Radiology & Imaging

Gold makes invisible surfaces visible in CT

Today, the three-dimensional visualization and analysis of biological samples using computer tomography (CT) is a routine procedure. However, in the past, it was very difficult to visualize the fine surface details of many ...

Diseases, Conditions, Syndromes

Scientists discover how superbugs hide from their host

New research led by the University of Sheffield has discovered how a hospital superbug evades the immune system to cause infection – paving the way for new treatments.


New potential therapeutic target for pancreatic cancer discovered

Cancer cells demand enormous amounts of molecular "food" to survive and grow, and a study published March 27 online in Nature by researchers at The University of Texas MD Anderson Cancer Center may have identified a new approach ...

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In mathematics, specifically in topology, a surface is a two-dimensional topological manifold. The most familiar examples are those that arise as the boundaries of solid objects in ordinary three-dimensional Euclidean space R3 — for example, the surface of a ball or bagel. On the other hand, there are surfaces which cannot be embedded in three-dimensional Euclidean space without introducing singularities or intersecting itself — these are the unorientable surfaces.

To say that a surface is "two-dimensional" means that, about each point, there is a coordinate patch on which a two-dimensional coordinate system is defined. For example, the surface of the Earth is (ideally) a two-dimensional sphere, and latitude and longitude provide coordinates on it — except at the International Date Line and the poles, where longitude is undefined. This example illustrates that not all surfaces admits a single coordinate patch. In general, multiple coordinate patches are needed to cover a surface.

Surfaces find application in physics, engineering, computer graphics, and many other disciplines, primarily when they represent the surfaces of physical objects. For example, in analyzing the aerodynamic properties of an airplane, the central consideration is the flow of air along its surface.

This text uses material from Wikipedia, licensed under CC BY-SA