Floral meristems and shoot apical meristems (SAMs) are homologous, self-maintaining stem cell systems. Unlike SAMs, floral meristems are determinate, and stem cell maintenance is abolished once all floral organs are initiated. To investigate the underlying regulatory mechanisms, we analyzed the interactions between WUSCHEL (WUS), which specifies stem cell identity, and AGAMOUS (AG), which is required for floral determinacy. Our results show that repression of WUS by AG is essential for terminating the floral meristem and that WUS can induce AG expression in developing flowers. Together, this suggests that floral determinacy depends on a negative autoregulatory mechanism involving WUS and AG, which terminates stem cell maintenance.

A multichannel non-linear frequency compression algorithm was evaluated in comparison to conventional amplification hearing aids using a test of speech understanding in noise (Oldenburger Satztest-OLSA) and subjective questionnaires. The new algorithm compresses frequencies above a pre-calculated cut off frequency and shifts them to a lower frequency range, thereby providing high-frequency audibility. Low-frequencies, below the compression cut off frequency, are amplified normally. This algorithm is called SoundRecover (SR). In this study, 11 experienced hearing aid users with a severe to profound sensorineural hearing loss were tested. Seven subjects showed enhanced levels of understanding in noise (OLSA) using frequency compression. However, 4 out of the 11 subjects could not benefit from the high-frequency gain. Evaluation using questionnaires demonstrated an increased level of satisfaction after 2 months of experimental devices wearing (p = 0.08) and after 4 months of wearing (p = 0.09), respectively, compared to conventional hearing instruments.

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Published evidence and clinical experience support early diagnosis and treatment. Wherever feasible, hearing aid provision before or at the end of the first year of life is recommended for children with UHL. What is Known: • Almost 30 years ago, poor academic performance was reported in children with unilateral hearing loss (UHL). • Despite improvements in treatment options, it is traditionally held that unilateral hearing is the minimum requirement for adequate speech development and hearing aid provision is unnecessary. What is New: • Academic and behavioral deficits in children with UHL may be mediated by deficiencies in the default mode network. • Published evidence supports the recommendation for hearing aid provision before or at the end of the first year of life in children with UHL.