Kinds of Friction
A moving object is affected by friction. However, the amount of friction may vary depending on the type of surface the object gets in contact with.
Rolling Friction
When an object rolls over a surface , rolling friction is produced. One of the most common examples of rolling friction is the movement of motor vehicle tires on the road , a process that generates heat and sound as by-products. Rolling friction is easier to overcome than sliding friction for similar materials. This type of friction is important to engineers who design certain products. For example, skates, skateboards, and bicycles need wheels that move freely.
Sliding Friction
Sliding friction occurs when two solid surfaces slide over each other. Sliding friction can be useful. For example, you can spread sand on an icy path to improve your footing. Ballet dancers apply a sticky powder to the soles of their ballet slippers so they won’t slip on the dance floor. And when you stop a bicycle with hand brakes, rubber pads slide against the tire surfaces, causing the wheels to slow and eventually stop. On the other hand, sliding friction is a problem if you fall off your bike and skin your knee!
Fluid Friction
Fluids, such as water, oil, or air, are materials that flow easily. Fluid friction occurs when a solid object moves through a fluid. Like rolling friction, fluid friction is easier to overcome than sliding friction.
Static Friction
The friction that acts on objects that are not moving is called static friction. Because of static friction, you must use extra force to start the motion of stationary objects. For example, think about what happens when you try to push a heavy desk across a floor. If you push on the desk with a force less than the force of static friction between the desk and the floor, the desk will not move. To make the desk move, you must exert a force greater than the force of static friction.
In this lesson, students will learn how gravity & friction can take affect on the simple things we do everyday of our lives. Learn the 3 main types of friction, & air resistance, plus a few examples. Finally, learn about terminal velocity & get a basic introduction to magnetic & electric forces with a slight distinction for buoyancy & density.
Summary
Definition
Friction is a catchall word that refers to any force that resists relative tangential motion (or intended motion).
"Relative tangential motion" is a fancy way to say "slipping" or "sliding".
Its direction is opposite the relative velocity (or intended velocity).
Types
Dry friction
The resistive force between solid surfaces in contact that resists their relative tangential motion.
"Friction" is often synonymous with "dry friction".
Viscous friction-
for more.......... go to this link :)
http://physics.info/friction/summary.shtml
In this lesson, students will learn how gravity & friction can take affect on the simple things we do everyday of our lives. Learn the 3 main types of friction, & air resistance, plus a few examples. Finally, learn about terminal velocity & get a basic introduction to magnetic & electric forces with a slight distinction for buoyancy & density.
Summary
Definition
Friction is a catchall word that refers to any force that resists relative tangential motion (or intended motion).
"Relative tangential motion" is a fancy way to say "slipping" or "sliding".
Its direction is opposite the relative velocity (or intended velocity).
Types
Dry friction
The resistive force between solid surfaces in contact that resists their relative tangential motion.
"Friction" is often synonymous with "dry friction".
Viscous friction-
for more.......... go to this link :)
http://physics.info/friction/summary.shtml
Best ppt on friction explaination, types of friction ,advantage & disadvantage of friction.effects of friction, methods of increacing and reducing friction,with example
Friction is a force that slows down moving objects or prevents stationary objects from moving .
Friction is a contact force .
Friction produces heat .
For example – A matchstick
Friction opposes the motion of an object
When one surface moves over another , these grooves and ridges get caught up with each other and slow down the motion . This causes friction .
Best ppt on friction explaination, types of friction ,advantage & disadvantage of friction.effects of friction, methods of increacing and reducing friction,with example
Friction is a force that slows down moving objects or prevents stationary objects from moving .
Friction is a contact force .
Friction produces heat .
For example – A matchstick
Friction opposes the motion of an object
When one surface moves over another , these grooves and ridges get caught up with each other and slow down the motion . This causes friction .
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
(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.
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.
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 increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
6. Friction positively affects the car
movement. For instance, without
friction, your car cannot move i.e. the
tires cannot push against the surface
(ground) to move the car and thereby
brakes cannot stop the car.
On the other hand, it can cause
problems too. Consider this example.
Friction between any engine parts
only increases the temperature and
thus causes engine parts to break
down; therefore, a coolant is added to
keep the temperature normal.
Friction Is Both Harmful And Helpful
7. As the sliding object slows down, most of the amount of
energy is transformed into heat. The friction converts
ordered energy into thermal energy or heat. For example,
in match lighting, the glass powder helps in creating
friction that’s needed for igniting flammable compounds at
the time of striking process.
Friction Often Heats Things Up
8. There’s A Strong Connection
Between Friction And Energy
Another interesting friction fact
that you might know is that
friction has a lot to do with
energy. If the two objects are
rubbing each other and one is
sliding down, it means the
objects are losing the energy.
The energy released is not at all
real and is rather kinetic energy.
9.
10.
11.
12.
13.
14.
15.
16. What is a Force?
•In science, a force is a push or a pull.
•All forces have two properties:
•Direction and Size
•A newton (N) is the unit that describes
the size of a force.
17. What Causes Friction?
• Friction is the force that opposes the motion between two
surfaces that touch.
• The surface of any object is rough.
• Even an object that feels smooth is covered with tiny hills
and valleys.
• The contact between the hills of valleys of two surfaces
causes them to stick, resulting in friction.
18. •The amount of friction depends on:
•Roughness of the surfaces
•Force pushing the surfaces together
What Causes Friction?
19. The Causes of Friction
In general, smooth surfaces produce less
friction than rough surfaces.
The strength of the force of friction depends
on two factors:
* How hard the surfaces push together
* The types of surfaces involved
https://www.youtube.com/watch?v=ybpFEB6Mt88
20. Friction also increases if
surfaces push hard against
each other.
If you rub your hands
together forcefully, there is
more friction than if you rub
your hands together lightly.
21. Friction acts in a direction
opposite to the direction of
the object’s motion.
Without friction, a moving
object might not stop until it
strikes another object.
22. • Kinetic friction occurs when force is applied to an
object and the object moves.
• Examples:
Sliding Friction: pushing an object across a surface
Rolling Friction: between wheels and a surface
Fluid Friction: opposes the motion of objects traveling
through a fluid (air or water)
Types of Friction
23. •Static friction occurs when force applied
to an object does not cause the object to
move.
Types of Friction
24. Sliding Friction
Sliding friction occurs when two solid surfaces
slide over each other.
Sliding friction can be useful.
For example, you can spread sand on an icy
path to improve your footing.
Ballet dancers apply a sticky powder to the
soles of their ballet slippers so they won’t slip
on the dance floor.
And when you stop a bicycle with hand brakes,
rubber pads slide against the tire surfaces,
causing the wheels to slow and eventually stop.
On the other hand, sliding friction is a problem
if you fall off your bike and skin your knee!
25. Rolling Friction
When an object rolls across a surface,
rolling friction occurs.
Rolling friction is easier to overcome
than sliding friction for similar
materials.
This type of friction is important to
engineers who design certain products.
For example, skates, skateboards, and
bicycles need wheels that move freely.
https://www.youtube.com/watch?v=HRe90ySP38U
26. • So engineers use ball bearings to
reduce the friction between the
wheels and the rest of the
product.
• These ball bearings are small,
smooth steel balls that reduce
friction by rolling between
moving parts.
27. Ball Bearings are a type of
rolling-element bearing that
uses balls to maintain the
separation between the moving
parts of the bearing.
28. Fluid Friction
Fluids, such as water, oil, or air,
are materials that flow easily.
Fluid friction occurs when a solid
object moves through a fluid.
Like rolling friction, fluid friction is
easier to overcome than sliding
friction.
https://www.youtube.com/watch?v=ZjlBlUvqnPo
29. This is why the parts of machines that
must slide over each other are often
bathed in oil or lubricants.
In this way, the solid parts move
through the fluid instead of sliding
against each other.
When you ride a bike, fluid friction
occurs between you and the air.
Cyclists often wear streamlined
helmets and specially designed
clothing to reduce fluid friction.
30. It is a substance,
such as oil or grease,
used for minimizing
friction, especially in
an engine or
component.
31. • To reduce the amount of friction, apply a lubricant between
two surfaces.
• Motor oil, wax, and grease are examples.
• Friction can also be reduced by rolling, rather than pushing,
an object.
Affecting Friction
32. •Friction increases as surfaces are made
rougher.
•Friction increases when the force
between two objects is increased.
Affecting Friction