Now let K be a homologically trivial transverse knot in a contact 3–manifold (M, ξ), with M oriented such that ξ is a positive contact structure. Let Σ be a Seifert surface for K. As in the definition of the rotation number, we make use of the fact that the plane field ξ|Σ is trivial. Choose a non-vanishing section X of ξ|Σ and push K in the direction of X to obtain a parallel copy K’ of K.
— Hansjörg Geiges  (2008)

It is important to look at the results of this meta-analysis with a critical eye in light of two facts: the average training took place over the course of 20 days, and the L2 setting encouraged larger gains than the FL environment. […] [E]very attempt was made to contact the author(s) and retrieve necessary data. […] (The topic of generalization is discussed in more detail in the Discussion section of this article.)
— Sakai & Moorman (2018)

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Efectivamente, a seção, o fato e o contato. Quando? Hoje. Onde?

No sítio do costume.

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