We know that there is a cofibration sequence $$S^{4n+1}\xrightarrow{\theta}\Sigma^{4m-1} Q_{n-m} \rightarrow \Sigma^{4m-1} Q_{n-m+1} \rightarrow S^{4n+2}\xrightarrow{\Sigma\theta}\Sigma^{4m} Q_{n-m}.$$ How to show the map $$(\Sigma\theta)^*\colon\widetilde {KSp}^{-2} (\Sigma^{4m} Q_{n-m}) \rightarrow \widetilde {KSp}^{-2} (S^{4n+2})\cong \mathbb{Z}$$ is zero, where $m$ and $n$ are two positive integers such that $m<n$, and $Q_{n-m}$ is the symplectic quasi-projective space of rank $n-m$?
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\overset{#1}\rightarrow, you can use\xrightarrow{#1}(which grows with its argument). Compare, for example, $\overset{\Sigma\theta}\rightarrow$\overset{\Sigma\theta}\rightarrowto $\xrightarrow{\Sigma\theta}$\xrightarrow{\Sigma\theta}. I have edited accordingly. $\endgroup$