Raman spectroscopy analyzes the scattering of electromagnetic radiation by molecules and materials. It can provide information about molecular vibrations, rotations, and bond characteristics. Raman spectra contain peaks corresponding to Stokes lines at lower frequencies and anti-Stokes lines at higher frequencies relative to the incident radiation. Rotational Raman spectroscopy of linear molecules follows selection rules of ΔJ = 0, ±2. Vibrational Raman spectroscopy requires a change in molecular polarizability during vibration.
A ppt compiled by Yaseen Aziz Wani pursuing M.Sc Chemistry at University of Kashmir, J&K, India and Naveed Bashir Dar, a student of electrical engg. at NIT Srinagar.
Warm regards to Munnazir Bashir also for providing us with refreshing tea while we were compiling ppt.
A ppt compiled by Yaseen Aziz Wani pursuing M.Sc Chemistry at University of Kashmir, J&K, India and Naveed Bashir Dar, a student of electrical engg. at NIT Srinagar.
Warm regards to Munnazir Bashir also for providing us with refreshing tea while we were compiling ppt.
NQR - DEFINITION - ELECTRIC FIELD GRADIENT - NUCLEAR QUADRUPOLE MOMENT - NUCLEAR QUADRUPOLE COUPLING CONSTANT - PRINCIPLE OF NQR - ENERGY OF INTERACTION - SELECTION RULE - FREQUENCY OF TRANSITION - APPLICATIONS
It contains the basic principle of Mossbauer Spectroscopy.
Recoil energy, Dopler shift.
The instrumentation of Mossbauer Spectroscopy.
Hyperfine interactions.
For UG students of All Engineering Branches (Mechanical Engg., Chemical Engg., Instrumentation Engg., Food Technology) and PG students of Chemistry, Physics, Biochemistry, Pharmacy
The link of the video lecture at YouTube is
https://www.youtube.com/watch?v=t3QDG8ZIX-8
Nmr nuclear magnetic resonance spectroscopyJoel Cornelio
Basics of NMR. Suitable for UG and PG courses.
Includes principle, instrumentation, solvents. chemical shift and factors affecting it. Some problems. resolving agents, coupling constant and much more
NQR - DEFINITION - ELECTRIC FIELD GRADIENT - NUCLEAR QUADRUPOLE MOMENT - NUCLEAR QUADRUPOLE COUPLING CONSTANT - PRINCIPLE OF NQR - ENERGY OF INTERACTION - SELECTION RULE - FREQUENCY OF TRANSITION - APPLICATIONS
It contains the basic principle of Mossbauer Spectroscopy.
Recoil energy, Dopler shift.
The instrumentation of Mossbauer Spectroscopy.
Hyperfine interactions.
For UG students of All Engineering Branches (Mechanical Engg., Chemical Engg., Instrumentation Engg., Food Technology) and PG students of Chemistry, Physics, Biochemistry, Pharmacy
The link of the video lecture at YouTube is
https://www.youtube.com/watch?v=t3QDG8ZIX-8
Nmr nuclear magnetic resonance spectroscopyJoel Cornelio
Basics of NMR. Suitable for UG and PG courses.
Includes principle, instrumentation, solvents. chemical shift and factors affecting it. Some problems. resolving agents, coupling constant and much more
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/
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.
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.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
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.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
3. Spectroscopy
Photons of the radiation bring information to us about the atom, molecule or
matter.
The different he analysis of the EM radiations emitted, absorbed or scattered
by atoms, molecules or matter
see between molecular and atomic spectroscopy: a molecule can make a
transition between its electronic, rotational and vibrational states.
The rotational and vibrational spectroscopy of a molecule can provide
information about the bond lengths, bond angles and bond strength in the
molecule
4. General features of spectroscopy
Emission spectrum: A molecule returns to a state of lower energy
E1 from an excited state of energy E2 by emitting a photon.
Absorption spectrum: A molecule is excited from a lower energy
state to a higher energy state by absorbing a photon as the
frequency of the incident radiation is swept over a range
c
EEh
1~
|| 21
is called the wavenumber of the
photon and gives the number of
complete wavelengths per centimeter.
It is in the unit of cm-1.
~
7. Other incident photons may collect energy from excited sample
molecules, emerging as higher frequency anti-Stokes lines.
Raman Spectroscopy
• Molecular energy levels are explored by examining the
frequencies present in radiation scattered by molecules.
• Most of the radiation is scattered without change of
frequency, giving the Rayleigh line.
• About 1 in 107 of the incident photons give up some
energy in collision with the sample molecules,
emerging with lower energy, giving lower frequency
Stokes lines.
8. Rotational Raman spectroscopy
Stokes lines: the scattered lines shifted to lower frequency than
the incident radiation (scat < inc)
Anti-Stokes lines: the scattered lines shifted to higher
frequency than the incident radiation (scat > inc)
Rayleigh lines: the scattered lines in the forward direction and
with the same frequency as the incident radiation (scat inc)
Rayleigh line
Visible or
ultraviolet
Lasers
9. Rotational Raman Spectra
Gross selection rule for rotational Raman transitions: molecule must
be anisotropically polarizable
An electric field applied to a
molecule results in its distortion,
and the distorted molecule acquires
a contribution to its dipole moment
(even if it is nonpolar initially). The
polarizability may be different when
the field is applied (a) parallel or (b)
perpendicular to the molecular axis
(or, in general, in different
directions relative to the molecule);
if that is so, then the molecule has
an anisotropic polarizability.
10. The distortion of a molecule in an electric field is determined
by its polarizability .
In addition to any permanent dipole moment a molecule may
have, the molecule acquires an induced dipole moment , if
the strength of the field is :
An atom is isotropically polarizable.
All linear molecules and diatomics (whether homonuclear or
heteronuclear) have anisotropic polarizabilities rotationally
Raman active
allows study of many molecules that are inaccessible to
microwave spectroscopy.
but some types of rotors both rotationally Raman &
microwave inactive
11. Gross selection rule
• The molecules must have anisotropic polarizability.
The polarizability of a molecule is a measure of the extent to which an
applied electric field can induce an electric dipole moment in addition to
any permanent dipole moment. The anisotropy of the polarizability is its
variation with the orientation of the molecule.
All spherical rotors, like tretrahedral (CH4), octahedral (SF6) and icosahedral
molecules (C60), are both rotationally and rotationally Raman inactive.
All homonuclear diatomic molecules and linear molecules are rotationally
inactive but rotationally Raman active.
>||
12. Specific rotational Raman selection rules:
Linear rotors: J = 0, 2
The distortion induced in
a molecule by an applied
electric field returns to its
initial value after a
rotation of only 180
(that is, twice a
revolution). This is the
origin of the J = 2
selection rule in
rotational Raman
spectroscopy.
13. Specific rotational Raman
selection rules
Linear rotors: J = 0, 2
Symmetric rotors: J = 0, 1, 2; K = 0
Asymmetric rotors:
For the latter, K is not a good quantum number,
so additional selection rules become too
complex.
A good quantum number is one which is
conserved in the presence of an external
interaction.
14. The rotational energy levels of a
linear rotor and the transitions
allowed by the J = 2 Raman
selection rules. The form of a
typical rotational Raman
spectrum is also shown.
Note: the J = 0 transitions do not
lead to a shift of the scattered
photon’s frequency in pure
rotational Raman Spectroscopy
contribute to unshifted Rayleigh
radiation in the forward direction
15. Stokes and anti-Stokes lines of rotational Raman spectrum
,..,,,JJB
JBhcEEE JJ
3210,)32(
~
2
)32(
~
2)( 2
For Stokes lines (J= +2)
• The rotational Raman spectrum consists of a series of lines at frequencies of
6 , 10 and 14 … , which are separated by 4 .
• We can use the value of B obtained from the rotational Raman spectrum to
estimate the bond length of a homonuclear diatomic molecule.
• The intensities of the Stokes lines are generally stronger than those of the
Anti-Stokes lines.
Stokes lines Anti-Stokes lines
For anti-Stokes lines (J= -2)
,..,JJB
JBhcEEE JJ
32,)12(
~
2
)12(
~
22
: Frequency shift relative to the incident radiation.
B
~
B
~
B
~
B
~
16. Rotational Raman spectrum of a diatomic
molecule with two identical nuclei of spin
½
For H2 molecules with nonzero nuclear spins,
the intensities of the odd-J lines are three
times more than those of the even-J lines.
Under rotation through 180°,
Wavefunctions with even J do not change sign.
Wavefunctions with odd J do change sign.
Nuclear statistics must be taken into
account whenever a rotation
interchanges equivalent nuclei.
rotnuctotal ψψψ
17. Vibrational Raman spectroscopy
• The incident photon leaves some of its energy in the vibrational modes of
the molecule it strikes (Stokes lines), or collects additional energy from a
vibration that has already been excited (Anti-Stokes lines).
• Gross selection rule: The molecular polarizability must change as the
molecule vibrates.
Both homonuclear and heteronuclear diatomic molecules are vibrationally
Raman active.
• Specific selection rules:
• The Stokes lines are more intense than the Anti-Stokes lines, because very
few molecules are in an excited vibrational state initially.
J = 0 or ±2, n = 1 )()()( tExxin
Induced dipole moment
18. Vibrational Raman spectra of polyatomic molecules
• The symmetric stretch of CO2 is Raman active, and the other are
Raman inactive.
• A general exclusion rule: If the molecule has a center of
inversion, then no modes can be both infrared and Raman active.
Gross selection rule: The vibrational normal mode is
accompanied by a change in the polarizability of the molecule.
19. Features of normal modes
A vibrational normal mode describes
a specific collective motion of atoms,
with each atom in a harmonic
oscillation of the same frequency. The
collective motion of a normal mode is
called a vibrational excitation.
In the harmonic approximation, all
normal modes of a molecule are
independent from one another. Each
normal mode behaves like an
independent harmonic oscillator. The
energies of the vibrational levels of
the i-th normal mode with frequency
i are
iin hnE i
2
1
Symmetric atretching and antisymmetric
stretching modes of CO2 molecule
Antisymmetric
stretching mode
Symmetric
Stretching mode
20. Vibration-rotation Raman spectrum of a linear rotor
Q branch: J = 0
S branch: J = +2
O branch: J = -2
JBBJ inO
~
4
~
2~~)(~
~~)(~
inQ J
JBBJ inS
~
4
~
6~~)(~