Deep ultraviolet based serial block-face imaging for three dimensional morphological assessment of the rodent brains

2021 ◽  
Author(s):  
Deepa Kasaragod ◽  
Meina Zhu ◽  
Hidenori Aizawa
2021 ◽  
pp. 021849232110304
Author(s):  
Mehrnoush Toufan ◽  
Zahra Jabbary ◽  
Naser Khezerlou aghdam

Background To quantify valvular morphological assessment, some two-dimensional (2D) and three-dimensional (3D) scoring systems have been developed to target the patients for balloon mitral valvuloplasty; however, each scoring system has some potential limitations. To achieve the best scoring system with the most features and the least restrictions, it is necessary to check the degree of overlap of these systems. Also the factors related to the accuracy of these systems should be studied. We aimed to determine the correlation between the 2D Wilkins and real-time transesophageal three-dimensional (RT3D-TEE) scoring systems. Methods This cross-sectional study was performed on 156 patients with moderate to severe mitral stenosis who were candidates for percutaneous balloon valvuloplasty. To morphologic assessment of mitral valve, patients were examined by 2D-transthoracic echocardiography and RT3D-TEE techniques on the same day. Results A strong association was found between total Wilkins and total RT3D-TEE scores (r = 0.809, p < 0.001). The mean mitral valve area assessed by the 2D and 3D was 1.07 ± 0.25 and 1.03 ± 0.26, respectively, indicating a mean difference of 0.037 cm2 (p = 0.001). We found a strong correlation between the values of mitral valve area assessed by 2D and 3D techniques (r = 0.846, p < 0.001). Conclusion There is a high correlation between the two scoring systems in terms of evaluating dominant morphological features. Partially, mitral valve area overestimation in the 2D-transthoracic echocardiography and its inability to assess commissural involvement as well as its dependence on patient age were exceptions in this study.


Author(s):  
Lijuan Huang ◽  
Zhengrui Hu ◽  
Hong Zhang ◽  
Yuanqiang Xiong ◽  
Shiqiang Fan ◽  
...  

Gallium oxide (Ga2O3) has been extensively studied in recent years because it is a natural candidate material for next-generation solar-blind deep ultraviolet photodetectors (PDs). Herein, a three dimensional (3D) amorphous...


Crystals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 82
Author(s):  
Mei Ge ◽  
Yi Li ◽  
Youhua Zhu ◽  
Meiyu Wang

The light extraction behavior of an AlGaN-based deep-ultraviolet LED covered with Al nanoparticles (NPs) is investigated by three-dimensional finite-difference time-domain simulation. For the transmission spectra of s- and p-polarizations in different emission directions, the position of maximum transmittance can be changed from (θ = 0°, λ = 273 nm) to (θ = 0°, λ = 286 nm) by increasing the diameter of Al NPs from 40 nm to 80 nm. In the direction that is greater than the critical angle, the transmittance of s-polarization is very small due to the strong absorption of Al NPs, while the transmittance spectrum of p-polarization can be observed obviously for the 80 nm Al NPs structure. For a ~284 nm AlGaN-based LED with surface plasmon (SP) coupling, although the luminous efficiency is significantly improved due to the improvement of the radiation recombination rate as compared with the conventional LED, the light extraction efficiency (LEE) is lower than 2.61% of the conventional LED without considering the lateral surface extraction and bottom reflection. The LEE is not greater than ~0.98% (~2.12%) for an SP coupling LED with 40 nm (80 nm) Al NPs. The lower LEE can be attributed to the strong absorption of Al NPs.


2021 ◽  
Vol 12 ◽  
Author(s):  
Sergey Mursalimov ◽  
Nobuhiko Ohno ◽  
Mami Matsumoto ◽  
Sergey Bayborodin ◽  
Elena Deineko

Serial block-face scanning electron microscopy (SBF-SEM) was used here to study tobacco male meiosis. Three-dimensional ultrastructural analyses revealed that intercellular nuclear migration (INM) occurs in 90–100% of tobacco meiocytes. At the very beginning of meiosis, every meiocyte connected with neighboring cells by more than 100 channels was capable of INM. At leptotene and zygotene, the nucleus in most tobacco meiocytes approached the cell wall and formed nuclear protuberances (NPs) that crossed the cell wall through the channels and extended into the cytoplasm of a neighboring cell. The separation of NPs from the migrating nuclei and micronuclei formation were not observed. In some cases, the NPs and nuclei of neighboring cells appeared apposed to each other, and the gap between their nuclear membranes became invisible. At pachytene, NPs retracted into their own cells. After that, the INM stopped. We consider INM a normal part of tobacco meiosis, but the reason for such behavior of nuclei is unclear. The results obtained by SBF-SEM suggest that there are still many unexplored features of plant meiosis hidden by limitations of common types of microscopy and that SBF-SEM can turn over a new leaf in plant meiosis research.


2019 ◽  
Vol 16 (160) ◽  
pp. 20190547 ◽  
Author(s):  
Babak N. Safa ◽  
John M. Peloquin ◽  
Jessica R. Natriello ◽  
Jeffrey L. Caplan ◽  
Dawn M. Elliott

Tendon's hierarchical structure allows for load transfer between its fibrillar elements at multiple length scales. Tendon microstructure is particularly important, because it includes the cells and their surrounding collagen fibrils, where mechanical interactions can have potentially important physiological and pathological contributions. However, the three-dimensional (3D) microstructure and the mechanisms of load transfer in that length scale are not known. It has been postulated that interfibrillar matrix shear or direct load transfer via the fusion/branching of small fibrils are responsible for load transfer, but the significance of these mechanisms is still unclear. Alternatively, the helical fibrils that occur at the microstructural scale in tendon may also mediate load transfer; however, these structures are not well studied due to the lack of a three-dimensional visualization of tendon microstructure. In this study, we used serial block-face scanning electron microscopy to investigate the 3D microstructure of fibrils in rat tail tendon. We found that tendon fibrils have a complex architecture with many helically wrapped fibrils. We studied the mechanical implications of these helical structures using finite-element modelling and found that frictional contact between helical fibrils can induce load transfer even in the absence of matrix bonding or fibril fusion/branching. This study is significant in that it provides a three-dimensional view of the tendon microstructure and suggests friction between helically wrapped fibrils as a mechanism for load transfer, which is an important aspect of tendon biomechanics.


2017 ◽  
Vol 114 (47) ◽  
pp. 12590-12595 ◽  
Author(s):  
Maridel A. Fredericksen ◽  
Yizhe Zhang ◽  
Missy L. Hazen ◽  
Raquel G. Loreto ◽  
Colleen A. Mangold ◽  
...  

Some microbes possess the ability to adaptively manipulate host behavior. To better understand how such microbial parasites control animal behavior, we examine the cell-level interactions between the species-specific fungal parasite Ophiocordyceps unilateralis sensu lato and its carpenter ant host (Camponotus castaneus) at a crucial moment in the parasite’s lifecycle: when the manipulated host fixes itself permanently to a substrate by its mandibles. The fungus is known to secrete tissue-specific metabolites and cause changes in host gene expression as well as atrophy in the mandible muscles of its ant host, but it is unknown how the fungus coordinates these effects to manipulate its host’s behavior. In this study, we combine techniques in serial block-face scanning-electron microscopy and deep-learning–based image segmentation algorithms to visualize the distribution, abundance, and interactions of this fungus inside the body of its manipulated host. Fungal cells were found throughout the host body but not in the brain, implying that behavioral control of the animal body by this microbe occurs peripherally. Additionally, fungal cells invaded host muscle fibers and joined together to form networks that encircled the muscles. These networks may represent a collective foraging behavior of this parasite, which may in turn facilitate host manipulation.


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