactive microglia. The findings also suggest that severe acute hepatic encephalopathy causes continued delayed brain cytotoxicity even after consciousness recovery.

Cotton fibers, as highly extended, thickened epidermal seed structures, are a crucial renewable resource in textile production. Cotton plants produce two main types of fiber cells: wide, hemisphere-shaped fibers and narrow, tapered fibers. Both types stabilize through secondary cell wall development, with the mature narrow fibers being particularly valued for spinning into fine, strong yarns, suitable for premium cotton fabrics. Traditional methods for studying fiber development and cell types, such as scanning electron microscopy (SEM), are often time-intensive and costly. SEM preparation steps, including fixation, dehydration, and sputter coating, can cause shrinkage and other image distortions, limiting the accuracy of observations. Variable-pressure scanning electron microscopy (VP-SEM) offers an alternative approach, operating under low pressure rather than a high-vacuum environment, which can be advantageous for imaging live samples with minimal sample preparation. In this study, we applied VP-SEM to observe fiber cell initiation and early elongation in the conventional upland cotton cultivar UGA 230 at 0 and 1-day post-anthesis. Two SEM detectors, the ultra-variable-pressure detector and backscattered electrons, were used to capture detailed images. Optimal imaging conditions were identified with a 15 keV accelerating voltage and a 50 Pa pressure setting, enabling clear visualization of early fiber development without the need for extensive preparation. This VP-SEM protocol not only facilitates high-resolution imaging of cotton fibers at early developmental stages but also reduces time and expense, minimizing sample damage. Additionally, this optimized approach can be adapted for other fresh biological samples, making it a versatile tool for real-time imaging across various studies in plant biology and beyond.

Low-fat meat products always have harder texture, lower juiciness, and worse flavor. Due to their higher water-holding, water absorption, and organic molecule absorption, chia seeds (CHIA) have been applied in powders, nutrition bars, breads, and cookies. Hence, the objectives of this study were to: (1) analyze the nutritional compositions in CHIA; and (2) look for the possible application of CHIA on restructured ham-like products. CHIA has high amounts of α-linolenic acid, crude polysaccharides, and also contains essential amino acids, minerals, and polyphenols. Regarding processing properties of CHIA, a combination of CHIA and carrageenan (CA) increased (p<0.05) production yield of restructured ham-like products. A scanning electron microscope observation indicated that CHIA and CA addition can assist an emulsification in this ham-like product. Addition of 0.5% CA and 1.0% CHIA in this ham-like product showed the similar overall acceptance as products with added fat. Following storage at 4°C, higher (p<0.05) purge and centrifugation losses, as well as hardness of this ham-like product can be improved by adding CHIA and CA. CHIA addition also resulted in lower (p<0.05) lipid and protein oxidation, especially a 1.0% addition. In summary, due to both nutritional addition and improvements on physicochemical and sensorial properties of restructured ham-like products, CHIA seeds have great potential on the development of healthy and good-quality meat products. [Display omitted] •Chia seeds (CHIA) have high amounts of α-linolenic acid and crude polysaccharides.•CHIA is a good daily supplement for achieving the daily reference intakes of essential amino acids and minerals.•Rutin and hesperidin are the major flavonoids in CHIA.•CHIA addition can improve processing properties of restructured ham-like products.•CHIA addition retards lipid/protein oxidation of restructured ham-like products on storage (4°C).

This book contains proposals to redesign the scanning electron microscope, so that it is more compatible with other charged particle beam instrumentation and analytical techniques commonly used in surface science research. It emphasizes the concepts underlying spectrometer designs in the scanning electron microscope, and spectrometers are discussed under one common framework so that their relative strengths and weaknesses can be more readily appreciated. This is done, for the most part, through simulations and derivations carried out by the author himself. The book is aimed at scientists, engineers and graduate students whose research area or study in some way involves the scanning electron microscope and/or charged particle spectrometers. It can be used both as an introduction to these subjects and as a guide to more advanced topics about scanning electron microscope redesign.

Ultrathin sections of rice leaf blades observed two-dimensionally using a transmission electron microscope (TEM) show that the chlorenchyma is composed of lobed mesophyll cells, with intricate cell boundaries, and lined with chloroplasts. The lobed cell shape and chloroplast positioning are believed to enhance the area available for the gas exchange surface for photosynthesis in rice leaves. However, a cell image revealing the three-dimensional (3-D) ultrastructure of rice mesophyll cells has not been visualized. In this study, a whole rice mesophyll cell was observed using a focused ion beam scanning electron microscope (FIB-SEM), which provides many serial sections automatically, rapidly and correctly, thereby enabling 3-D cell structure reconstruction. Rice leaf blades were fixed chemically using the method for conventional TEM observation, embedded in resin and subsequently set in the FIB-SEM chamber. Specimen blocks were sectioned transversely using the FIB, and block-face images were captured using the SEM. The sectioning and imaging were repeated overnight for 200-500 slices (each 50 nm thick). The resultant large-volume image stacks ( x = 25 μm, y = 25 μm, z = 10-25 μm) contained one or two whole mesophyll cells. The 3-D models of whole mesophyll cells were reconstructed using image processing software. The reconstructed cell models were discoid shaped with several lobes around the cell periphery. The cell shape increased the surface area, and the ratio of surface area to volume was twice that of a cylinder having the same volume. The chloroplasts occupied half the cell volume and spread as sheets along the cell lobes, covering most of the inner cell surface, with adjacent chloroplasts in close contact with each other. Cellular and sub-cellular ultrastructures of a whole mesophyll cell in a rice leaf blade are demonstrated three-dimensionally using a FIB-SEM. The 3-D models and numerical information support the hypothesis that rice mesophyll cells enhance their CO 2 absorption with increased cell surface and sheet-shaped chloroplasts.

Improvement of reliable and eco-friendly process for synthesis of metallic nanoparticles is a significant step in the field of application nanotechnology. One approach that shows vast potential is based on the biosynthesis of nanoparticles using micro-organisms. In this study, biosynthesis of silver nanoparticles (AgNP) using 30 cyanobacteria were investigated. Cyanobacterial aqueous extracts were subjected to AgNP synthesis at 30 °C. Scanning of these aqueous extracts containing AgNP in UV–Visible range showed single peak. The λ max for different extracts varied and ranged between 440 and 490 nm that correspond to the “plasmon absorbance” of AgNP. Micrographs from scanning electron microscope of AgNP from cyanobacterial extracts showed that though synthesis of nanoparticles occurred in all strains but their reaction time, shape and size varied. Majority of the nanoparticles were spherical. Time taken for induction of nanoparticles synthesis by cyanobacterial extracts ranged from 30 to 360 h and their size from 38 to 88 nm. In terms of size Cylindrospermum stagnale NCCU-104 was the best organism with 38 and 40 nm. But in terms of time Microcheate sp. NCCU-342 was the best organism as it took 30 h for AgNP synthesis.

Restorative materials and techniques have improved the clinical success of a variety of restorative procedures. Despite these new improvements, microleakage remains one of the leading causes of restoration failure and may lead to postoperative sensitivity, enamel microcracks, marginal staining, discoloration, recurrent caries, and deformation of teeth. This study evaluated microleakages of five recent resin composites in class V cavities. Standardized class V cavities were prepared on the labial surfaces of one hundred extracted intact and noncarious human permanent premolar teeth. The cavities were divided into five groups (n=20) according to the resin composite material. Groups: A1, A2, A3, A4 and A5 were restored with Omnichroma, Spectrum, Mosaic, Tetric N-Ceram and Harmonize, respectively. The teeth were stained with methylene blue and then sectioned, and the extent of dye penetration was examined under a stereomicroscope and scanning electron microscope (SEM) to evaluate microleakage. One-way ANOVA test was used to statistically analyze the data. Statistical Package for Social Sciences Computer Software (SPSS) version 15.0 was used. Dye penetration was observed at the tooth-restoration interface in all the studied samples, with varying degrees of penetration. At the cervical margins of the cavities, no statistically significant difference in the microleakage scores was observed (P=0.16). At the cavity floor, no statistically significant difference in microleakage scores was observed (P=0.74). Omnichroma resin composite had the highest microleakage results. Nanohybrid resin composites showed less microleakage than other resin composites. Among all the groups, Omnichroma showed the highest microleakage at the cavity floor and at the cervical areas. In light of our findings, nanohybrid resin composites appear to be capable of reducing microleakage, and the results reported herein must be verified by additional clinical trials.

Background： Vulvovaginal candidiasis is caused by Candida albicans. The vaginal epithelium, as the first site of the initial stage of infection by pathogens, plays an important role in resisting genital tract infections. Moreover, lactobacilli are predominant members of the vaginal microbiota that help to maintain a normal vaginal microenvironment. Therefore, Lactobacillus crispatus was explored for its capacity to intervene in the immune response of vaginal epithelial cells VK2/E6E7 to C. albicans. Methods： We examined the interleukin-2 （IL-2）, 4, 6, 8, and 17 produced by VK2/E6E7 cells infected with C. albicans and treated with L. crispatus in vitro. The capacity ofL. crispatus to adhere to VK2/E6E7 and inhibit C. albicans growth was also tested by scanning electron microscopy （SEM） and adhesion experiments. Results： Compared with group VK2/E6E7 with C. albicans, when treated with L. crispatus, the adhesion of C. albicans to VK2/E6E7 cells decreased significantly by 52.87 ± 1.22%, 47.03 ± 1.35%, and 42.20 ± 1.55% under competition, exclusion, and displacement conditions, respectively. SEM revealed that the invasion of C. albicans into VK2/E6E7 cells was caused by induced endocytosis and active penetration. L. crispatus could effectively protect the cells from the virulence ofhyphae and spores of C. albicans and enhance the local immune function of the VK2/E6E7 cells. The concentrations of IL-2, 6, and 17 were upregulated significantly （P 〈 0.0 1） and that of IL-8 were downregulated significantly （P 〈 0.0 1） in infected VK2/E6E7 cells treated with L. crispatus. The concentration of IL-4 was similar to that of the group VK2/ E6E7 with C. albicans （24.10 ± 0.97 vs. 23.12 ±0.76 pg/ml, P= 0.221）. Conclusions： L. crispatus can attenuate the virulence of C. albicans, modulate the secretion of cytokines and chemokines, and enhance the immune response of VK2/E6E7 cells in vitro. The vaginal mucosa has a potential function in the local immune responses against pathogens that can be promoted by L. crispatus.

The 2D Janus transition‐metal dichalcogenides (TMDs) and alloyed TMDs are a widely studied emerging class of 2D materials that have been extensively used in electronic devices because of their excellent electronic, optical, and mechanical properties. The properties and behaviors of 2D‐materials‐based devices, such as the electrical breakdown caused by structural failure, are significant issues that have drawn considerable attention. In this study, the electrical behavior of polymorphic molybdenum sulfide selenide (MoSSe) devices is studied via in situ biasing experiments and recorded using transmission electron microscopy (TEM) at the atomic scale. The selenization temperature is a key factor in the phase transition of the material, which further affects the electrical and mechanical properties of MoSSe. The effects of electron‐beam irradiation and bias voltage are also discussed through a combination of experiments and theory. Quantifying the defect coverage and defect size also helps us to understand the behavior of material degradation. Furthermore, Cs‐corrected scanning TEM is utilized to identify the evolution of the morphology. The fracture morphology of the synthesized structure also varies with the application of high voltage. The cracks and defects caused by Joule heating are studied in terms of fracture type and size. Janus and alloy polymorphic monolayer molybdenum sulfide selenide (MoSSe) prepared at different selenization temperatures exhibits different electrical and mechanical properties after biasing. In the structural degradation of MoSSe, powerful in situ transmission electron microscope (TEM) and annular dark‐field scanning TEM are used to understand the individual effects of electron beams and bias.

The problems of measuring the dimensions of relief elements on a scanning electron microscope (SEM) in the technological process of manufacturing microcircuits are considered. The first problem is related to the fact that the increase in the SEM during operation can vary over a wide range depending on the measured dimensions. The second problem is that the probe diameter determined in the SEM calibration process differs from the diameter used in operational measurements. The third problem is related to the fact that it is not known which relief parameter is measured in the SEM probe defocusing method. It is shown that to solve the first problem, it is necessary to calibrate the mark on the image using structures with a trapezoidal profile and large angles of inclination of the side walls. The solution of the second problem is based on the method of defocusing the SEM probe: determining the dependence of the sizes between certain points on the SEM signals on the probe diameter and extrapolating this dependence to the zero value of the diameter. The third problem is solved with the help of a virtual scanning electron microscope.