Dark matter is invisible matter that accounts for approximately 27% of the mass-energy in the universe. Although it cannot be directly observed, astronomers deduce its existence through its gravitational effects, such as the anomalous rotation curves of galaxies. Dark matter is classified as cold, warm, or hot depending on the size of protogalaxies, and may consist of either baryonic matter like protons and neutrons or nonbaryonic particles like axions. It plays a prominent role in science fiction works but descriptions are often inconsistent with scientific understanding.
How the concept was introduced by the astrophycists and examples that provide the base for the existence of dark matter. Basic introduction to types of dark matter according to standard cosmological theory.
How the concept was introduced by the astrophycists and examples that provide the base for the existence of dark matter. Basic introduction to types of dark matter according to standard cosmological theory.
This PowerPoint is one small part of the Matter, Energy, and the Environment Unit from www.sciencepowerpoint.com. This unit consists of a five part 3,500+ slide PowerPoint roadmap, 12 page bundled homework package, modified homework, detailed answer keys, 20 pages of unit notes for students who may require assistance, follow along worksheets, and many review games. The homework and lesson notes chronologically follow the PowerPoint slideshow. The answer keys and unit notes are great for support professionals. The activities and discussion questions in the slideshow are meaningful. The PowerPoint includes built-in instructions, visuals, and review questions. Also included are critical class notes (color coded red), project ideas, video links, and review games. This unit also includes four PowerPoint review games (110+ slides each with Answers), 38+ video links, lab handouts, activity sheets, rubrics, materials list, templates, guides, and much more. Also included is a 190 slide first day of school PowerPoint presentation.
Areas of Focus: Matter, Dark Matter, Elements and Compounds, States of Matter, Solids, Liquids, Gases, Plasma, Law Conservation of Matter, Physical Change, Chemical Change, Gas Laws, Charles Law, Avogadro's Law, Ideal Gas Law, Pascal's Law, Archimedes Principle, Buoyancy, Seven Forms of Energy, Nuclear Energy, Electromagnet Spectrum, Waves / Wavelengths, Light (Visible Light), Refraction, Diffraction, Lens, Convex / Concave, Radiation, Electricity, Lightning, Static Electricity, Magnetism, Coulomb's Law, Conductors, Insulators, Semi-conductors, AC and DC current, Amps, Watts, Resistance, Magnetism, Faraday's Law, Compass, Relativity, Einstein, and E=MC2, Energy, First Law of Thermodynamics, Second Law of Thermodynamics-Third Law of Thermodynamics, Industrial Processes, Environmental Studies, The 4 R's, Sustainability, Human Population Growth, Carrying Capacity, Green Design, Renewable Forms of Energy (The 11th Hour)
This unit aligns with the Next Generation Science Standards and with Common Core Standards for ELA and Literacy for Science and Technical Subjects. See preview for more information
If you have any questions please feel free to contact me. Thanks again and best wishes. Sincerely, Ryan Murphy M.Ed www.sciencepowerpoint@gmail.com
Teaching Duration = 4+ Weeks
Slides from my presentation at the Joint CoEPP-CAASTRO Workshop (http://www.caastro.org/event/2013/coepp), 28 February 2013. Brief overview of the evidence for dark matter in the Universe, plus discussion of challenges, hints of possible signals, and some references for further reading.
The presentation time-slot was 30 minutes + 20 minutes discussion.
"Black holes are where God divided by zero" - Albert Einstein
Black hole – A region in the space where the gravitational pull is so strong that neither substance nor light can leave this area.
Contents
The Big Bang Theory
The Big Bang Phase
Expanding Universe
Testing Big Bang Model
Dark matter & Dark energy
Evidence of dark matter
After time period of Big Bang
Life cycle of star
This PowerPoint is one small part of the Matter, Energy, and the Environment Unit from www.sciencepowerpoint.com. This unit consists of a five part 3,500+ slide PowerPoint roadmap, 12 page bundled homework package, modified homework, detailed answer keys, 20 pages of unit notes for students who may require assistance, follow along worksheets, and many review games. The homework and lesson notes chronologically follow the PowerPoint slideshow. The answer keys and unit notes are great for support professionals. The activities and discussion questions in the slideshow are meaningful. The PowerPoint includes built-in instructions, visuals, and review questions. Also included are critical class notes (color coded red), project ideas, video links, and review games. This unit also includes four PowerPoint review games (110+ slides each with Answers), 38+ video links, lab handouts, activity sheets, rubrics, materials list, templates, guides, and much more. Also included is a 190 slide first day of school PowerPoint presentation.
Areas of Focus: Matter, Dark Matter, Elements and Compounds, States of Matter, Solids, Liquids, Gases, Plasma, Law Conservation of Matter, Physical Change, Chemical Change, Gas Laws, Charles Law, Avogadro's Law, Ideal Gas Law, Pascal's Law, Archimedes Principle, Buoyancy, Seven Forms of Energy, Nuclear Energy, Electromagnet Spectrum, Waves / Wavelengths, Light (Visible Light), Refraction, Diffraction, Lens, Convex / Concave, Radiation, Electricity, Lightning, Static Electricity, Magnetism, Coulomb's Law, Conductors, Insulators, Semi-conductors, AC and DC current, Amps, Watts, Resistance, Magnetism, Faraday's Law, Compass, Relativity, Einstein, and E=MC2, Energy, First Law of Thermodynamics, Second Law of Thermodynamics-Third Law of Thermodynamics, Industrial Processes, Environmental Studies, The 4 R's, Sustainability, Human Population Growth, Carrying Capacity, Green Design, Renewable Forms of Energy (The 11th Hour)
This unit aligns with the Next Generation Science Standards and with Common Core Standards for ELA and Literacy for Science and Technical Subjects. See preview for more information
If you have any questions please feel free to contact me. Thanks again and best wishes. Sincerely, Ryan Murphy M.Ed www.sciencepowerpoint@gmail.com
Teaching Duration = 4+ Weeks
Slides from my presentation at the Joint CoEPP-CAASTRO Workshop (http://www.caastro.org/event/2013/coepp), 28 February 2013. Brief overview of the evidence for dark matter in the Universe, plus discussion of challenges, hints of possible signals, and some references for further reading.
The presentation time-slot was 30 minutes + 20 minutes discussion.
"Black holes are where God divided by zero" - Albert Einstein
Black hole – A region in the space where the gravitational pull is so strong that neither substance nor light can leave this area.
Contents
The Big Bang Theory
The Big Bang Phase
Expanding Universe
Testing Big Bang Model
Dark matter & Dark energy
Evidence of dark matter
After time period of Big Bang
Life cycle of star
radioactivity is the act of emitting radiation spontaneously. This is done by an atomic nucleus that, for some reason, is unstable; it "wants" to give up some energy in order to shift to a more stable configuration.
Atoms, quanta,and qubits: Atomism in quantum mechanics and informationVasil Penchev
The original conception of atomism suggests “atoms”, which cannot be divided more into composing parts. However, the name “atom” in physics is reserved for entities, which can be divided into electrons, protons, neutrons and other “elementary particles”, some of which are in turn compounded by other, “more elementary” ones. Instead of this, quantum mechanics is grounded on the actually indivisible quanta of action limited by the fundamental Planck constant. It resolves the problem of how both discrete and continuous (even smooth) to be described uniformly and invariantly in thus. Quantum mechanics can be interpreted in terms of quantum information. Qubit is the indivisible unit (“atom”) of quantum information. The imagery of atomism in modern physics moves from atoms of matter (or energy) via “atoms” (quanta) of action to “atoms” (qubits) of quantum information. This is a conceptual shift in the cognition of reality to terms of information, choice, and time.
The evolution of radiation treatment planning and delivery, with innovative techniques (3DCRT, IMRT, IGRT, IGBT), particle therapy allowing for better definition of target and sensitive structure volumes and more precise quantification of dose, has introduced more complexity into the evaluation of radiation effects on OARs.
In this we explained;
Radiographic methods:
Introduction to electromagnetic waves and radioactivity, various decays, Attenuation ofelectromagnetic
radiations, Photo electric effect, Rayleigh’s scattering (coherent scattering),Compton’s scattering
(Incoherent scattering), Pair production, Beam geometry and Scatteringfactor.
X-ray radiography: principle, equipment & methodology, applications, types of radiations
andlimitations. γ-ray radiography – principle, equipment., source of radioactive materials &technique,
advantages of γ-ray radiography over X-ray radiography Precautions against radiationhazards.
origin of quantum physics -
Inadequacy of classical mechanics and birth of QUANTUM PHYSICS
ref: Quantum mechanics: concepts and applications, N. Zettili
X-ray diffraction, basic principle, instruments, Bragg's law, diffraction and...Quiad-i-Azam university
X-RAY Diffraction
1.Introduction
2.What is X-Ray?
3.Basic principle
4.Instrumentation
5.Bragg’s Law and X-Ray
6.Diffraction
7.Applications
INTRODUCTION:
X-rays are electromagnetic waves having wavelength in range of 0.1-100Å.
X-rays used in diffraction techniques have typical wavelength of 0.5-1.8Å.
X-rays were discovered by Wilhelm Roentgen who called them X-rays and it is also called as Roentgen rays.
BASIC PRINCIPLES:
In an atom, the electrons are arranged in layers or shells, like
K-shell
L-shell
M-shell
N-shell.
When the atom is bombarded with an electron, eject one of the electron from the inner shell.
The electrons migrate from the outer shell to the inner shell to fill the gap with higher energy.
A quantum of radiation (X-rays) is emitted corresponding to this transition, time scale is approximately 10-12-10-14 sec.
Emitted radiation is called X-rays.
X-RAY DIFFRACTION PRINCIPLE:
X-ray diffraction is based on constructive interference of monochromatic X-ray and a crystalline sample.
These rays are generated by a cathode ray tube, filtered to produce monochromatic radiation, collimated to concentrate and directed towards the sample.
The interaction of incident rays with the sample produces constructive interference when conditions satisfy Bragg’s law.
INSTRUMENTATION:
1.X-ray tube
2.Collimator
3.Monochromator
4.Filter
5.Crystalmonochromator
6.Detectors
APPLICATION OF X-RAY DIFFRACTION:
Identification of single-phase materials, minerals, chemical compounds and ceramics.
Identification of multiple phase in microcrystalline mixture(rocks).
Determination of crystalline size and shape.
Crystallographic structural analysis and unit cell calculation from crystalline materials.
Particle size determination-Spot counting methods.
A brief history of discovery of structure of atoms - particles and rays, nuclear decays, radioactivity, X-ray production. For RADIATION ONCOLOGY students. Purely academic and non-commercial purpose.
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.
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.
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.
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 .
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.
2. INDEX
• CONCEPT
• ASTRONOMERS WHO SUGGESTED
EXISTENCE OF DARK MATTER
• OBSERVATIONAL EVIDENCE
• ALTERNATIVE THEORIES
• BARYONIC VS NON-BARYONIC
MATTER
• CLASSIFICATION
• POPULAR CULTURE
3. Concept
• CORRESPONDS TO THE 27% OF THE MASS AND ENERGY IN THE UNIVERSE.
• IT DOES NOT EMIT OR INTERACT WITH ELECTROMAGNETIC RADIATION.
• IT HAS NOT BEEN DIRECTLY OBSERVED, BUT ITS EXISTENCE IS DEDUCED FROM ITS
GRAVITATIONAL EFFECTS
• IS TRANSPARENT TO ELECTROMAGNETIC RADIATION AND IS SO DENSE AND SMALL THAT IT
CAN’T EMIT ENOUGH RADIATION TO BE DETECTABLE WITH OUR TECHNOLOGY.
• THE TOTAL MASS-ENERGY OF THE UNIVERSE CONTAINS 4.9% ORDINARY MATTER, 26.8%
DARK MATTER AND 68.3% DARK ENERGY.
5. Observational evidence
• Much of the evidence comes from the motions of galaxies. Galactic rotation curves,
illustrate the velocity of rotation versus the distance from the galactic center,
showing the "excess" velocity.
• Diffusse galaxies (galaxies with brightness lower than night sky) have an uncommon
low ratio of visible dark matter. Gravitational observations of galaxy clusters allow
direct estimates of the gravitational mass based on its effect on light coming from
other galaxies.
7. BARYONIC VS. NON-
BARYONIC MATTER
● Baryonic matter is made of protons and neutrons that make up
stars and planets.
● Nonbaryonic dark matter are hypothetical particles such as
axions particles.
8. CLASSIFICATION
● Dark matter can be divided into cold, warm and hot categories.
● The categories are set with respect to the size of a protogalaxy. Dark
matter particles are classified according as their Free Streaming
Length:
● much smaller than a protogalaxy (cold)
● similar to a protogalaxy (warm)
● or much larger than a protogalaxy (hot)
9. POPULAR CULTURE
• IT IS COMMONLY USE IN SCI-FI WORKS (SERIES, BOOKS…)
• USUALLY ATTRIBUTED TO EXTRAORDINARY PHYSICAL OR MAGICAL
PROPERTIES.
• DESCRIPTIONS ARE OFTEN INCONSISTENT
