Transmission electron microscopy (TEM) uses a beam of electrons to image the internal structure of ultra-thin specimens. TEMs can achieve significantly higher resolutions than light microscopes due to the much shorter wavelength of electrons. Samples must be carefully prepared to be only a few hundred nanometers thick to be electron transparent. The electron beam is transmitted through the sample, interacting with it, and an image is formed from the transmitted electrons and magnified onto a viewing screen. TEM is widely used across various scientific fields including materials science, biology, and medicine.
Transmission electron microscope, high resolution tem and selected area elect...Nano Encryption
The transmission electron microscope is a very powerful tool for material science. A high energy beam of electrons is shone through a very thin sample, and the interactions between the electrons and the atoms can be used to observe features such as the crystal structure and features in the structure like dislocations and grain boundaries. Chemical analysis can also be performed. TEM can be used to study the growth of layers, their composition and defects in semiconductors. High resolution can be used to analyze the quality, shape, size and density of quantum wells, wires and dots.
Transmission electron microscope, high resolution tem and selected area elect...Nano Encryption
The transmission electron microscope is a very powerful tool for material science. A high energy beam of electrons is shone through a very thin sample, and the interactions between the electrons and the atoms can be used to observe features such as the crystal structure and features in the structure like dislocations and grain boundaries. Chemical analysis can also be performed. TEM can be used to study the growth of layers, their composition and defects in semiconductors. High resolution can be used to analyze the quality, shape, size and density of quantum wells, wires and dots.
SEM is a type of electron microscope designed for directly studying the surfaces of solid objects, that utilizes a beam of focused electron of relatively low energy as an electron probe that is scanned in a regular manner over the specimen.
Transmission electron microscopy (TEM)- by sivasangari Shanmugam. Transmission electron microscopy (TEM) is a technique used to observe the features of very small specimens.
SEM is a type of electron microscope designed for directly studying the surfaces of solid objects, that utilizes a beam of focused electron of relatively low energy as an electron probe that is scanned in a regular manner over the specimen.
Transmission electron microscopy (TEM)- by sivasangari Shanmugam. Transmission electron microscopy (TEM) is a technique used to observe the features of very small specimens.
Beam of electrons is transmitted through an ultra thin specimen,
An image is formed from the interaction of the electrons transmitted through the specimen,
The image is magnified and focused onto an imaging device, such as a fluorescent screen, on a layer of photographic film, or to be detected by a sensor such as a CCD camera
Wakhic People are Native Originated from Wakhan, presently living in Four Countries of our Time i.e. China, Pakistan, Afghanistan and Tajikistan. The Wakhic Language is on endanger list of Languages, therefor a message for the Day: When a Language dies, an identity dies, a cultural knowledge dies, a fruitful tree from the garden of world dies, so let's work together to safe guard the endangered languages.
Baig Ali
Acuerdos Acta 28 [12-Marzo-2015] del Núcleo de Investigación Didáctica y Tecnología Educativa de la Universidad Pedagógica Experimental Libertador - Instituto Pedagógico Rural "Gervasio Rubio", Rubio - Estado Táchira - Venezuela
Mechanical Engineer having 5+ years experience in Erection & Commissioning En...Qamar Ahmad
• Study of project and drawing as per planning sheet
• Work out of erection time and cost of project
• Site visit to check condition of the site and discuss with client regarding erection of equipment
• Allocate the workmen depending upon the erection schedule
• Allocate the requirement/facilities based upon the requirement.
• Specialized to do the modification at site as per the process requirement
• Knowledge of erection & fabrication drawings & PID drawings
• Provide solutions and fixed Crane or Hoist malfunctioning, modifications and performed replacements and /or new installation
• Assigned personnel and technical support teams to sites requiring erection
• Design and implemented special strategies related to erection procedures
• Inspection of assembled equipment, to ensure proper installation.
• Inspection of all operating parts to ensure proper operation within expected tolerances.
• Clearly and professionally interact with customer, regarding status of erection, on a daily basis
• Interact with internal and external project managers during field projects
• Preparing schedule and planning using MS Office and Word.
• Preparing of project documents such as weekly report, progress report, erection plan, precost and actual cost of projects, bar chart of projects etc
• Site visit for training and troubleshooting to client.
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is guided through an ultra thin specimen, interacting with the specimen as it passes through.An image is formed from the fundamental interaction of the electrons transmitted through the specimen; the image is magnified and focused onto an imaging device, such as a fluorescent screen, on a layer of photographic film, or to be observed by a sensor such as a CCD camera.
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
It is technique used to identify more clear picture of small organelles which are not able to distinguished by normal microscopy techniques. Its too expensive to perform that's why not used commonly.
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/
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
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.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
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.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
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.
1. Transmission Electron
Microscope
Transmission electron microscopy (TEM) is a
microscopy technique whereby a beam of electrons
is transmitted through an ultra thin specimen,
interacting with the specimen as it passes through.
An image is formed from the interaction of the
electrons transmitted through the specimen; the
image is magnified and focused onto an imaging
device, such as a fluorescent screen, on a layer of
photographic film, or to be detected by a sensor
such as a CCD camera. TEMs are capable of imaging
at a significantly higher resolution than light
microscopes .
2.
3. • The first TEM was built by Max Knoll and
Ernst Ruska in 1931, with this group
developing the first TEM with resolving
power greater than that of light in 1933 and
the first commercial TEM in 1939 .
4.
5. • TEM forms a major analysis method in a range of
scientific fields, in both physical and biological
sciences. It find application in cancer research,
virology, materials science as well as pollution
and semiconductor research.
• TEMs use electrons as "light source" and their
much lower wavelength makes it possible to get a
resolution a thousand times better than with a
light microscope .
6. • The wavelength of electrons is found by equating
the de Broglie equation to the kinetic energy of an
electron., in a TEM an electron's velocity
approaches the speed of light, c
• where, h is Planck's constant, m0 is the rest mass
of an electron and E is the energy of the
accelerated electron. Electrons are usually
generated in an electron microscope by a process
known as thermionic emission from a filament,
usually tungsten, in the same manner as a light
bulb, or alternatively by field electron emission
.The electrons are then accelerated by an electric
potential (measured in volts) and focused by
electrostatic and electromagnetic lenses onto the
sample. The transmitted beam contains
information about electron density, phase and
periodicity; this beam is used to form an image.
7.
8. METHODOLOGY
• A "light source" at the top of the microscope emits
the electrons that travel through vacuum in the
column of the microscope. Instead of glass lenses
focusing the light in the light microscope, the TEM
uses electromagnetic lenses to focus the
electrons into a very thin beam. The electron beam
then travels through the specimen you want to
study. Depending on the density of the material
present, some of the electrons are scattered and
disappear from the beam. At the bottom of the
microscope the unscattered electrons hit a
fluorescent screen, which gives rise to a parts
displayed in varied darkness according to their
density. The image can be studied directly by
operator or photographed with a camera.
9. SAMPLE PREPARATION
• Sample preparation in TEM can be a complex
procedure .The specimens are required to be at
most hundreds of nanometers thick. Preparation
of TEM specimens is specific to the material under
analysis and the desired information to obtain
from the specimen.
• Materials that have dimensions small enough to be
electron transparent, such as powders or
nanotubes, can be quickly prepared by the
deposition of a dilute sample containing the
specimen onto support grids or films .
10. • Biological specimens can be fixated using either a
negative staining material such as uranyl acetate
or by plastic embedding,or samples may be held
at liquid nitrogen temperatures after embedding in
vitreous ice. By passing samples over a glass or
diamond edge, small, thin sections can be readily
obtained using a semi-automated method or using
microtome. This method is used to obtain thin,
minimally deformed samples that allow for the
observation of tissue samples To prevent charge
build-up at the sample surface, tissue samples
need to be coated with a thin layer of conducting
material .
12. SAMPLE STAINING
• TEM samples of biological tissues can utilize high
atomic number stains to enhance contrast. The
stain absorbs electrons or scatters part of the
electron beam which otherwise is projected onto
the imaging system. Compounds of heavy metals
such as osmium, lead, or uranium may be used
prior to TEM observation to selectively deposit
electron dense atoms in or on the sample in
desired cellular or protein regions, requiring an
understanding of how heavy metals bind to
biological tissues.
13. • Mechanical milling: Polishing needs to be done to
a high quality, to ensure constant sample
thickness across the region of interest .
• Chemical etching :Certain samples may be
prepared by chemical etching, particularly metallic
specimens
• More recently focussed ion beam methods have
been used to prepare samples. FIB is a relatively
new technique to prepare thin samples for TEM
examination from larger specimens.
14. LIMITATIONS
• There are a number of drawbacks to the TEM
technique. Many materials require extensive
sample preparation to produce a sample thin
enough to be electron transparent, which makes
TEM analysis a relatively time consuming process
with a low throughput of samples. The structure of
the sample may also be changed during the
preparation process. Also the field of view is
relatively small, raising the possibility that the
region analysed may not be characteristic of the
whole sample. There is potential that the sample
may be damaged by the electron beam,
particularly in the case of biological materials.