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Physical Review Letters Dec 2023A method for measuring helium atom diffraction with micron-scale spatial resolution is demonstrated in a scanning helium microscope (SHeM) and applied to study a...
A method for measuring helium atom diffraction with micron-scale spatial resolution is demonstrated in a scanning helium microscope (SHeM) and applied to study a micron-scale spot on the (100) plane of a lithium fluoride (LiF) crystal. The positions of the observed diffraction peaks provide an accurate measurement of the local lattice spacing, while a combination of close-coupled scattering calculations and Monte Carlo ray-tracing simulations reproduce the main variations in diffracted intensity. Subsequently, the diffraction results are used to enhance image contrast by measuring at different points in reciprocal space. The results open up the possibility for using helium microdiffraction to characterize the morphology of delicate or electron-sensitive materials on small scales. These include many fundamentally and technologically important samples which cannot be studied in conventional atom scattering instruments, such as small grain size exfoliated 2D materials, polycrystalline samples, and other surfaces that do not exhibit long-range order.
PubMed: 38134765
DOI: 10.1103/PhysRevLett.131.236202 -
Diseases of Aquatic Organisms Apr 2024A need exists for additional methods to examine cnidaria at the cellular level to aid our understanding of health, anatomy, and physiology of this important group of...
A need exists for additional methods to examine cnidaria at the cellular level to aid our understanding of health, anatomy, and physiology of this important group of organisms. This need is particularly acute given that disease is emerging as a major factor in declines of ecologically important functional groups such as corals. Here we describe a simple method to process cnidarian cells for microscopic examination using the model organism Exaiptasia. We show that this organism has at least 18 cell types or structures that can be readily distinguished based on defined morphological features. Some of these cells can be related back to anatomic features of the animal both at the light microscope and ultrastructural level. The cnidome of Exaiptasia may be more complex than what is currently understood. Moreover, cnidarian cells, including some types of cnidocytes, phagocytize cells other than endosymbionts. Finally, our findings shed light on morphologic complexity of cell-associated microbial aggregates and their intimate intracellular associations. The tools described here could be useful for other cnidaria.
Topics: Animals; Cnidaria; Cytology
PubMed: 38661136
DOI: 10.3354/dao03781 -
Biosensors & Bioelectronics Apr 2024Cell imaging technology is undoubtedly a powerful tool for studying single-cell heterogeneity due to its non-invasive and visual advantages. It covers microscope...
Cell imaging technology is undoubtedly a powerful tool for studying single-cell heterogeneity due to its non-invasive and visual advantages. It covers microscope hardware, software, and image analysis techniques, which are hindered by low throughput owing to abundant hands-on time and expertise. Herein, a cellular nucleus image-based smarter microscope system for single-cell analysis is reported to achieve high-throughput analysis and high-content detection of cells. By combining the hardware of an automatic fluorescence microscope and multi-object recognition/acquisition software, we have achieved more advanced process automation with the assistance of Robotic Process Automation (RPA), which realizes a high-throughput collection of single-cell images. Automated acquisition of single-cell images has benefits beyond ease and throughout and can lead to uniform standard and higher quality images. We further constructed a single-cell image database-based convolutional neural network (Efficient Convolutional Neural Network, E-CNN) exceeding 20618 single-cell nucleus images. Computational analysis of large and complex data sets enhances the content and efficiency of single-cell analysis with the assistance of Artificial Intelligence (AI), which breaks through the super-resolution microscope's hardware limitation, such as specialized light sources with specific wavelengths, advanced optical components, and high-performance graphics cards. Our system can identify single-cell nucleus images that cannot be artificially distinguished with an accuracy of 95.3%. Overall, we build an ordinary microscope into a high-throughput analysis and high-content smarter microscope system, making it a candidate tool for Imaging cytology.
Topics: Artificial Intelligence; Biosensing Techniques; Software; Image Processing, Computer-Assisted; Microscopy, Fluorescence; Single-Cell Analysis
PubMed: 38266616
DOI: 10.1016/j.bios.2024.116052 -
Cornea Dec 2023There are no defined diagnostic criteria and severity classification for Fuchs endothelial corneal dystrophy (FECD), which are required for objective standardized...
PURPOSE
There are no defined diagnostic criteria and severity classification for Fuchs endothelial corneal dystrophy (FECD), which are required for objective standardized assessments. Therefore, we performed a systematic literature review of the current diagnosis and severity classification of FECD.
METHODS
We searched the Ovid MEDLINE and Web of Science databases for studies published until January 13, 2021. We excluded review articles, conference abstracts, editorials, case reports with <5 patients, and letters.
RESULTS
Among 468 articles identified, we excluded 173 and 165 articles in the first and second screenings, respectively. Among the 130 included articles, 61 (47%) and 99 (76%) mentioned the diagnostic criteria for FECD and described its severity classification, respectively. Regarding diagnosis, slitlamp microscope alone was the most frequently used device in 31 (51%) of 61 articles. Regarding diagnostic findings, corneal guttae alone was the most common parameter [adopted in 23 articles (38%)]. Regarding severity classification, slitlamp microscopes were used in 88 articles (89%). The original or modified Krachmer grading scale was used in 77 articles (78%), followed by Adami's classification in six (6%). Specular microscopes or Scheimpflug tomography were used in four articles (4%) and anterior segment optical coherence tomography in one (1%).
CONCLUSIONS
FECD is globally diagnosed by the corneal guttae using slitlamp examination, and its severity is predominantly determined by the original or modified Krachmer grading scale. Objective severity grading using Scheimpflug or anterior segment optical coherence tomography can be applied in the future innovative therapies such as cell injection therapy or novel small molecules.
Topics: Humans; Fuchs' Endothelial Dystrophy; Tomography, Optical Coherence; Slit Lamp Microscopy; Endothelium, Corneal
PubMed: 37603692
DOI: 10.1097/ICO.0000000000003343 -
The Journal of Histochemistry and... Mar 2024Correlative microscopy is a sophisticated imaging technique that combines optical and electron microscopes, with the most common approach being the integration of light...
Correlative microscopy is a sophisticated imaging technique that combines optical and electron microscopes, with the most common approach being the integration of light microscopy and electron microscopy, known as correlative light and electron microscopy (CLEM). While CLEM provides a comprehensive view of biological samples, it presents a significant challenge in sample preparation due to the distinct processes involved in each technique. Striking a balance between these methods is crucial. Despite numerous approaches, achieving seamless imaging with CLEM remains a complex task. Exosomes, nanovesicles ranging from 30 to 150 nm in size, are enclosed by a lipid bilayer and released by various cell types. Visualizing exosomes poses difficulties due to their small size and minimal electric charge. However, imaging exosomes at high resolution offers a direct method to understand their morphology and functions. In this study, we evaluated exosome imaging with CLEM using a combination of confocal, transmission electron microscope, and scanning electron microscope (SEM). In addition, we conducted a comparative analysis of these two techniques, evaluating their suitability and efficiency in imaging nanoscale structures. In this study, we found that confocal-SEM correlation is more applicable for imaging exosomes. Moreover, we observed that exosomes were found in clusters in confocal-SEM correlation.
Topics: Microscopy, Fluorescence; Exosomes; Microscopy, Electron; Microscopy, Confocal; Microscopy, Electron, Scanning
PubMed: 38400717
DOI: 10.1369/00221554241233346 -
Microscopy (Oxford, England) Aug 2023Studies visualizing plant tissues and organs in three-dimension (3D) using micro-computed tomography (CT) published since approximately 2015 are reviewed. In this... (Review)
Review
Studies visualizing plant tissues and organs in three-dimension (3D) using micro-computed tomography (CT) published since approximately 2015 are reviewed. In this period, the number of publications in the field of plant sciences dealing with micro-CT has increased along with the development of high-performance lab-based micro-CT systems as well as the continuous development of cutting-edge technologies at synchrotron radiation facilities. The widespread use of commercially available lab-based micro-CT systems enabling phase-contrast imaging technique, which is suitable for the visualization of biological specimens composed of light elements, appears to have facilitated these studies. Unique features of the plant body, which are particularly utilized for the imaging of plant organs and tissues by micro-CT, are having functional air spaces and specialized cell walls, such as lignified ones. In this review, we briefly describe the basis of micro-CT technology first and then get down into details of its application in 3D visualization in plant sciences, which are categorized as follows: imaging of various organs, caryopses, seeds, other organs (reproductive organs, leaves, stems and petioles), various tissues (leaf venations, xylems, air-filled tissues, cell boundaries, cell walls), embolisms and root systems, hoping that wide users of microscopes and other imaging technologies will be interested also in micro-CT and obtain some hints for a deeper understanding of the structure of plant tissues and organs in 3D. Majority of the current morphological studies using micro-CT still appear to be at a qualitative level. Development of methodology for accurate 3D segmentation is needed for the transition of the studies from a qualitative level to a quantitative level in the future.
Topics: X-Ray Microtomography; Imaging, Three-Dimensional; Plants; Synchrotrons; Microscopy, Phase-Contrast
PubMed: 37098215
DOI: 10.1093/jmicro/dfad026 -
Journal of Microscopy May 2024When the first concrete was poured in 1949 for the Hungry Horse Dam (Montana, USA), pozzolan cements had already been used in several major North American dams,...
When the first concrete was poured in 1949 for the Hungry Horse Dam (Montana, USA), pozzolan cements had already been used in several major North American dams, including Grand Coulee on the Columbia River (diatomaceous earth explored but ultimately not used), Friant on the San Joaquin River and Altus on the North Fork Red River (pumicite) and Bonneville on the Columbia River and Davis on the Colorado River (calcined clay). But Hungry Horse Dam stands out as the first dam constructed using coal combustion fly ash. Utilising 2.4 million cubic metres of concrete, the dam is located on the South Fork Flathead River, one of the tributaries feeding one of the nation's major waterways, the Columbia River, and closely related to the adjacent Glacier National Park. In this respect, Hungry Horse is directly connected to two momentous periods in modern history - the massive adoption in the 1950s of coal as fuel for power plants, and the ongoing threats to fresh water supply and the rapid retreat of alpine glaciers due to global warming. Two concrete cores from this dam, one with fly ash and one without fly ash, are examined microscopically to explore the long-term suppression of alkali-aggregate reaction by fly ash. The core without fly ash exhibits clear evidence of alkali-aggregate reaction, manifested by sandstone coarse aggregate particles with darkened reaction rims. Sandstone coarse aggregate particles of the same lithology in the core with fly ash are without signs of alkali-aggregate reaction. A detailed examination of the darkened rims indicates that alkali-silica reaction products fill the narrow gaps between adjacent sand grains in the sandstone. This alkali-silica gel infilling allows for optical continuity between adjacent sand grains and is responsible for the classic darkened rim associated with the alkali-aggregate reaction.
PubMed: 37986607
DOI: 10.1111/jmi.13248 -
Journal of Korean Neurosurgical Society Apr 2024Microscopic microvascular decompression (MVD) has been considered to be a useful treatment modality for medically refractory hemifacial spasm (HFS) and trigeminal...
OBJECTIVE
Microscopic microvascular decompression (MVD) has been considered to be a useful treatment modality for medically refractory hemifacial spasm (HFS) and trigeminal neuralgia (TN). But, the advent of the endoscopic era has presented new possibilities to MVD surgery. While the microscope remains a valuable tool, the endoscope offers several advantages with comparable clinical outcomes. Thus, fully endoscopic MVD (E-MVD) could be a reasonable alternative to microscopic MVD. This paper explores the safety and efficacy of the fully E-MVD technique.
METHODS
A single-center retrospective study was conducted in 25 patients diagnosed with HFS between September 2019 and July 2023. All surgeries were performed by a single neurosurgeon using the fully E-MVD technique without any assistance of a microscope. The study reviewed intraoperative brainstem auditory evoked potentials and disappearance of the lateral spread response. Outcomes were assessed based on the patients' clinical status immediately after surgery and at their last follow-up. Complications, including facial palsy, hearing loss, ataxia, dysphagia, palsy of other cranial nerves, and cerebrospinal fluid (CSF) leakage, were also examined.
RESULTS
The most common offending artery was the anterior inferior cerebellar artery (AICA) in 15 cases (60.0%), followed by the posterior inferior cerebellar artery (PICA) in 8 cases (32.0%), vertebral artery (VA) in 1 case (4.0%), tandem lesions involving the AICA and VA in 1 case (4.0%). Ten patients (40.0%) had pre-operative facial palsy on the ipsilateral side, and 8 patients (32.0%) experienced delayed facial palsy on the ipsilateral side, from which they fully recovered by the last follow-up. The median operation time was 105 minutes. All patients were symptom free immediately after surgery and at the last follow-up. One patient experienced a permanent complication, such as high-frequency hearing loss, from which he partially recovered over time.
CONCLUSION
Fully E-MVD demonstrated similar clinical outcomes to microscopic MVD. It offered a similar complication rate, shorter operation time, and a panoramic view with a smaller craniectomy size. Although there is a learning curve associated with fully E-MVD, it presents a viable alternative in the endoscopic era.
PubMed: 38583999
DOI: 10.3340/jkns.2024.0003 -
Environmental Science and Pollution... Oct 2023Electrolytic manganese residue (EMR) is a solid waste that contains a significant amount of soluble manganese and ammonia nitrogen, which can pose risks to human health... (Review)
Review
Electrolytic manganese residue (EMR) is a solid waste that contains a significant amount of soluble manganese and ammonia nitrogen, which can pose risks to human health if improperly disposed of. This study aimed to prepare cementitious materials containing abundant ettringite crystals by mixing EMR with various proportions of granulated blast furnace slag (GBFS) and alkaline activators (CaO, Ca(OH), clinker, NaOH). The resulting cementitious material not only utilized a substantial amount of EMR but also exhibited comparable strength to ordinary Portland cement. The optimal ratios were determined through mechanical testing. Additionally, the leaching toxicity of cementitious materials was assessed using ICP-MS (inductively coupled plasma mass spectrometer) tests. The microscopic properties, hydration, and mechanism of heavy metal solidification in the cementitious materials were evaluated using XRD (X-ray diffraction), SEM (scanning electron microscope), EDS (energy-dispersive spectrometer), FTIR (Fourier transform infrared spectroscopy), and TG (thermogravimetric) techniques. The results showed that the optimal ratio for the cementitious materials was 60% EMR, 36% GBFS, and 4% Ca(OH). The hardened mortar exhibited compressive strengths of 34.43 MPa, 41.3 MPa, and 50.89 MPa at 3 days, 7 days, and 28 days, respectively, with an EMR utilization rate of 60%. The hydration products of EMR-based cementitious materials were C-(A)-S-H, AFt, and ferromanganese compounds, which contribute to the mechanical strength. The Mn and NH-N contents of raw EMR were 1220 and 149 mg/L, respectively. Nonetheless, the leaching of Mn and NH-N in the alkali-EMR-GBFS system was significantly below the limits set by the Chinese emission standard GB8978-1996. Within this system, C-(A)-S-H and AFt could physically adsorb and displace heavy metals, CaMn(SO)(SO)(OH)·24HO could replace Al ions with Mn ions, and ferromanganese compounds FeMn(PO)(OH)·(HO) and MnFeO could chemically precipitate Mn.
Topics: Humans; Manganese; Metals, Heavy; Iron; Electrolytes; Ions
PubMed: 37726634
DOI: 10.1007/s11356-023-29772-3 -
Asian Journal of Neurosurgery Dec 2023Many recent studies show that exoscopes are safe and effective alternatives to operating microscopes (OM). Developments of robotics and automation are present in...
Many recent studies show that exoscopes are safe and effective alternatives to operating microscopes (OM). Developments of robotics and automation are present in neurosurgery with the appearance of a newer device such as RoboticScope (RS) exoscope with a digital three-dimensional (3D) image and a head-mounted display. The body of the RS is connected to a six-axis robotic arm that contains two video cameras, and serves as stereovision. This robotic arm allows accurate 3D camera motions over the field of view, giving the user a great degree of freedom in viewpoint selection. The surgeons may specify the direction and speed of the robotic arm using simple head movements when the foot pedal is pressed. Since its development in 2020, the RS has occasionally been used in neurosurgery for a multitude of procedures. This study showcases vessel microanastomosis training on chicken legs using the RS. The aim of this study is to demonstrate the feasibility of the RS without a comparative analysis of the standard OM. The study was conducted in 2023 during a month-long trial period of the device at the Department of Neurosurgery of the Clinical Center of the University of Sarajevo. All procedures including RS-assisted anastomosis were performed by a neurosurgeon in anastomosis training (A.A.) supervised by a senior vascular neurosurgeon (E.B.). For the purpose of the study, we evaluated occlusion time in minutes, bypass patency with iodine, and overall satisfaction of the trainee in terms of light intensity, precision of automatic focus, mobility of the device, ergonomics, and convenience of the helmet. Ten RS-assisted microanastomoses were performed by interrupted suturing technique with 10.0 nylon thread. Bypass training included seven "end-to-side," two "end-to-end," and one "side-to-side" microanastomoses. The smallest vessel diameter was 1 mm. Occlusion time improved by training from 50 to 24 minutes, with contrast patency of the anastomoses in all cases without notable leakage of the contrast, except one case. Complete satisfaction of the trainee was achieved in 7 out of 10 cases. During this period, we also performed different RS-assisted surgeries including a single indirect bypass, convexity brain tumor resection, and microdiscectomies. RS provides a new concept for microanastomosis training as an alternative or adjunct to the standard microscope. We found a full-time hands-on microsuturing without the need for manual readjustment of the device as an advantage as well as instant depth at automatic zooming and precise transposition of the focus via head movements. However, it takes time to adapt and get used to the digital image. With the evolution of the device helmet's shortcomings, the RS could represent a cutting-edge method in vessel microanastomosis in the future. Nevertheless, this article represents one of the first written reports on microanastomosis training on an animal model with the above-mentioned device.
PubMed: 38161617
DOI: 10.1055/s-0043-1776794