The fundamental group of \(X\) at \(x_0\) is \[\pi_1(X, x_0) \;:=\; \bigl\{[\gamma] \mid \gamma \text{ is a loop based at } x_0\bigr\}\] equipped with the group operation of concatenation: \[[\gamma] \cdot [\delta] := [\gamma * \delta], \qquad (\gamma * \delta)(s) := \begin{cases} \gamma(2s) & s \in [0,\tfrac{1}{2}] \\ \delta(2s-1) & s \in [\tfrac{1}{2},1] \end{cases}\] The identity element is the class of the constant loop \([c_{x_0}]\), and the inverse of \([\gamma]\) is \([\bar\gamma]\) where \(\bar\gamma(s) := \gamma(1-s)\).
Nature, Published online: 25 February 2026; doi:10.1038/s41586-026-10142-1
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尽管去年11月底，TransCon-CNP遭到了FDA的延迟审批，但此次推迟并非因疗效或安全性问题，而是FDA要求提交PMR相关信息，这也意味着该药离上市仅一步之遥。，这一点在体育直播中也有详细论述
input = input[:index] + chr(char) + input[index:]，推荐阅读搜狗输入法2026获取更多信息
«Атака американско-сионистских террористов на территорию аэропорта Мехрабад в Тегеране», — сказано в публикации.