Fighting a losing battle to tackle growth in plastic production | Letters

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When Rebekah Lee was in her twenties, she decided to embark on an ambitious climb up Mount Stuart in Washington State and "made a series of bad decisions".

WithTimeoutCause works. But there’s a subtlety in how it interacts with defer cancel()

за БПЛА。业内人士推荐电影作为进阶阅读

Назван простой способ улучшить состояние людей с деменциейA&MH: Медитация, йога и тайцзи уменьшают тревогу и стресс при деменции

UpdateClass[*Ps: Member]: A special form that updates an

Peripheral

A Riemannian metric on a smooth manifold \(M\) is a family of inner products \[g_p : T_pM \times T_pM \;\longrightarrow\; \mathbb{R}, \qquad p \in M,\] varying smoothly in \(p\), such that each \(g_p\) is symmetric and positive-definite. In local coordinates the metric is completely determined by its values on basis tangent vectors: \[g_{ij}(p) \;:=\; g_p\!\left(\frac{\partial}{\partial x^i}\bigg|_p,\; \frac{\partial}{\partial x^j}\bigg|_p\right), \qquad g_{ij} = g_{ji},\] with the matrix \((g_{ij}(p))\) positive-definite at every point. The length of a tangent vector \(v = \sum_i v^i \frac{\partial}{\partial x^i}\in T_pM\) is then \(\|v\|_g = \sqrt{\sum_{i,j} g_{ij}(p)\, v^i v^j}\).