Nitrogen is essential for ecosystems and life but it exists largely as unreactive nitrogen gas in the atmosphere. The nitrogen cycle involves four key processes - nitrogen fixation, ammonification, nitrification, and denitrification - that convert nitrogen between different chemical forms so it can be used by plants and other organisms. Nitrogen fixation involves bacteria and lightning converting nitrogen gas into forms plants can use. Ammonification and nitrification further transform nitrogen into ammonium and nitrates. Denitrification ultimately converts nitrogen back to its unreactive gas form through bacteria, balancing the nitrogen added through fixation.
This is a comprehensive account of the nitrogen cycle in terrestrial environments. The nitrogen cycle is responsible for the circulation of nitrogen between inorganic and organic components of the environment.
This is a comprehensive account of the nitrogen cycle in terrestrial environments. The nitrogen cycle is responsible for the circulation of nitrogen between inorganic and organic components of the environment.
The Nitrogen cycle is defined as the biogeochemical cycle process that involves transforming the inert nitrogen that is available in the atmosphere, into a more usable or conventional form, that can be actively used by plants, and various living organisms. Enroll now at Tutoroot.
Roles of microbes in nitrogen cycle aritriyaaritriyajana
There are many presentation on nitrogen cycle.but in my case i have to make a ppt on microbes role in nitrogen cycle.so i made it.and then upload it if anyone get help from it i will be pleased. Aritriya Jana(F.F.Sc)
prepared by Centurion university of technology and management, B.Sc Agriculture 1st year 2nd sem students;
Ram prasad Behera(180804130026)
Gargeya Ku. Naik(180804130001).
The Nitrogen cycle is defined as the biogeochemical cycle process that involves transforming the inert nitrogen that is available in the atmosphere, into a more usable or conventional form, that can be actively used by plants, and various living organisms. Enroll now at Tutoroot.
Roles of microbes in nitrogen cycle aritriyaaritriyajana
There are many presentation on nitrogen cycle.but in my case i have to make a ppt on microbes role in nitrogen cycle.so i made it.and then upload it if anyone get help from it i will be pleased. Aritriya Jana(F.F.Sc)
prepared by Centurion university of technology and management, B.Sc Agriculture 1st year 2nd sem students;
Ram prasad Behera(180804130026)
Gargeya Ku. Naik(180804130001).
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.
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.
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.
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.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
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.
1. Nitrogen Cycle
Introduction
Nitrogen is also key in the existence of ecosystems and food chains. Nitrogen forms about 78% of the air
on earth. But plants do not use nitrogen directly from the air. This is because nitrogen itself is unreactive,
and cannot be used by green plants to make protein. Nitrogen gas therefore, needs to be converted into
nitrate compound in the soil by nitrogen-fixing bacteria in soil, root nodules or lightning.
Cycle
Four processes participate in the cycling of nitrogen through the biosphere:
Nitrogen fixation
Ammonification/mineralization
Nitrification
Denitrification
Nitrogen Fixation
The process of converting N2 into biologically available nitrogen is called nitrogen fixation. N2 gas is a
very stable compound due to the strength of the triple bond between the nitrogen atoms, and it requires a
large amount of energy to break this bond. The whole process requires eight electrons and at least sixteen
ATP molecules (Figure 2). As a result, only a select group of prokaryotes are able to carry out this
energetically demanding process. Although most nitrogen fixation is carried out by prokaryotes, some
nitrogen can be fixed abiotically by lightning or certain industrial processes, including the combustion of
fossil fuels.
Three processes are responsible for most of the nitrogen fixation in the biosphere:
Atmospheric fixation by lightning
industrial fixation
Biological fixation by certain microbes — alone or in a symbiotic relationship with some plants
and animals
Atmospheric Fixation:
The enormous energy of lightning breaks nitrogen molecules and enables their atoms to combine
with oxygen in the air forming nitrogen oxides. These dissolve in rain, forming nitrates, that are carried to
the earth. Atmospheric nitrogen fixation probably contributes some 5– 8% of the total nitrogen fixed.
Industrial Fixation:
Under great pressure, at a temperature of 600°C, and with the use of a catalyst, atmospheric nitrogen
and hydrogen (usually derived from natural gas or petroleum) can be combined to form ammonia (NH3).
Ammonia can be used directly as fertilizer, but most of its is further processed to urea and ammonium
nitrate (NH4NO3).
2. Biological Fixation:
The ability to fix nitrogen is found only in certain bacteria and archaea.
Some live in a symbiotic relationship with plants of the legume family (e.g., soybeans, alfalfa).
Some establish symbiotic relationships with plants other than legumes (e.g., alders).
Some establish symbiotic relationships with animals, e.g., termites and "shipworms" (wood-
eating bivalves).
Some nitrogen-fixing bacteria live free in the soil.
Nitrogen-fixing cyanobacteria are essential to maintaining the fertility of semi-aquatic
environments like rice paddies.
Biological nitrogen fixation requires a complex set of enzymes and a huge expenditure of ATP.
Ammonification / mineralization:
After nitrogen is incorporated into organic matter, it is often converted back into inorganic nitrogen by
a process called nitrogen mineralization, otherwise known as decay. When organisms die, decomposers
(such as bacteria and fungi) consume the organic matter and lead to the process of decomposition. During
this process, a significant amount of the nitrogen contained within the dead organism is converted to
ammonium. Once in the form of ammonium, nitrogen is available for use by plants or for further
transformation into nitrate (NO3
-
) through the process called nitrification.
Organic N → NH4
+
Nitrification
Some of the ammonium produced by decomposition is converted to nitrate (NO3
-
) via a process
called nitrification. The bacteria that carry out this reaction gain energy from it. Nitrification requires the
presence of oxygen, so nitrification can happen only in oxygen-rich environments like circulating or
flowing waters and the surface layers of soils and sediments. The process of nitrification has some
important consequences. Ammonium ions (NH4
+
) are positively charged and therefore stick (are sorbed)
to negatively charged clay particles and soil organic matter. The positive charge prevents ammonium
nitrogen from being washed out of the soil (or leached) by rainfall. In contrast, the negatively charged
nitrate ion is not held by soil particles and so can be washed out of the soil, leading to decreased soil
fertility and nitrate enrichment of downstream surface and groundwater.
NH4
+
→ NO3
-
Denitrification
Through denitrification, oxidized forms of nitrogen such as nitrate (NO3
-
) and nitrite (NO2
-
) are converted
to dinitrogen (N2) and, to a lesser extent, nitrous oxide gas (NO2). Denitrification is an
anaerobic process that is carried out by denitrifying bacteria, which convert nitrate to dinitrogen in the
following sequence:
NO3
-
→ N2+ N2O
NO3
-
→ NO2
-
→ NO → N2O → N2.
3. Nitric oxide and nitrous oxide are gases that have environmental impacts. Nitric oxide (NO) contributes
to smog, and nitrous oxide (N2O) is an important greenhouse gas, thereby contributing to
global climate change.
Once converted to dinitrogen, nitrogen is unlikely to be reconverted to a biologically available form
because it is a gas and is rapidly lost to the atmosphere. Denitrification is the only nitrogen transformation
that removes nitrogen from ecosystems (essentially irreversibly), and it roughly balances the amount of
nitrogen fixed by the nitrogen fixers described above.