Microscopy Research and Technique最新文献

This study aims to find out how the crystallinity quality, surface morphology, and mechanical performances change with the substitution of yttrium (Y) for bismuth (Bi) impurity within molar ratios of 0.00 ≤ x ≤ 0.12 in the Bi_2.0-xY_xSr_2.0Ca_1.1Cu_2.0O_y (Bi-2212) cuprates to reveal the dependence of micro surface topology on the substitution mechanism and achieve a strong relation between the impurity ions and crystallization mechanism. The materials are prepared by ceramic method. It is found that all the experimental findings improve remarkably with increasing yttrium impurity molar ratio of x = 0.01. Scanning electron microscopy (SEM) images indicate that the optimum Y ions strengthen the formation of flaky adjacent stacked layers due to the changes of thermal expansion, vibration amplitude of atoms, heat capacitance, reaction kinetics, activation energy, nucleation temperature, thermodynamic stability, and intermolecular forces. Besides, new engineering novel compound produced by optimum Y ions presents the best crystallinity quality, uniform surface view, greatest coupling interaction between grains, largest particle size distributions/orientations, and densest/smoothest surface morphology. Hardness measurement results totally support the surface morphology view. Moreover, mechanical design properties and durability of the tetragonal phase improve significantly with increasing replacement level of x = 0.01 due to the induction of new surface residual compressive stress areas, slip systems, and chemical bonding between the foreign and host atoms. Besides, the same sample exhibits the maximum strength and minimum sensitivity to loads depending on reduction of stored internal strain energy and degree of granularity. Consequently, cracks tend to propagate predominantly within the transcrystalline regions. Furthermore, each material investigated exhibits the characteristic behavior of the indentation size effect. In summary, the optimum Y-doped Bi-2212 sample paves the way for the expanded use of engineering ceramics across various applications based on the enhanced service life. RESEARCH HIGHLIGHTS: The presence of the optimum yttrium impurity significantly decreases the E_a value. As the Y/Bi replacement increases up to the molar substitution level of x = 0.01, the mechanical design properties and durability of the tetragonal phase enhance significantly.

Morchella is highly prized for its distinct and delicious taste, making it one of the most sought-after and valuable macrofungi. Despite Pakistan exporting morels to various European countries, Morchella's diversity in this South Asian country has not been cataloged using multilocus DNA sequence data. Realizing the need for their scientific identity, various collections were commissioned, including those from the low and high altitudinal zones of the Charsadda, Swat, and Poonch districts of Pakistan during autumn of 2015 through 2019. Specimens were identified by sequencing the internal transcribed spacer (ITS) region and portions of the RNA polymerase II largest subunit (RPB1), second largest subunit (RPB2), and translation elongation factor 1-α (TEF1) loci. Multigene molecular phylogenetic analysis revealed the autumnal collections were Morchella galilaea Masaphy & Clowez. The species was previously documented in the United States, China, Israel, and Turkey. A detailed taxonomic description, light and scanning electron microscopy, and multigene molecular phylogenetic analyses of the species are reported here for the first time from Pakistan. The study underscores the necessity for further surveys of unexplored areas of Pakistan and systematics of Morchella to augment species diversity and their geographic distribution. RESEARCH HIGHLIGHTS: Specimens of Morchella were collected from low and high altitudinal zones in Pakistan during the autumn. Specimens were assessed using multigene (ITS, RPB1, RPB2, and TEF1) molecular phylogenetic analyses for the first time in Pakistan. The specimens were identified as Morchella galilaea based on multigene molecular phylogenetic analysis. Updated taxonomic descriptions of macro- and microanatomical characters were provided for clarity and precision. Hitherto-unreported shapes of paraphyses and acroparaphyses are observed and thoroughly reported. Scanning electron microscopy (SEM) of an ascospore is provided.

Prototype optical microscopes, built to pursue developments in advanced imaging techniques, need specific opto-mechanical constructions: preferably with high flexibility in the elements' arrangement, easy access to the optical paths, straightforward integration with external optical subsystems-light sources and detectors-as well as good mechanical stability. Typically they are either built around an adapted commercial microscope body or as a home-brewed setups, based on standard opto-mechanical elements, and neither solution delivers the desired characteristics. We developed a series of versatile microscope design for prototype optical microscopes in various configurations that use folding mirror(s) to maintain the optical paths horizontal throughout most of the setup. All prototypes use many standard opto-mechanics in the excitation and detection paths, which simplifies the construction and maintenance of the microscopes. The proposed opto-mechanical arrangement proved to be useful in building an upright as well as inverted microscopes, in particular Raman microscopes in various configurations. Horizontal arrangement simplified greatly the optical alignment and enabled for fast modifications in the setup-both key advantages at the prototyping stage. Last but not least, the laser safety of the optical system increased. The versatile microscope platform, based around the idea of the horizontal beam arrangement, can easily be adopted to many microscope configurations and to a variety of components that potential users might want to incorporate into them. RESEARCH HIGHLIGHTS: We design, fabricate, and test a compact, versatile opto-mechanics for prototyping optical microscopes in various configurations. Horizontal layout along most of the optical paths provides excellent access to the light beams, allows for using standard components and increases the laser safety.

The aim of this study was to examine the dimensions and surface morphology of pollen grains of some sweet and sour cherry genotypes through scanning electron microscopy (SEM) as an additional alternative identification tool. In vitro pollen germination and pollen tube length as indicators of their viability were determined as well. Observations were carried on 10 sweet cherry (Prunus avium L.) and 7 sour cherry (Prunus cerasus L.) genotypes. All genotypes had prolate, tricolpate pollen grains, and striate exine ornamentation, with more parallel longitudinal ridges. Significant differences among genotypes within species and between species were found for most pollen grain characteristics and exine ornamentation. In both sweet and sour cherry the largest variability was recorded for colpus length (CV = 15.0% and 12.9%, respectively). For sweet cherry genotypes, in vitro pollen germination and pollen tube length ranged between 1.4% to 51.5% and 360.4 to 669.3 μm respectively, while for sour cherries they ranged from 15.5% to 37.0% and 96.3 to 960.2 μm, respectively. The results of the correlation analysis showed that in vitro pollen germination correlated positively with pollen length/pollen width (L/W) ratio (r = .640) and furrow width (r = .588), and negatively with the number of ridges (r = -.517), while pollen tube length was not significantly correlated with any of the studied characteristics. Principal component analysis (PCA) revealed that pollen length, pollen width, L/W ratio, colpus length, mesocolpium width, and ridge width are relevant tools to discriminate among the studied genotypes. The measurements made on pollen grains did not reveal individually big differences, but when all features were considered together, the pollen of each genotype exhibited a unique pattern. The distribution on the scatter plot showed considerable variation among sweet and sour cherry genotypes based on pollen morphological characteristics, which led to their distribution into two separate groups. This demonstrates the ability to distinguish cherry species based on pollen morphological characteristics determined by SEM. To improve discriminative ability for genotypes within species combination between pollen ultrastructural analysis, morphological and molecular markers is desirable, in subsequent work. RESEARCH HIGHLIGHTS: Significant differences in pollen characteristics between sweet and sour cherry. Significance of pollen morphology in taxonomic differentiation. Significance of SEM studies for the taxonomic identification.

One of the most popular fruits worldwide is the banana. Accurate identification and categorization of banana diseases is essential for maintaining global fruits security and stakeholder profitability. Four different types of banana leaves exist Healthy, Cordana, Sigatoka, and Pestalotiopsis. These types can be analyzed using four types of vision: RGB, night vision, infrared vision, and thermal vision. This paper presents an intelligent deep augmented learning model composed of VGG19 and passive aggressive classifier (PAC) to classify the four diseases types of bananas under each type of vision. Each vision consisted of 1600 images with a size of (224 × 224). The training-testing approach was used to evaluate the performance of the hybrid model on Kaggle dataset, which was justified by various methods and metrics. The proposed model achieved a remarkable mean accuracy rate of 99.16% for RGB vision, 98.02% for night vision, 96.05% for infrared vision, and 96.10% for thermal vision for training and testing data. Microscopy employed in this research as a validation tool. The microscopic examination of leaves confirmed the presence and extent of the disease, providing ground truth data to validate and refine the proposed model. RESEARCH HIGHLIGHTS: The model can be helpful for internet of things -based drones to identify the large scale of banana leaf-disease detection using drones for images acquisition. Proposed an intelligent deep augmented learning model composed of VGG19 and passive aggressive classifier (PAC) to classify the four diseases types of bananas under each type of vision. The model detected banana leaf disease with a 99.16% accuracy rate for RGB vision, 98.02% accuracy rate for night vision, 96.05% accuracy rate for infrared vision, and 96.10% accuracy rate for thermal vision The model will provide a facility for early disease detection which minimizes crop loss, enhances crop quality, timely decision making, cost saving, risk mitigation, technology adoption, and helps in increasing the yield.

Bioglasses are solid materials consisted of sodium oxide, calcium oxide, silicon dioxide and phosphorus in various proportions and have used in bone tissue engineering. There have been ongoing efforts to improve the surface properties of bioglasses to increase biocompatibility and performance. The aim of the present study is to modify the bioglass surface with an amino acid mixture consisting of arginine, aspartic acid, phenylalanine, cysteine, histidine and lysine, to characterize the surface, and to evaluate the performance and biocompatibility in vitro and in vivo. The untreated bioglass, bioglass kept in simulated body fluid (SBF), and modified bioglass were used in further evaluation. After confirmation of the surface modification with FT-IR analyses and SEM analyses, MC3T3-E1 preosteoblasts adhesion on the surface was also revealed by SEM. The modified bioglass had significantly higher ALP activity in colorimetric measurement, rate of calcium accumulations in Alizarin red s staining, lower rate of cell death in Annexin-V/PI staining to determine apoptosis and necrosis. Having higher cell viability rate in MTT test and absence of genotoxicity in micronucleus test (OECD 487), the modified bioglass was further confirmed for biocompatibility in vitro. The results of the rat tibial defect model revealed that the all bioglass treatments had a significantly better bone healing score compared to the untreated negative control. However, the modified bioglass exhibited significantly better bone healing efforts especially during the first and the second months compared to the other bioglass treatment treatments. As a result, the amino acid surface modification of bioglasses improves the surface biocompatibility and osteogenic performance that makes the amino acid modified bioglass a better candidate for bone tissue engineering. RESEARCH HIGHLIGHTS: Bioglass surface modification with amino acids contributes to bioglass-tissue interaction with an improved cell attachment. Modified bioglass increases in vitro Alp activity and calcium accumulation, and also positively affects cell behavior by supporting cell adaptation. Bioglass exerts osteogenic potential in vivo especially during early bone healing.

Electron microscopy is essential for examining materials and biological samples at microscopic levels, providing detailed insights. Achieving high-quality imaging is often challenged by the potential damage high-energy beams can cause to sensitive samples. This study compares scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to evaluate image quality, noise levels, and the ability to preserve delicate specimens. We used a modified SEM system with a transmitted electrons conversion accessory, allowing it to operate like a TEM but at lower voltages, thereby reducing sample damage. Our analysis included quantitative assessments of noise levels and texture characteristics such as entropy, contrast, dissimilarity, homogeneity, energy, and correlation. This comprehensive evaluation directly compared traditional TEM and the adapted SEM system across various images. The results showed that TEM provided images with higher clarity and significantly lower noise levels, reinforcing its status as the preferred method for detailed studies. However, the modified SEM system also produced high-quality images at very low acceleration voltages, which is crucial for imaging samples sensitive to high-energy exposure. The texture metrics analysis highlighted the strengths and limitations of each method, with TEM images exhibiting lower entropy and higher homogeneity, indicating smoother and more uniform textures. This study emphasizes the importance of selecting the appropriate electron microscopy method based on research needs, such as sample sensitivity and required detail level. With its conversion accessory, the modified SEM system is a versatile and valuable tool, offering a practical alternative to TEM for various applications. This research enhances our understanding of the capabilities and limitations of SEM and TEM. It paves the way for further innovations in electron microscopy techniques, improving their applicability for studying sensitive materials. RESEARCH HIGHLIGHTS: Our study introduces a modified SEM adapter enabling TEM-like imaging at reduced voltages, effectively minimizing sample damage without compromising image resolution. Through comparative analysis, we found that images from the modified SEM closely match the quality of traditional TEM, showcasing significantly lower noise levels. This advancement underscores the SEM's enhanced capability for detailed structural analysis of sensitive materials, broadening its utility across materials science and biology.

Diabetes mellitus causes impaired diabetic wounds which is linked to a number of pathological alterations that impede the healing of wounds. In the current research, Swiss albino mice were given alloxan monohydrate to induce diabetes and excision wounds of approximately 6 mm using biopsy punch. The diabetic wounds were treated with various biomaterials including Vachellia nilotica extract (VN), Nigella sativa extract (NS), V. nilotica nanoparticles (VNNPs) and N. sativa nanoparticles (NSNPs). Their effects were determined by evaluating the percent wound contraction, healing time, and histopathological analysis. The serum level of various biochemical parameters that is, pro-inflammatory cytokines,  Matrix metalloproteinases (MMPs) and tissue inhibitor matrix metalloproteinases (TIMPs) were also determined. VNNPs group provided the best outcomes, with wound contraction 100% on 12^th day. According to histopathological examination, VNNPs group reduced inflammation and encouraged the formation of blood vessels, fibroblasts, and keratinocytes. VNNPs group significantly alleviated the serum level of pro-inflammatory cytokines that are, TNF-α (19.4 ± 1.5 pg/mL), IL-6 (13.8 ± 0.6 pg/mL), and IL-8 (24.8 ± 1.2 pg/mL) as compared with the diabetic mice. The serum level of MMP2 (248.2 ± 7.9 pg/mL), MMP7 (316 ± 5.2 pg/mL), and MMP9 (167.8 ± 12.1 pg/mL) in the same group VNNPs were also observed much less than the diabetic mice. The serum level of TIMPs (176.8 ± 2.9 pg/mL) in the VNNPs group was increased maximally with respect to diabetic mice. It is concluded that nanoparticles and biomaterials possess healing properties and have the ability to repair the chronic/diabetic wound. RESEARCH HIGHLIGHTS: UV-spectrophotometric and Fourier transform infrared spectroscopy observation for functional group analysis and possible linkage between conjugates Optimization of the histopathological and biochemical markers after application of the formulations Microscopic analysis of epithelial tissues for evaluation of healing mechanisms Speedy contraction of wounds as the alleviation of the inflammatory and necrotic factors.