This document contains information about chemistry concepts including molecules, ions, atomic number, and mass number. It begins with learning outcomes and definitions of molecules as combinations of atoms. It then discusses atomic number as the number of protons and mass number as the total protons and neutrons. Examples are given to illustrate these concepts. The document ends with an activity and quiz to assess understanding of atomic and mass numbers.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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.
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.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
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.
(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.
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.
4. Learning Outcomes:
At the end of the lesson, I can:
• Differentiate among atoms,
molecules, ions and give
examples.
4
5. Molecules and Ions
Molecules
A molecule is an aggregate of at
least two atoms in a definite
arrangement held together by
chemical forces (also called
chemical bonds).
5
6. Molecules and Ions
Molecules
A molecule may contain atoms
of the same element or atoms of
two or more elements joined in
a fixed ratio, in accordance with
the law of definite proportions.
6
9. Atomic and Mass Number
Each atom has a certain number
of protons, electrons, and
neutrons. But no matter how
particles are present in an atom,
the number of electrons will
usually be the same with the
number of protons.
9
10. Atomic and Mass Number
If the number of the protons and
electrons are the same, the
atom is considered electrically
neutral. It means that the net
charge of the atom is zero; the
atom is also considered stable.
10
11. Atomic and Mass Number
Neutral Atom
• Number of Proton (+)
equals Number of Electrons
(-)
• Positive protons plus
negative neutrons equals
zero. 11
12. Atomic Number
The atomic number (Z) is
equivalent to the number of
protons present in the nucleus of
an atom.
12
13. Atomic Number
Example:
All the atoms of sodium have an
atomic number of 11, which
denotes that they all contain 11
protons each. The atomic
number for each element can be
found in the periodic table of
elements. 13
14. Mass Number
The mass number (M) is the
total number of protons and
neutrons in an atom. The atomic
mass is the average of the
masses of all the known isotopes
of an element.
14
15. Mass Number
Mass number are relative whole
numbers, while atomic masses
have decimals because they
have an average.
15
16. Atomic and Mass Number
• Atomic Number = No. of Proton
• No. of Proton = No. of Electrons
• No. of Neutron =Mass Number
minus Atomic Number
• Mass Number=No. of Protons
plus No. of Neutrons
16
18. Activity 2.4 - Atomic and Mass
Number
18
Symbol
Atomic
Number
Mass
Number
Number of
Protons
Number of
Electrons
Number
of
Neutrons
40
Ca 20 40 20 20 20
20
79
Se
34
35
Cl
17
21. Quiz 2.4 - Atomic and Mass
Number
21
Symbol
Atomic
Number (Z)
Mass
Number
(A)
Number of
Protons
Number of
Electrons
Number of
Neutrons
Al 13 14
Br 35 80
Cu 64 29
N 7 7
22. Quiz 2.4 - Atomic and Mass
Number
22
Symbol
Atomic
Number (Z)
Mass
Number
(A)
Number of
Protons
Number of
Electrons
Number of
Neutrons
I 53 127
Ag 47 61
Na 11 23
Ca 20 20
23. Quiz 2.4 - Atomic and Mass
Number
23
Symbol
Atomic
Number (Z)
Mass
Number
(A)
Number of
Protons
Number of
Electrons
Number of
Neutrons
Zn 65 35
B 5 11
Kr 36 84
24. Quiz 2.4 – Answer Key
24
Symbol
Atomic
Number (Z)
Mass
Number
(A)
Number of
Protons
Number of
Electrons
Number of
Neutrons
Al 13 27 13 13 14
Br 35 80 35 35 45
Cu 29 64 29 29 35
N 7 14 7 7 7
25. Quiz 2.4 – Answer Key
25
Symbol
Atomic
Number (Z)
Mass
Number
(A)
Number of
Protons
Number of
Electrons
Number of
Neutrons
I 53 127 53 53 74
Ag 47 108 47 47 61
Na 11 23 11 11 12
Ca 20 40 20 20 20
Editor's Notes
Answer: The illustration shows two laws, namely, the law of conservation of matter and the law of definite proportion. The number of elements on the left is the same to that on the right, thus obeying the first law mentioned. Also, the law of definite composition or multiple proportions is also evident because both illustrations have the same type of elements, but they differ in the number of atoms.
