scholarly journals Two Notes on the Theoretical Physics of ATP Synthase

2022 ◽  
Author(s):  
Archit Chaturvedi
Keyword(s):  
Angular Momentum ◽  
Kinetic Energy ◽  
Atp Synthase ◽  
Linear Acceleration ◽  
Theoretical Physics ◽  
Cellular Respiration ◽  
Cellular Processes ◽  
Rotational Kinematics ◽  
The Moment ◽  
Insight Into

ATP Synthase is an essential molecule in cell and molecular biology. It is responsible for the production of ATP during cellular respiration, a molecule that provides the energy required to drive a number of cellular processes. In this paper, I explore the rotational physics of ATP Synthase’s rotor, a part of the protein that spins during the production of ATP. Firstly, I discuss some elementary rotational kinematics of the rotor. I then derive two alternate formulations for the total linear acceleration of the rotor. Finally, I derive formulas for the moment of inertia, angular momentum, net torque, and kinetic energy of the rotor. Through this, I hope to provide a theoretical and mathematical insight into the mechanics of ATP Synthase during the production of ATP.

scholarly journals Two Notes on the Theoretical Physics of ATP Synthase

2022 ◽  
Author(s):  
Archit Chaturvedi
Keyword(s):  
Angular Momentum ◽  
Kinetic Energy ◽  
Atp Synthase ◽  
Linear Acceleration ◽  
Theoretical Physics ◽  
Cellular Respiration ◽  
Cellular Processes ◽  
Rotational Kinematics ◽  
The Moment ◽  
Insight Into

Abstract ATP Synthase is an essential molecule in cell and molecular biology. It is responsible for the production of ATP during cellular respiration, a molecule that provides the energy required to drive a number of cellular processes. In this paper, I explore the rotational physics of ATP Synthase’s rotor, a part of the protein that spins during the production of ATP. Firstly, I discuss some elementary rotational kinematics of the rotor. I then derive two alternate formulations for the total linear acceleration of the rotor. Finally, I derive formulas for the moment of inertia, angular momentum, net torque, and kinetic energy of the rotor. Through this, I hope to provide a theoretical and mathematical insight into the mechanics of ATP Synthase during the production of ATP.

scholarly journals Magnetic Field Amplification and Polar Jet Formation in Protostars

1987 ◽  
Vol 115 ◽  
pp. 384-384
Author(s):  
S. Hinata
Keyword(s):  
Magnetic Field ◽  
Angular Momentum ◽  
Kinetic Energy ◽  
Accretion Disk ◽  
Outer Edge ◽  
Moment Of Inertia ◽  
Simple Relationship ◽  
Field Amplification ◽  
Background Magnetic Field ◽  
The Moment

There is a simple relationship among moment of inertia I, rotational kinetic energy K, and momentum L given by (David Layzer, private communication), 2IK ≧ L. During the Hayashi phase a rotating protostar will amplify the trapped magnetic field by a dynamo-like process. Since the rotation is expected to be fast, many unstable modes will be excited and will grow exponentially in time until some nonlinear processes saturate the amplitude. However, it may happen that the reduction in rotational kinetic energy becomes so large that without increasing the moment of inertia the inequality given above may not be satisfied. The only way to increase the moment of inertia is to move the mass outward. This can be done by transferring the angular momentum outward through the magnetic field. So we will have a fast rotating mass shell at the outer edge of the star. Further transfer of angular momentum will push the shell against the accretion disk; the moving masses of the disk will divert the mass flow along the background magnetic field which extends perpendicular to the accretion disk. This results in the hollow cone jets from both poles because the outward motion is primarily on the equatorial plane.

scholarly journals Investigation of the molecular signatures of selection on ATP synthase genes in the marine bivalve Limecola balthica

2019 ◽  
Vol 32 ◽  
pp. 3 ◽  
Author(s):  
Eric Pante ◽  
Vanessa Becquet ◽  
Amélia Viricel ◽  
Pascale Garcia
Keyword(s):  
Atp Synthase ◽  
Sequence Data ◽  
Nuclear Gene ◽  
Cellular Respiration ◽  
Marine Bivalve ◽  
Gamma Subunit ◽  
Genetic Barriers ◽  
Different Populations ◽  
Peptide Interaction ◽  
Evolutionarily Stable

We used transcriptomic sequence data to describe patterns of divergence and selection across different populations of a marine bivalve (Limecola balthica). Our analyses focused on a nuclear gene (atp5c1) that was previously detected in an FST scan as highly structured among populations separated by the Finistère Peninsula in France. This gene encodes the gamma subunit of the FO/F1 ATP synthase, a multi-protein complex that is paramount to cellular respiration and energy production. Analysis of non-synonymous to synonymous mutation ratios revealed that 65% of the gene is highly conserved (dN/dS ≤ 0.1, min = 0), while 6% of the gene is likely under positive selection (dN/dS ≥ 1, max = 2.03). All replacement mutations are clustered on a 46 residues portion of the protein, within an inter-peptide interaction zone. Comparative genomics suggests that these mutations are evolutionarily stable, and we hypothesize that they are involved in inter-population genetic incompatibilities with other subunits of the ATP synthase complex. The protein stability of the gamma subunit conferred by southern variants was inferred to be higher under warmer temperatures, suggesting that environmental conditions may contribute to the strength of genetic barriers in L. balthica.

scholarly journals Rotational broadening and conservation of angular momentum in post-extreme horizontal branch stars

2018 ◽  
Vol 613 ◽  
pp. A66
Author(s):  
G. Fontaine ◽  
M. Latour
Keyword(s):  
Angular Momentum ◽  
Rotation Speed ◽  
Momentum Conservation ◽  
Evolutionary Models ◽  
Horizontal Branch ◽  
Natural Consequence ◽  
Average Value ◽  
Horizontal Branch Stars ◽  
The Moment ◽  
Ehb Stars

We show that the recent realization that isolated post-extreme horizontal branch (post-EHB) stars are generally characterized by rotational broadening with values of V rot sini between 25 and 30 km s−1 can be explained as a natural consequence of the conservation of angular momentum from the previous He-core burning phase on the EHB. The progenitors of these evolved objects, the EHB stars, are known to be slow rotators with an average value of V rot sini of ~7.7 km s−1. This implies significant spin-up between the EHB and post-EHB phases. Using representative evolutionary models of hot subdwarf stars, we demonstrate that angular momentum conservation in uniformly rotating structures (rigid-body rotation) boosts that value of the projected equatorial rotation speed by a factor ~3.6 by the time the model has reached the region of the surface gravity-effective temperature plane where the newly-studied post-EHB objects are found. This is exactly what is needed to account for their observed atmospheric broadening. We note that the decrease of the moment of inertia causing the spin-up is mostly due to the redistribution of matter that produces more centrally-condensed structures in the post-EHB phase of evolution, not to the decrease of the radius per se.

scholarly journals Crystallographic insight into the catalytic mechanism of subunit A of the A-ATP synthase and the P-loop switch in evolution

2010 ◽  
Vol 1797 ◽  
pp. 32-33
Author(s):  
Anil Kumar ◽  
Malathy Sony Subramanian Manimekalai ◽  
Asha Manikkoth Balakrishna ◽  
Gerhard Grüber
Keyword(s):  
Atp Synthase ◽  
Catalytic Mechanism ◽  
Subunit A ◽  
Insight Into

Some measurements of the flux of infra-red radiation in the atmosphere

1956 ◽  
Vol 236 (1205) ◽  
pp. 175-186 ◽  
Keyword(s):  
Kinetic Energy ◽  
Lower Stratosphere ◽  
Atmospheric Radiation ◽  
Radiative Cooling ◽  
Classical View ◽  
Upper Troposphere ◽  
Infra Red ◽  
The Moment ◽  
Effective Radiation ◽  
Red Radiation

For the continual development of the kinetic energy of the winds, it is necessary for the upper troposphere to be cooled by radiation. Results are reported of nine aircraft ascents on which the upward and downward flows of infra-red radiation were measured and com­pared with values calculated using the radiation charts of Elsasser and Yamamoto. The divergence of radiative flux deduced from these measurements clearly shows that the cooling in the troposphere is not very different from that calculated from radiation charts. The importance of clouds on the radiative pattern is demonstrated; at the moment, incom­plete knowledge of cloud structure will be the chief factor limiting the value of calculations of atmospheric radiation. The measurements are of very limited value in the stratosphere, since, for the very small quantities of water there, the effective radiation is in the rotation band of water vapour ( λ between 30 and 70 μ ) and the radiometer used was not sensitive to these wavelengths. If the use of radiation charts is extrapolated to these conditions they indicate that the radiative cooling continues in the lower stratosphere. This is in contrast with the ‘classical’ view that the stratosphere is in radiative equilibrium.

Temperature and Time of Development of the Two Sexes in Drosophila

1926 ◽  
Vol 4 (2) ◽  
pp. 186-195 ◽  
Author(s):  
GERT BONNIER
Keyword(s):  
Statistical Significance ◽  
Pupal Stage ◽  
The Other ◽  
Female Development ◽  
Short Intervals ◽  
Influence Of Temperature On ◽  
The Times ◽  
The Moment ◽  
First Time ◽  
Insight Into

1. The time of development at 25°C. up to the moment of pupation is found to be for females and males respectively 116.62 ± 0.19 and 116.78 ± 0.20 hours. During the pupal stage the two times are 111.36 ± 0.15 and 115.46 ± 0.13 hours. 2. At 30° C. the corresponding figures are (in the same order): 99.95 ± 0.49, 103.37 ± 0.43, 78±15 ± 0.50 and 84.26 ± 0.34 hours. 3. These figures show that there is a statistical significance in the differences of the times of development of the two sexes for both the periods at 30°C. but only for the pupal stage at 25° C. It is pointed out that the fact that the longer time of male development as compared with female development at 25° C. is confined to the pupal stage, may be correlated with the other fact that the essential parts of the secondary sexual characters are developed during this stage. 4. It is shown that there is a negative correlation between the pre-pupal and pupal times of development, indicating that the longer the first time is, the shorter is, as a rule, the other time and vice versa. 5. With the aid of statistical methods it is shown that the shortening of the time of development at 30°C. as compared with the time at 25° C. is much more pronounced for the pupal than for the pre-pupal stage. 6. This last fact is discussed and it is emphasised that the ordinary methods of studying the influence of temperature on development are too rough to be of more than of a descriptive value, the only way of getting a deeper insight into the processes of development by temperature studies being the separate studies of a number of short intervals.

The Moment I Realized I Had to Give Back by Teaching

2019 ◽  
pp. 171-185
Author(s):  
Deborah McPhee
Keyword(s):  
Quality Of Life ◽  
Higher Education ◽  
Scholastic Achievement ◽  
Mentoring Program ◽  
Average Student ◽  
The Moment ◽  
The Right ◽  
Returning To School ◽  
Insight Into

The author provides insight into surviving a traumatic, life-altering experience and returning to school to finish attaining a degree later in life. Completing the process of gaining a higher education can be more than simply rewarding, for a survivor, for someone older than the average student, or for someone simply searching for their place in life. The journey can help people recover, overcome obstacles and fears, and not only put their lives back together, but improve their quality of life. Finding the right school and a mentoring program, one that helps guide a student through a higher education, can be more than a scholastic achievement; it can be a part of the process of rebuilding a life and moving on. In fact, it can be transforming and inspiring. This chapter examines the process and offers insight and advice on the importance of reaching goals, despite any obstacles.

scholarly journals Secular Mass Loss from Cataclysmic Variables

1977 ◽  
Vol 42 ◽  
pp. 365-370
Author(s):  
Józef Smak
Keyword(s):  
Mass Transfer ◽  
Angular Momentum ◽  
Chemical Composition ◽  
Mass Loss ◽  
Cataclysmic Variables ◽  
Dynamical Evolution ◽  
Good Insight ◽  
Physical Mechanisms ◽  
Cataclysmic Binaries ◽  
Insight Into

The mass loss from cataclysmic binaries seems an important and worth studying phenomenon for a number of reasons. It is probably enough to mention only two of them:(a) Whenever we can directly observe the ejected material, determine its amount and the rate of mass loss, as well as its chemical composition (this being the case of the expanding envelopes of novae), we are getting a good insight into the basic physical mechanisms responsible for the observed phenomena.(b) The mass loss (together with the mass transfer) and the loss of the orbital angular momentum are related directly to the dynamical evolution of a binary system and - indirectly - to the evolution of its components.

scholarly journals Effects of rotational submarine slump dynamics on tsunami genesis: new insight from idealized models and the 1929 Grand Banks event

2020 ◽  
Vol 500 (1) ◽  
pp. 41-61 ◽  
Author(s):  
T. Zengaffinen ◽  
F. Løvholt ◽  
G. K. Pedersen ◽  
C. B. Harbitz
Keyword(s):  
Source Information ◽  
Physical Processes ◽  
Viscoplastic Model ◽  
Grand Banks ◽  
Rotational Kinematics ◽  
Short Run ◽  
Submarine Slump ◽  
Geological Source ◽  
Insight Into

AbstractSediment slumps are known to have generated important tsunamis such as the 1998 Papua New Guinea (PNG) and the 1929 Grand Banks events. Tsunami modellers commonly use solid blocks with short run-out distances to simulate these slumps. While such methods have the obvious advantage of being simple to use, they offer little or no insight into physical processes that drive the events. The importance of rotational slump motion to tsunamigenic potential is demonstrated in this study by employing a viscoplastic landslide model with Herschel–Bulkley rheology. A large number of simulations for different material properties and landslide configurations are carried out to link the slump's deformation, rheology, its translational and rotational kinematics, to its tsunami genesis. The yield strength of the slump is shown to be the primary material property that determines the tsunami genesis. This viscoplastic model is further employed to simulate the 1929 Grand Banks tsunami using updated geological source information. The results of this case study suggest that the viscoplastic model can be used to simulate complex slump-induced tsunami. The simulations of the 1929 Grand Banks event also indicate that a pure slump mechanism is more tsunamigenic than a corresponding translational landslide mechanism.

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