Recent Advances in microscopy to view the ultrastructure of the cell
Scanning electron microscopes scan samples with an electron beam to produce images showing surface topography and composition. Cryo-electron tomography vitrifies biological materials and images them in a close-to-native state to acquire 3D information about macromolecular architecture and cellular states. Cellular tomography using cryo-ET can investigate processes like cell adhesion and mitosis as well as observe the cytoskeleton. Phase plate technology provides increased image contrast, allowing observation of thicker cell specimens in situ. Future improvements may allow routine subnanometer resolution cryo-ET observation of cellular features in their native environments.
Electron microscope, principle and applicationKAUSHAL SAHU
Introduction
History
Resolution &Magnification of
Electron microscope
Types of electron microscope
1) Transmission electron microscope (TEM)
- Structural parts of TEM
- Principle & Working of TEM
- Sample preparation for TEM
- Advantages & disadvantages of TEM
Scanning electron microscope (SEM)
- Structural parts of SEM
- Principle & Working of SEM
- Sample preparation for SEM
- Advantages & disadvantages of SEM
3) Scanning transmission electron microscope (STEM)
Applications of electron microscope
Conclusion
References
Electron microscope, principle and applicationKAUSHAL SAHU
Introduction
History
Resolution &Magnification of
Electron microscope
Types of electron microscope
1) Transmission electron microscope (TEM)
- Structural parts of TEM
- Principle & Working of TEM
- Sample preparation for TEM
- Advantages & disadvantages of TEM
Scanning electron microscope (SEM)
- Structural parts of SEM
- Principle & Working of SEM
- Sample preparation for SEM
- Advantages & disadvantages of SEM
3) Scanning transmission electron microscope (STEM)
Applications of electron microscope
Conclusion
References
slide gives detail about scanning electron microscope
Introduction to electron Microscope
Principle of SEM
Characteristics that can be viewed on SEM
Comparison OM V/S SEM
Components of SEM
SEM Sample preparation
Working SEM
Applications
Limitations
References
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Comparative structure of adrenal gland in vertebrates
Recent Advances in microscopy
1. Recent Advances in microscopy to view
the ultrastructure of the cell
Presented By
Divya S- I Ph.D (GPB)
2019608004
2. Scanning electron microscope
• A SEM is a type of electron microscope that images a sample by
scanning it with a by a high energy beam of electrons in a raster scan
pattern
• The electrons interact with the atoms that make up the sample
producing the signals that contain the information about the samples
surface topography, composition and other properties such as
electrical conductivity
3.
4.
5.
6.
7.
8.
9.
10.
11.
12. Cryo-electron tomography (cryo-ET)
• Electron microscopy (EM) has been pivotal in providing information
about cellular ultrastructure, as well as macromolecular organization
• Biological materials can be physically fixed by vitrification and imaged
with cryo-electron tomography (cryo-ET) in a close-to-native
condition
• Using this technique, one can acquire three-dimensional (3D)
information about the macromolecular architecture of cells, depict
unique cellular states and reconstruct molecular networks
13.
14. Cellular tomography
• Cellular processes, such as cell adhesion and mitosis, can be
investigated by cryo-ET. This approach can also be used to observe
the cytoskeleton (Kürner et al., 2004; Medalia et al., 2002, 2007).
• Early studies of the actin cytoskeleton were mostly focused on
morphological observations within the EM data.
• With the recent advances in cryo-ET, we can now evaluate some
filament properties within cells and even detect the helical pitch of
individual actin filaments . This makes it possible to determine the
polarity of each actin filament within the cytoskeletal network.
15.
16. Cellular tomography performed with phase
plates
• EM is mainly limited by how far electrons can penetrate through the biological sample,
restricting the thickness of the specimen to be examined to less than 1 μm.
• The newly available phase plate technology for EM provides increased image contrast and
therefore, makes it easier to identify fine cellular components within thicker specimens in
situ (Dai et al., 2013, 2014).
• Phase plates are typically positioned in the back focal plane of the objective lens of the EM
and shift the phase of the scattered electron beam such that low-frequency information is
amplified.
• This is the information that contributes to image contrast, and higher contrast makes it
possible to detect structural features within the data and, therefore, allows for the direct
observation and analysis of the internal 3D structure of cells .
17. Phase plate image of neurons
E- A slice of a tomogram acquired with a phase plate showing an intracisternal filament
bundle within the cisternae of the trans-Golgi (yellow arrow) and a nearby coated bud.
An acidocalcisome containing a dense aggregate of polyphosphate filaments is labeled with
‘ac’. Scale bar is 100 nm
F- Segmentation of the cisterna in E, with the Golgi membrane in dark orange, the coated
bud in yellow and the filament bundle in blue.
18. Future of Cryo- ET
• Cryo-ET is establishing itself as an invaluable technique for structural
cellular biology. A big milestone for cryo-ET will be to routinely reach
subnanometer resolution.
• The future of cryo-ET lies in the routine observation of cellular
features of interest within their native environment, in combination
with other upcoming structural techniques such as CLEM(Correlative
Light Electron Microscopy) and FIB (Focused Ion Beam).
