The document discusses oscillatory motion and waves. It begins by introducing waves created by dropping a pebble in water, with the waves moving outward in expanding circles. It then discusses the main types of waves - mechanical and electromagnetic. Mechanical waves require a medium and examples include sound and water waves, while electromagnetic waves do not require a medium and include light, radio waves, and x-rays. The document goes on to define key variables of wave motion including wavelength, period, frequency, and amplitude. It also discusses the direction of particle displacement in transverse and longitudinal waves. Finally, it covers simple harmonic motion and how the acceleration, velocity, and force are related for objects undergoing SHM.
Introduction to oscillations and simple harmonic motionMichael Marty
Physics presentation about Simple Harmonic Motion of Hooke's Law springs and pendulums with derivation of formulas and connections to Uniform Circular Motion.
References include links to illustrative youtube clips and other powerpoints that contributed to this peresentation.
Introduction to oscillations and simple harmonic motionMichael Marty
Physics presentation about Simple Harmonic Motion of Hooke's Law springs and pendulums with derivation of formulas and connections to Uniform Circular Motion.
References include links to illustrative youtube clips and other powerpoints that contributed to this peresentation.
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.
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.
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.
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/
(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.
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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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 .
2. INTRODUCTION
Most of us experienced waves as children when we dropped a pebble into a pond.
At the point where the pebble hits the water’s surface, waves are created.
These waves move outward from the creation point in expanding circles until they
reach the shore.
3. INTRODUCTION
If you were to examine carefully the motion of a leaf floating on the disturbed
water, you would see that the leaf moves up, down, and sideways about its
original position but does not undergo any net displacement away from or toward
the point where the pebble hit the water.
The water molecules just beneath the leaf, as well as all the other water molecules
on the pond’s surface, behave in the same way. That is, the water wave moves
from the point of origin to the shore, but the water is not carried with it.
4. INTRODUCTION
The two main types being mechanical waves and electromagnetic waves. examples
of mechanical waves: sound waves, water waves.
In each case, some physical medium is being disturbed in our particular examples,
air molecules, water molecules.
Electromagnetic waves do not require a medium to propagate; some examples of
electromagnetic waves are visible light, radio waves, television signals, and x-rays.
5. BASIC VARIABLES OF WAVE MOTION
Imagine you are floating on a raft in a large lake. You slowly bob up and down as
waves move past you. As you look out over the lake, you may be able to see the
individual waves approaching.
The point at which the displacement of the water from its normal level is highest
is called the crest of the wave.
The distance from one crest to the next is called the wavelength (Greek letter
lambda).
More generally, the wavelength is the minimum distance between any two
identical points (such as the crests) on adjacent waves.
6. BASIC VARIABLES OF WAVE MOTION
If you count the number of seconds between the arrivals of two adjacent waves, you
are measuring the period T of the waves.
In general, the period is the time required for two identical points (such as the
crests) of adjacent waves to pass by a point.
The same information is more often given by the inverse of the period, which is called
the frequency f.
In general, the frequency of a periodic wave is the number of crests (or troughs, or
any other point on the wave) that pass a given point in a unit time interval.
The maximum displacement of a particle of the medium is called the amplitude A of
the wave.
7. DIRECTION OF PARTICLE DISPLACEMENT
Flick one end of a long rope that is under tension and has its opposite end fixed.
In this manner, a single wave bump (called a wave pulse) is formed and travels
along the rope with a definite speed.
This type of disturbance is called a traveling wave.
The rope is the medium through which the wave travels.
8. DIRECTION OF PARTICLE DISPLACEMENT
A traveling wave that causes the particles of the disturbed medium to move
perpendicular to the wave motion is called a transverse wave.
A traveling wave that causes the particles of the medium to move parallel to the
direction of wave motion is called a longitudinal wave.
Sound waves are another example of longitudinal waves.
The disturbance in a sound wave is a series of high-pressure and low-pressure
regions that travel through air or any other material medium.
9. DIRECTION OF PARTICLE DISPLACEMENT
Some waves in nature exhibit a combination of transverse and longitudinal
displacements.
Surface water waves are a good example. When a water wave travels on the
surface of deep water, water molecules at the surface move in nearly circular
paths.
10. DIRECTION OF PARTICLE DISPLACEMENT
The three-dimensional waves that travel out from the point under the Earth’s surface at
which an earthquake occurs are of both types—transverse and longitudinal.
The longitudinal waves are the faster of the two, traveling at speeds in the range of 7 to 8
km/s near the surface. These are called P waves (with “P” standing for primary because
they travel faster than the transverse waves and arrive at a seismograph first.
The slower transverse waves, called S waves (with “S” standing for secondary), travel
through the Earth at 4 to 5 km/s near the surface.
11. SIMPLE HARMONIC MOTION (SHM)
Any motion that repeats itself at regular intervals is called periodic motion or
harmonic motion.
For such motion the displacement x of the particle from the origin is given as a
function of time by
𝑥 𝑡 = 𝑥 𝑚 cos(𝜔𝑡 + 𝜑)
in which 𝑥 𝑚, 𝜔 and 𝜑 are constants. This motion is called simple harmonic
motion (SHM), a term that means the periodic motion is a sinusoidal function of
time.
12. SIMPLE HARMONIC MOTION (SHM)
The quantity 𝑥 𝑚, called the amplitude of the motion, is a positive constant whose
value depends on how the motion was started.
The subscript m stands for maximum because the amplitude is the magnitude of
the maximum displacement of the particle in either direction.
The cosine function varies between the limits ± 1; so the displacement x(t) varies
between the limits ± 𝑥 𝑚.
13. SIMPLE HARMONIC MOTION (SHM)
The time-varying quantity (𝜔𝑡 + 𝜑) is called the phase of the motion.
To interpret the constant , 𝜔 called the angular frequency of the motion, we first
note that the displacement x(t) must return to its initial value after one period T of
the motion; that is, x(t) must equal x(t + T) for all t. let put 𝜑 = 0
𝑥 𝑚 cos(𝜔𝑡) = 𝑥 𝑚 cos 𝜔(𝑡 + 𝑇)
The cosine function first repeats itself when its argument (the phase) has increased
by 2 𝜋 rad.
𝜔 𝑡 + 𝑇 = 𝜔𝑡 + 2 𝜋
𝜔𝑇 = 2 𝜋
𝜔=
2 𝜋
𝑇
= 2 𝜋𝑓
The SI unit of angular frequency is the radian per second.
14. VELOCITY AND ACCELERATION OF SHM
𝑣 𝑡 =
𝑑
𝑑𝑡
(𝑥 𝑡 ) =
𝑑
𝑑𝑡
𝑥 𝑚 cos(𝜔𝑡 + 𝜑)
𝑣 𝑡 = − 𝜔𝑥 𝑚 sin 𝜔𝑡 + 𝜑 → (𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑜𝑓 𝑆𝐻𝑀)
Now,
𝑎 𝑡 =
𝑑
𝑑𝑡
(𝑣 𝑡 ) =
𝑑
𝑑𝑡
(− 𝜔𝑥 𝑚 sin 𝜔𝑡 + 𝜑 )
𝑎 𝑡 = − 𝜔2
𝑥 𝑚 cos 𝜔𝑡 + 𝜑 → (𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑆𝐻𝑀)
𝑎 𝑡 = − 𝜔2 𝑥 𝑡
which is the hallmark of simple harmonic motion:
In SHM, the acceleration is proportional to the displacement but opposite in
sign, and the two quantities are related by the square of the angular frequency.
15. THE FORCE LAW FOR SIMPLE HARMONIC
MOTION (SHM)
How the acceleration of a particle varies with time, we can use Newton’s second
law to learn what force must act on the particle to give it that acceleration.
𝐹 = 𝑚𝑎 = − 𝑚𝜔2 𝑥
This result—a restoring force that is proportional to the displacement but opposite
in sign—is familiar. It is Hooke’s law,
𝐹 = −𝑘𝑥
for a spring, the spring constant here being
𝑘 = 𝑚𝜔2
Simple harmonic motion is the motion executed by a particle subject to a
force that is proportional to the displacement of the particle but opposite in
sign.
16. THE FORCE LAW FOR SIMPLE HARMONIC
MOTION (SHM)
The block spring system forms a linear simple harmonic oscillator where “linear” indicates
that F is proportional to x rather than to some other power of x.
The angular frequency 𝜔 of the simple harmonic motion of the block is related to the spring
constant k and the mass m of the block , which yields
𝑘 = 𝑚𝜔2
𝜔 =
𝑘
𝑚
From Relation
𝜔=
2 𝜋
𝑇
Or
𝑇 =
2 𝜋
𝜔
=2 𝜋
𝑚
𝑘
17. A mass on a horizontal spring m has a value of 0.80 kg and the spring constant k is 180 N m−1. At time t = 0
the mass is observed to be 0.04 m further from the wall than the equilibrium position and is moving away
from the wall with a velocity of 0.50 m s−1. Obtain an expression for the displacement of the mass in the form
x = A (cos ωt + φ), obtaining numerical values for A, ω and φ.
18.
19. NUMERICAL
A block whose mass m is 680 g is fastened to a spring whose spring constant k is 65 N/m.
The block is pulled a distance 𝑥 = 11𝑐𝑚 from its equilibrium position at 𝑥 = 0 on a
frictionless surface and released from rest at t = 0.
(a) What are the angular frequency, the frequency, and the period of the resulting motion?
(b) What is the amplitude of the oscillation?
(c) What is the maximum speed 𝑣 𝑚 of the oscillating block, and where is the block when it
has this speed?
(d) What is the magnitude 𝑎 𝑚 of the maximum acceleration of the block?
(e) What is the phase constant for the motion?
(f) What is the displacement function x(t) for the spring–block system?