Skip to main content

Energy Manifold Natural Gradient Descent: From Riemannian Optimization to Modern Neuroscience, NeuroAI and Quantum Physics

Dr. Rishabh Pathak
When Geometry, Energy, Artificial Intelligence and Neuroscience Converge Modern Artificial Intelligence is rapidly moving beyond the idea that learning simply means minimizing an error function. Increasingly, researchers are asking a deeper question: what is the structure of the space in which learning takes place? This question becomes particularly important when the system being modelled is constrained, nonlinear, dynamic, or governed by physical principles. A recent work titled “Energy Manifold Natural Gradient Descent: Riemannian Optimization for Neural PDE Solvers” , by Zhangyong Liang and Huanhuan Gao, introduces Energy Manifold Natural Gradient Descent (EMNGD) , a mathematical framework that extends energy-based natural-gradient optimization from unconstrained Euclidean parameter spaces to constrained Riemannian parameter manifolds . At its core, the framework proposes a simple but powerful principle: An optimization algorithm should not only determine how to reduce error; it sh...
Post a Comment

Regulation Of Phosphatidic Acid Synthesis at The Exocytotic Site: Implication of GTPASES And Kinases

Image
Dr. Rishabh Pathak

Regulation of phosphatidic acid synthesis at the exocytotic site involves the intricate interplay of GTPases and kinases, which play crucial roles in modulating lipid metabolism and membrane dynamics during exocytosis. Here is an overview of how GTPases and kinases are implicated in the regulation of phosphatidic acid synthesis at the exocytotic site:


1.      GTPases in Phosphatidic Acid Synthesis:

o    Rab GTPases: Rab GTPases are key regulators of vesicle trafficking and membrane fusion during exocytosis. They control the spatial and temporal dynamics of membrane trafficking events.

o    Arf GTPases: Arf GTPases are involved in vesicle formation, cargo sorting, and vesicle budding at the Golgi apparatus and endosomes. They regulate membrane trafficking pathways that impact phospholipid metabolism.

o Rho GTPases: Rho GTPases play a role in actin cytoskeleton dynamics and membrane remodeling. They can influence lipid metabolism indirectly by modulating cytoskeletal organization and membrane curvature.

2.     Kinases in Phosphatidic Acid Synthesis:

o    PI3K (Phosphoinositide 3-Kinase): PI3Ks are key enzymes that phosphorylate phosphatidylinositol lipids, generating phosphoinositides that serve as signaling molecules. They regulate membrane trafficking and vesicle fusion events during exocytosis.

o    PLD (Phospholipase D): PLD enzymes catalyze the hydrolysis of phosphatidylcholine to generate phosphatidic acid. They are involved in membrane remodeling, vesicle trafficking, and exocytosis.

o    PKC (Protein Kinase C): PKC isoforms can phosphorylate and regulate enzymes involved in phosphatidic acid metabolism. They modulate membrane dynamics and protein interactions at the exocytotic site.

3.     Implications for Exocytosis:

o Membrane Fusion: GTPases and kinases regulate membrane fusion events by modulating lipid composition and membrane curvature at the exocytotic site.

o Vesicle Docking and Priming: These signaling molecules influence vesicle docking, priming, and fusion with the plasma membrane, essential steps in neurotransmitter release.

o  Regulation of SNARE Complexes: GTPases and kinases may impact the assembly and function of SNARE complexes, which are essential for vesicle fusion and neurotransmitter release.

4.    Integration of Signaling Pathways:

o    Cross-Talk: GTPases and kinases interact with multiple signaling pathways involved in exocytosis, including calcium signaling, cytoskeletal dynamics, and protein phosphorylation cascades.

o    Fine-Tuning Exocytosis: The coordinated action of GTPases and kinases allows for precise regulation of phosphatidic acid synthesis and membrane dynamics during exocytosis.

o    Neuronal Communication: Proper regulation of lipid metabolism at the exocytotic site by GTPases and kinases is essential for efficient neuronal communication and synaptic transmission.

Understanding how GTPases and kinases regulate phosphatidic acid synthesis at the exocytotic site provides insights into the molecular mechanisms underlying neurotransmitter release and synaptic function. Dysregulation of these signaling pathways may impact synaptic vesicle dynamics and neurotransmission, highlighting the importance of GTPases and kinases in maintaining proper neuronal function.

 

Categories:

Comments

Post a Comment

Popular posts from this blog

Cell Maturation (Dendrite and Axon Growth)

Dr. Rishabh Pathak
Cell maturation, encompassing dendrite and axon growth, is a crucial stage of brain development where neurons undergo structural changes to establish connections and form functional neural circuits. Here is an overview of cell maturation in the context of dendrite and axon growth: 1.      Dendrite Growth : o     Definition : Dendrites are branched extensions of a neuron that receive signals from other neurons and transmit these signals to the cell body. o     Dendritic Arborization : During maturation, neurons extend and elaborate their dendritic arbors, increasing the surface area available for synaptic connections. o     Synaptic Integration : Dendritic growth is essential for forming synapses with other neurons, allowing for the integration of incoming signals and information processing. o     Activity-Dependent Plasticity : Dendritic growth can be influenced by neural activity and sensory experiences, sh...
Post a Comment
Read more

Amphiarthrodial or Cartilaginous Joints

Dr. Rishabh Pathak
Amphiarthrodial joints, also known as cartilaginous joints, are joints where the adjacent bones are connected by cartilage. These joints allow for limited movement and provide both stability and flexibility to the skeletal system. Here is an overview of amphiarthrodial or cartilaginous joints: Amphiarthrodial or Cartilaginous Joints: 1.     Structure : o     Cartilage : §   Amphiarthrodial joints are characterized by the presence of cartilage between the articulating surfaces of the bones. §   The cartilage can be hyaline cartilage or fibrocartilage, depending on the specific joint and its function. o     Lack of Joint Cavity : §   Similar to fibrous joints, cartilaginous joints do not have a synovial cavity, and the bones are held together by the cartilaginous tissue. 2.     Types : o     Synchondroses : §   Synchondroses are cartilaginous joints where the connecting material is hyaline carti...
Post a Comment
Read more

Unrestricted Sampling

Dr. Rishabh Pathak
Unrestricted sampling, also known as simple random sampling, is a fundamental sampling technique where each element in the population has an equal and independent chance of being selected for the sample. In unrestricted sampling: 1.     Equal Probability of Selection : §   In simple random sampling, every element in the population has an equal probability of being chosen for the sample. This ensures that each unit is selected independently of other units, without any bias towards specific elements. 2.     Random Selection : §   The selection of sample elements is done randomly, without any systematic pattern or predetermined order. This randomness is essential to ensure that the sample is representative of the population and to minimize selection bias. 3.     Independence of Selection : §   Each selection is made independently of previous selections, meaning that the inclusion or exclusion of one element does not influence the ...
Post a Comment
Read more

Beta Activity compared to Muscles Artifacts

Dr. Rishabh Pathak
Beta activity in EEG recordings can sometimes be confused with muscle artifacts due to their overlapping frequency components. Frequency Components : o   Muscle artifacts often have frequency components of 25 Hz and greater, which can overlap with the frequency range of beta activity. o   Beta activity in EEG recordings typically falls within the beta frequency range of 13-30 Hz, with variations based on specific brain states and cognitive processes. 2.      Waveform Characteristics : o   Electromyographic (EMG) artifacts, which represent muscle activity, have distinct waveform characteristics that can help differentiate them from beta activity. o   EMG artifacts may exhibit a sharper contour with less rhythmicity, especially when the high-frequency filter is set at 70 Hz or higher, compared to the smoother contour and rhythmicity of beta activity. 3.      High-Frequency Filter Settings : o   Adjusting the high-frequency f...
Post a Comment
Read more

Distinguishing Features of Electrode Artifacts

Dr. Rishabh Pathak
Electrode artifacts in EEG recordings can present with distinct features that differentiate them from genuine brain activity.  1.      Types of Electrode Artifacts : o Variety : Electrode artifacts encompass several types, including electrode pop, electrode contact, electrode/lead movement, perspiration artifacts, salt bridge artifacts, and movement artifacts. o Characteristics : Each type of electrode artifact exhibits specific waveform patterns and spatial distributions that aid in their identification and differentiation from true EEG signals. 2.    Electrode Pop : o Description : Electrode pop artifacts are characterized by paroxysmal, sharply contoured transients that interrupt the background EEG activity. o Localization : These artifacts typically involve only one electrode and lack a field indicating a gradual decrease in potential amplitude across the scalp. o Waveform : Electrode pop waveforms have a rapid rise and a slower fall compared to in...
Post a Comment
Read more