Presentation is based on Nuclear Magnetic Resonance Spectroscopy technique. It is well explained in concised form. Easy to understand, good fonts and attractive presentation.
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
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy, is a spectroscopic technique to observe local magnetic fields around atomic nuclei.
NMR, principle and instrumentation by kk sahu sirKAUSHAL SAHU
Introduction
History
Principle
Assembly
Solvents
Chemical shift
Factors affecting chemical shift
2D NMR
NOE effect
NOESY
COSY
Application
Conclusion
References
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
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy, is a spectroscopic technique to observe local magnetic fields around atomic nuclei.
NMR, principle and instrumentation by kk sahu sirKAUSHAL SAHU
Introduction
History
Principle
Assembly
Solvents
Chemical shift
Factors affecting chemical shift
2D NMR
NOE effect
NOESY
COSY
Application
Conclusion
References
NMR Spectroscopy is a powerful technique that can provide detailed information on the topology, dynamics and three-dimensional structure of molecules in solution and the solid state
NMR SPECTROSCOPY ,Relaxation,longitudinal / spin- spin relaxation,transverse / spin- spin relaxation,Shielding of proton ,Deshielding of proton,CHEMICAL SHIFT,Factors Influencing Chemical Shift,Inductive effect, Vander Waal’s deshielding,Anisotropic effect (space effect),Hydrogen bonding
,SPLITTING OF THE SIGNALS,COUPLING CONSTANT,NMR SIGNAL IN VARIOUS COMPOUND
more chemistry contents are available
1. pdf file on Termmate: https://www.termmate.com/rabia.aziz
2. YouTube: https://www.youtube.com/channel/UCKxWnNdskGHnZFS0h1QRTEA
3. Facebook: https://web.facebook.com/Chemist.Rabia.Aziz/
4. Blogger: https://chemistry-academy.blogspot.com/
BS-III
NQR - DEFINITION - ELECTRIC FIELD GRADIENT - NUCLEAR QUADRUPOLE MOMENT - NUCLEAR QUADRUPOLE COUPLING CONSTANT - PRINCIPLE OF NQR - ENERGY OF INTERACTION - SELECTION RULE - FREQUENCY OF TRANSITION - APPLICATIONS
NMR Spectroscopy is a powerful technique that can provide detailed information on the topology, dynamics and three-dimensional structure of molecules in solution and the solid state
NMR SPECTROSCOPY ,Relaxation,longitudinal / spin- spin relaxation,transverse / spin- spin relaxation,Shielding of proton ,Deshielding of proton,CHEMICAL SHIFT,Factors Influencing Chemical Shift,Inductive effect, Vander Waal’s deshielding,Anisotropic effect (space effect),Hydrogen bonding
,SPLITTING OF THE SIGNALS,COUPLING CONSTANT,NMR SIGNAL IN VARIOUS COMPOUND
more chemistry contents are available
1. pdf file on Termmate: https://www.termmate.com/rabia.aziz
2. YouTube: https://www.youtube.com/channel/UCKxWnNdskGHnZFS0h1QRTEA
3. Facebook: https://web.facebook.com/Chemist.Rabia.Aziz/
4. Blogger: https://chemistry-academy.blogspot.com/
BS-III
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 would be use full to All Needy People. It involve information about NMR Spectroscopy ( a spectroscopic techniques), factors influencing , proton NMR and their applications of NMR as well as Nuclear magnetic imaging.
Nuclear magnetic resonance (NMR) GULSHAN.pptxGULSHAN KUMAR
Nuclear Magnetic Resonance (NMR) Spectroscopy is a non-destructive analytical technique that is used to probe the nature and characteristics of molecular structure.
CHEMICAL SHIFT AND ITS FACTOR EFFECTS, COUPLING CONSTANT, FIRST ORDER TO NON FIRST ORDER, SPIN SYSTEMS, CHEMICAL EQUIVALENCE AND NON EQUIVALENCE, TIRUMALA SANTHOSHKUMAR S
NMR - Nuclear magnetic resonance (NMR).pptxmuskaangandhi1
Nuclear magnetic resonance (NMR) spectroscopy is the study of molecules by recording the interaction of radiofrequency (Rf) electromagnetic radiations with the nuclei of molecules placed in a strong magnetic field.
It is concerned with absorption of certain amount of energy
by spinning nuclei in a magnetic field when irradiated with
radiofrequency radiation (RFR) of equivalent energy.
NMR gives the information about the number and configuration of
magnetically active atoms, like positions of different types
of Hydrogen over the C- skeleton of an organic molecule.
Absorption of RFR occurs when the nucleus undergoes
transition from one alignment in the applied magnetic field
to the opposite alignment, i.e. from parallel (ground state)
orientation to anti-parallel (excited state) orientation.
When the frequency of the oscillating electric field of the
incoming RFR just matches the frequency of the electric field
generated by the precising nucleus, then the 2 fields can
couple, and the energy can be transferred from the
incoming radiation to the nucleus, thus causing a spin change
(clock-wise to anti-clock-wise).
This condition is called "resonance", and the nucleus is said to
have resonance with the incoming electromagnetic wave
(RFR).
In NMR technique, the frequency of the RFR is kept constant
(60MHz) and the strength of magnetic field is varied.
At certain value of the applied field strength, depending
upon the nature of proton or nucleus, the energy required to
flip the proton matches the energy of radiation.
As a result, absorption takes place and a signal is observed
in the spectrum. Such a signal or peak is called an NMR
Spectrum.
NMR spectrum is graphical plot of relative intensity
(Y axis) and the δ value (x axis).
The nucleus of a hydrogen atom (proton) behaves as a spinning bar magnet because it possesses both electric and magnetic spin.
Like any other spinning charged body, the nucleus of hydrogen atom also generates a magnetic field.
Nuclear magnetic resonance Involves the interaction between an oscillating magnetic field of electromagnetic radiation and the magnetic energy of the hydrogen nucleus or some other type of nuclei when these are placed in an external static magnetic field.
The sample absorbs electromagnetic radiations in radio wave region at different frequencies since absorption depends upon the type of protons or certain nuclei contained in the sample)
Consider a spinning top. It also performs a slower waltz like motion,
in which the spinning axis of the top moves slowly around
the vertical.
This is processional motion & the top is said to be processing around the vertical axis of earth's gravitational field.
The precession arises from the interaction of spin with earth's gravity acting vertically downwards.
It is called Gyroscopic motion.
Proton will be showing processional motion due to interaction of Spin &
Gravitational force of Earth
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.
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 .
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.
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.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
2. WHAT IS NMR?
• Nuclear Magnetic Resonance
Spectroscopy commonly referred to as
NMR, is a technique which exploits
the magnetic properties of certain
nuclei to study physical, chemical and
biological properties of matter.
3. HISTORY
• The Purcell group at Harvard University
and the Bloch group at Stanford University
independently developed NMR
spectroscopy in the late1940s and early
1950s.
• Edward Mills Purcell and Felix Bloch
shared the 1952 Nobel Prize of Physics for
their discoveries.
Edward Mills Purcell
Felix Bloch
4. TYPES
• Most commonly they are of two types:
1H NMR - It is also called PMR. It is used to
determine the type and number of H atoms and
spatial arrangement of them in a molecule.
13C NMR – It is also called CMR. It is used to
determine the type and number of C atoms and
spatial arrangement of them in a molecule.
5. PRINCIPLE
• NUCLEAR SPIN – It is total angular momentum of
nucleus and represented by I.
The principle behind NMR is that many nuclei have spin and
all nuclei are electrically charged.
If the number of neutrons plus the number of protons is odd,
then the nucleus has a half integer spin i.e. ½, 3/2, 5/2.
If the number of neutrons and number of protons both are odd
then the nucleus has an integer spin i.e. 1, 2, 3.
And if both the neutrons and protons are even the nucleus has
NO spin states.
A nucleus of spin I will have 2I+1 possible orientations.
7. WHEN EXTERNAL MAGNETIC FIELD IS
APPLIED FOLLOWING THINGS HAPPEN:
When placed in an external
field, spinning proton act like
bar magnets
The magnetic fields of the spinning
nuclei will align either with the
external field or against the field
8. • NUCLEAR SPIN RESONANCE The magnetic nuclei under the influence of
external magnetic field can absorb and emit Electromagnetic Radiations.
• The nuclear spin aligned with the magnetic field has lower energy which is
called Alpha state and nuclear spin aligned opposite to magnetic field has
higher energy which is called Beta state.
• A photon with right amount of energy can be absorbed and cause the spinning
proton to flip.
• Energy Difference between two state is directly proportional to magnetic field
applied.
ν = 2μ · B0 · sin θ/h
9. • LARMOR FREQUENCY – Spinning Particle
wobbles about the external magnetic field axis
at an angular frequency known as LARMOR
FREQUENCY.(ω).
• The nucleus undergo transition from lower to
higher state when the resonance state is
achieved i.e. oscillating magnetic field
associated with electromagnetic radiations is at
right angle to applied magnetic field and
Larmor frequency is equal to frequency of
oscillating magnetic field. ω = 2π · ν.
• This requirement for the resonance condition
explains the inclusion of the word ‘resonance’
in ‘nuclear magnetic resonance’.
10. SHIELDING AND DESHIELDING OF PROTON
• Magnetic field strength must
be increased for a shielded
proton to flip at the same
frequency.
• Depending on their chemical
environment, protons in a
molecule are shielded by
different amounts.
11. CHEMICAL SHIFT
• The shift in the positions of NMR absorption
which arise due to shielding and deshielding
of protons by the electrons is called chemical
shift (delta δ).
• To study chemical shift, the signal for Tetra
methyl Silane is taken as reference because of
low electronegativity of silicon. It is measured
in ppm.
• δ = νS − νRef/νRef × 106
13. PREPARATION OF SAMPLE
• FOR SAMPLE PREPARATION SUBSTANCE FREE
OF PROTON SHOULD BE USED SO THAT IT DOES
NOT ABORPTION OF ITS OWN.
• AND SUBSTANCE ATLEAST 10% SOLUBLE IN IT.
• FOLLOWING SOLVENTS ARE USED:
• CCl4
• CS2
• CDCl3
14. NMR SPECTRA/SIGNALS
• The number of signals shows how many
different kinds of protons are present.
• The location of the signals show how
shielded or deshielded the proton is
• The intensity of the signal shows the
number of proton of that type.
• Signal splitting shows the number of
protons on adjacent atoms.
