Purpose: To investigate the retinal responses generated by flash interactions in a recently introduced "global (full-screen) flash" stimulus paradigm to record the multifocal electroretinogram (mfERG).
Methods: Five normal individuals were studied with stimulation combining multifocal (pseudorandom) flashes with interleaved global (periodic, full-screen) flashes. The intensities of the two flashes were independently varied. Two distinct first-order response components were obtained: the mean response to the focal flashes (referred to as the direct response, DR) and the effect of the focal flash on the responses evoked by the global flash (the induced component, IC).
Results: Increasing the global flash luminance reduced DR amplitude and shortened DR implicit time. IC amplitude peaked with a moderate global flash (1.33-2.67 cd.s/m2). With a global flash of the right intensity, a weak focal flash could evoke a considerable IC even when the DR was barely detectable. Moderate global flashes maximized the IC, and its intersubject variability was reduced at lower focal flash luminances. IC topography had a large naso-temporal asymmetry.
Conclusions: While the DR is the average response generated by the local flashes regardless of the context of preceding and following flashes, the IC represents the difference in the global flash response in the presence and absence of the preceding focal flash. As the focal flashes were always preceded by the periodically occurring global flashes, the DR reflects the resulting adapted or desensitized state of the retinal patch. The pure, nonlinear IC is thought to reflect predominantly inner retinal function.
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http://dx.doi.org/10.1007/s00417-004-1072-y | DOI Listing |
Water Res
December 2024
Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 211135, China; Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing 100039, China; Poyang Lake Wetland Research Station, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Jiujiang 332899, China. Electronic address:
Flash drought (FD) events induced by climate change may disrupt the normal hydrological regimes of floodplain lakes and affect the plant-microbe mediated dissimilatory nitrate reduction (DNR), i.e., denitrification, anammox and dissimilatory nitrate reduction to ammonium (DNRA), thus having important consequences for nitrous oxide (NO) emissions and nitrogen (N) retention.
View Article and Find Full Text PDFSci Data
January 2025
University of Southern California, Viterbi School of Engineering, 3737 Watt Way, Powell Hall of Engineering, Los Angeles, CA, 90089, USA.
Soil erosion in North Africa modulates agricultural and urban developments as well as the impacts of flash floods. Existing investigations and associated datasets are mainly performed in localized urban areas, often representing a limited part of a watershed. The above compromises the implementation of mitigation measures for this vast area under accentuating extremes and continuous hydroclimatic fluctuations.
View Article and Find Full Text PDFInvest Ophthalmol Vis Sci
January 2025
School of Psychology and Public Health, La Trobe University, Melbourne, Australia.
Purpose: Prolonged exposure to broadband light with a short-wavelength (blue) or long-wavelength (orange/red) bias is known to impact eye growth and refraction, but the mechanisms underlying this response are unknown. Thus, the present study investigated the effects of broadband blue and orange lights with well-differentiated spectrums on refractive development and global flash electroretinography (gfERG) measures of retinal function in the chick myopia model.
Methods: Chicks were raised for 4 days with monocular negative lenses, or no lens, under blue, orange, or white light.
Polymers (Basel)
December 2024
Green Technology Group, Faculty of Science, Alexandria University, Alexandria 21511, Egypt.
Plastic waste (PW) presents a significant environmental challenge due to its persistent accumulation and harmful effects on ecosystems. According to the United Nations Environment Program (UNEP), global plastic production in 2024 is estimated to reach approximately 500 million tons. Without effective intervention, most of this plastic is expected to become waste, potentially resulting in billions of tons of accumulated PW by 2060.
View Article and Find Full Text PDFPhys Med Biol
January 2025
Research, RaySearch Laboratories, Stockholm, Sweden.
The advent of ultra-high dose rate irradiation, known as FLASH radiation therapy, has shown promising potential in reducing toxicity while maintaining tumor control. However, the clinical translation of these benefits necessitates efficient treatment planning strategies. This study introduces a novel approach to optimize proton therapy for FLASH effects using traveling salesperson problem (TSP) heuristics.
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