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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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Formal Problems in Biomechanics

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Dr. Rishabh Pathak


Formal problems in biomechanics typically involve applying mathematical and physics principles to analyze and solve complex biomechanical scenarios. These problems often require a deep understanding of human movement, forces, torques, energy, and motion analysis. Here are some examples of formal problems in biomechanics:


1.     Joint Forces and Torques: Calculate the forces and torques acting on a specific joint during a particular movement, such as knee forces during squatting or shoulder torques during overhead throwing.


2.     Muscle Moment Arms: Determine the moment arms of muscles around a joint to analyze their mechanical advantage and contribution to joint movement and stability.


3.     Center of Mass Calculations: Calculate the center of mass of a body segment or the whole body in different positions to understand balance, stability, and movement coordination.


4.     Impulse-Momentum Analysis: Use impulse-momentum principles to analyze the forces and accelerations involved in a specific movement, such as jumping, running, or throwing.


5.  Energy Expenditure Calculations: Calculate the energy expenditure during different activities or exercises based on metabolic equations, work done, and power output.


6.  Gait Analysis: Analyze the kinematics and kinetics of human gait to assess walking or running patterns, joint angles, ground reaction forces, and muscle activations.


7.   Projectile Motion: Solve problems related to projectile motion, such as calculating the range, height, velocity, and angle of projection of a thrown object or a jumping athlete.


8.   Mechanical Work and Power: Calculate the mechanical work done and power generated by muscles during specific movements or exercises, such as lifting weights or cycling.


9.   Stress and Strain Analysis: Analyze the stress and strain distribution in bones, tendons, or ligaments under different loading conditions to assess injury risk and mechanical properties.


10. Biomechanical Modeling: Develop biomechanical models to simulate and analyze complex movements, such as sports techniques, rehabilitation exercises, or ergonomic tasks.


These formal problems require a combination of theoretical knowledge, mathematical skills, data analysis techniques, and critical thinking to derive meaningful insights into human movement mechanics and performance. By practicing formal biomechanical problems and applying analytical approaches, researchers, practitioners, and students can deepen their understanding of biomechanics and enhance their problem-solving abilities in this interdisciplinary field.

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