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Sensory System Alterations Following Occupational Exposure to Chemicals
Published in Lucio G. Costa, Luigi Manzo, Occupatinal Neurotoxicology, 2020
More recently, quantitative histological, ultrastructural, biochemical and ERG studies have shown that moderate level lead exposure only during adulthood (BPb: 59 μg/dl) produces selective rod photoreceptor deficits and apoptotic cell death in rods and bipolar cells.108 These results are consistent with neurobehavioral and ERG studies conducted in lead-exposed workers (vide supra) and similar to studies conducted in developing rats exposed to lead only during development.125-126 That is, the rod-mediated, but not cone-mediated, ERG showed decreases in a-wave and b-wave amplitude, sensitivity, critical flicker fusion threshold and dark adaptation. These results suggest that lead produces similar functional alterations in the mature and developing visual system: albeit with different degrees of sensitivity and severity.
A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate
Published in Journal of Information Display, 2023
Jung Chul Kim, I. Sak Lee, Hyung Tae Kim, Jong Bin An, Jae Sung Kim, Juhn Suk Yoo, Han Wook Hwang, Hyun Chul Choi, Yong Min Ha, Hyun Jae Kim
Second step (emission period): Figure 1 shows that after VDATA programming, stress applied to the D-TFT changes the TFT I-V characteristics from IDS_(2) to IDS_(3) because of D-TFT hysteresis, changing the luminance. The transient luminance change caused by D-TFT hysteresis does not create a visible flicker at conventional frame rates (e.g. 60 Hz) because the perceived luminance fluctuation is well below the flicker fusion threshold [22]. Under low-frame rate driving, however, it is critical to minimize the luminance fluctuation over time because the sensitivity of humans to flicker increases greatly from 10 to 15 Hz [23]. As might be expected, the larger the hysteresis, the greater the luminance fluctuation and the more perceptible the flicker under low-frame rate driving. For this reason, low-frame rate driving requires that the leakage currents of the switching TFTs are low, and the hysteresis of the D-TFT is small. However, hysteresis is an intrinsic feature of an LTPS TFT [24]. Therefore, for low-frame rate driving of an LTPO TFT-based AMOLED display, a new driving scheme that can compensate for D-TFT hysteresis is required.