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Uncertainty in Multiclass Classification

Dr. Rishabh Pathak
1. What is Uncertainty in Classification? Uncertainty refers to the model’s confidence or doubt in its predictions. Quantifying uncertainty is important to understand how reliable each prediction is. In multiclass classification , uncertainty estimates provide probabilities over multiple classes, reflecting how sure the model is about each possible class. 2. Methods to Estimate Uncertainty in Multiclass Classification Most multiclass classifiers provide methods such as: predict_proba: Returns a probability distribution across all classes. decision_function: Returns scores or margins for each class (sometimes called raw or uncalibrated confidence scores). The probability distribution from predict_proba captures the uncertainty by assigning a probability to each class. 3. Shape and Interpretation of predict_proba in Multiclass Output shape: (n_samples, n_classes) Each row corresponds to the probabilities of ...
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Microscopic Structure of Bone

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Dr. Rishabh Pathak

The microscopic structure of bone tissue reveals a hierarchical organization that contributes to its strength, flexibility, and functionality. The key components of the microscopic structure of bone include:


1.    Osteon (Haversian System):

o    The basic structural unit of compact bone tissue.

o    Consists of concentric lamellae (layers) of bone matrix surrounding a central Haversian canal.

o    The Haversian canal contains blood vessels, nerves, and lymphatics that supply nutrients and remove waste products from bone cells.

o    Osteocytes are housed in lacunae within the lamellae and communicate with each other and with blood vessels through canaliculi (tiny channels).

2.    Lamellae:

o    Layers of bone matrix that make up the concentric rings within an osteon.

o    Collagen fibers in the lamellae provide tensile strength and flexibility to bone tissue.

o    Lamellae are arranged in different orientations to resist mechanical stresses and distribute loads effectively.

3.    Interstitial Lamellae:

o    Fill the spaces between intact osteons or remnants of old osteons.

o    Represent areas where bone remodeling has occurred or where new osteons are being formed.

4.    Circumferential Lamellae:

o    Encircle the outer and inner surfaces of compact bone, providing structural support and strength to the bone.

o    Help resist torsional forces and maintain the cylindrical shape of long bones.

5.    Trabeculae:

o    Found in spongy (cancellous) bone, forming a network of interconnected bony struts.

o    Trabeculae provide structural support, help distribute forces, and contain red bone marrow for hematopoiesis.

o    Spaces between trabeculae are filled with bone marrow and blood vessels.

6.    Bone Marrow:

o    Red bone marrow within trabecular spaces is the site of hematopoiesis, producing blood cells.

o    Yellow bone marrow in the medullary cavity of long bones stores fat and serves as an energy reserve.

7.    Periosteum and Endosteum:

o    The periosteum covers the outer surface of bones, providing a protective and nourishing layer.

o    The endosteum lines the inner surfaces of bones and contains osteoprogenitor cells involved in bone remodeling and repair.

8.    Cement Lines:

o    Thin, mineralized lines that mark the boundaries between adjacent osteons or lamellae.

o    Represent sites of previous bone deposition and remodeling.

The intricate microscopic structure of bone tissue, including osteons, lamellae, trabeculae, bone marrow, and connective tissues, reflects its adaptation to withstand mechanical stresses, support metabolic functions, and maintain skeletal integrity. Understanding the microscopic organization of bone is crucial for comprehending its biomechanical properties, remodeling processes, and role in overall musculoskeletal health.

 

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