* This method is called after frameFinished(), but with an additional
* constraint that it is always called in serial and with an increasing
* \p frameIndex. Parallel data modules need this to serialize their
- * data for downsteam serial modules; AnalysisDataModuleSerial provides
+ * data for downstream serial modules; AnalysisDataModuleSerial provides
* an empty implementation, as there frameFinished() can be used for
* the same purpose.
*/