Fluorescence microscopy has become one of the most widely employed in vivo imaging modalities,enabling the discovery of new biopathological mechanisms.However,the application of fluorescence imaging is often hindered ...Fluorescence microscopy has become one of the most widely employed in vivo imaging modalities,enabling the discovery of new biopathological mechanisms.However,the application of fluorescence imaging is often hindered by signal-to-noise ratio issues owing to inherent noise arising from various systemic and biophysical characteristics.These limitations pose a growing challenge,especially with the desire to elucidate dynamic biomechanisms at previously unreachable rapid speeds.Here,we propose a temporal gradient(TG)-based self-supervised denoising network(TeD)that could enable an unprecedented advance in spatially dynamic fluorescence imaging.Our strategy is predicated on the insight that judicious utilization of spatiotemporal information is more advantageous for denoising predictions.Adopting the TG,which intrinsically embodies spatial dynamic features,enables TeD to prudently focus on spatiotemporal information.We showed that TeD can provide new interpretative opportunities for understanding dynamic fluorescence signals in in vivo imaging of mice,representing cellular flow.Furthermore,we demonstrated that TeD is robust even when fluorescence signals exhibit temporal kinetics without spatial dynamics,as seen in neuronal population imaging.We believe that TeD’s superior performance even with spatially dynamic samples,including the complex behavior of cells or organisms,could make a substantial contribution to various biological studies.展开更多
At present, the main problem faced by ground-based augment system （GBAS） is that though carder smoothing filter and local differential global positioning system （LDGPS） improve the accuracy of the pseudorange by r...At present, the main problem faced by ground-based augment system （GBAS） is that though carder smoothing filter and local differential global positioning system （LDGPS） improve the accuracy of the pseudorange by reducing the noise in it and eliminating almost all the common errors between the user and the reference station, they also cause extra errors on account of the effects of the ionosphere temporal and spatial gradients. Based on the analysis of these errors as well as the smoothing noise, this article suggests a new algorithm to design the optimal Hatch filter, whose smoothing window width varies real-time with the satellite elevation, ionosphere variation, and distance from the user to the reference station. By conducting the positioning process in the GBAS emulation platform for several hours and after its comparison with the performances of traditional Hatch filters, it is found that the errors in the differential correction become smaller and the positioning accuracy gets heightened with this new method.展开更多
Stress gradient hypothesis predicted that facilitative interactions usually increase in intensity and are importance with abiotic stress.By contrast,facilitation may be lost in time,when it involves the growth of bene...Stress gradient hypothesis predicted that facilitative interactions usually increase in intensity and are importance with abiotic stress.By contrast,facilitation may be lost in time,when it involves the growth of benefactors or beneficiaries.Less is known about which response pattern is more common in arid desert.We present an empirical study to explore shrub-annual interactions at the community and individual level along the course of a single growing season in a desert steppe in northwest China.Here the severity of drought stress may increase in time due to uneven precipitation during plant growing season.We assessed growth responses of annuals in understory where two dominant shrubs were removed.Annuals responses showed a switch from weakly positive to more strongly positive beneath Calligonum mongolicum,whereas from positive to negative beneath Nitraria sphaerocarpa during the growing season.Additionally,annual species with contrasting functional traits showed distinct growth responses to canopies removal.There was evidence of an increase in soil moisture below the canopy of shrubs,but a decrease in potential evaporation rate and photosynthetically active radiation,which can partly explain these species-specific responses.We conclude that the balance between competitive and facilitative effects in shrub-annual interactions is not only governed by the severity of stress but also determined by plant traits,such as canopy structure of shrubs and functional traits of their understory annuals.展开更多
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(NRF-RS-2023-00208888 and NRF-RS-2024-00401786)by a Korea Medical Device Development Fund grant funded by the Korean government(Ministry of Science and Information and Communication Technologies,Ministry of Trade,Industry and Energy,Ministry of Health and Welfare,Ministry of Food and Drug Safety)(RS-2023-00254566).
文摘Fluorescence microscopy has become one of the most widely employed in vivo imaging modalities,enabling the discovery of new biopathological mechanisms.However,the application of fluorescence imaging is often hindered by signal-to-noise ratio issues owing to inherent noise arising from various systemic and biophysical characteristics.These limitations pose a growing challenge,especially with the desire to elucidate dynamic biomechanisms at previously unreachable rapid speeds.Here,we propose a temporal gradient(TG)-based self-supervised denoising network(TeD)that could enable an unprecedented advance in spatially dynamic fluorescence imaging.Our strategy is predicated on the insight that judicious utilization of spatiotemporal information is more advantageous for denoising predictions.Adopting the TG,which intrinsically embodies spatial dynamic features,enables TeD to prudently focus on spatiotemporal information.We showed that TeD can provide new interpretative opportunities for understanding dynamic fluorescence signals in in vivo imaging of mice,representing cellular flow.Furthermore,we demonstrated that TeD is robust even when fluorescence signals exhibit temporal kinetics without spatial dynamics,as seen in neuronal population imaging.We believe that TeD’s superior performance even with spatially dynamic samples,including the complex behavior of cells or organisms,could make a substantial contribution to various biological studies.
基金National Natural Science Foundation of China (60672181)National High-tech Research and Development Program (2006AA12A101)
文摘At present, the main problem faced by ground-based augment system （GBAS） is that though carder smoothing filter and local differential global positioning system （LDGPS） improve the accuracy of the pseudorange by reducing the noise in it and eliminating almost all the common errors between the user and the reference station, they also cause extra errors on account of the effects of the ionosphere temporal and spatial gradients. Based on the analysis of these errors as well as the smoothing noise, this article suggests a new algorithm to design the optimal Hatch filter, whose smoothing window width varies real-time with the satellite elevation, ionosphere variation, and distance from the user to the reference station. By conducting the positioning process in the GBAS emulation platform for several hours and after its comparison with the performances of traditional Hatch filters, it is found that the errors in the differential correction become smaller and the positioning accuracy gets heightened with this new method.
基金financial supported by the National Basic Research Program of China (2013CB429903)the National Natural Science Foundation of China (41301603)
文摘Stress gradient hypothesis predicted that facilitative interactions usually increase in intensity and are importance with abiotic stress.By contrast,facilitation may be lost in time,when it involves the growth of benefactors or beneficiaries.Less is known about which response pattern is more common in arid desert.We present an empirical study to explore shrub-annual interactions at the community and individual level along the course of a single growing season in a desert steppe in northwest China.Here the severity of drought stress may increase in time due to uneven precipitation during plant growing season.We assessed growth responses of annuals in understory where two dominant shrubs were removed.Annuals responses showed a switch from weakly positive to more strongly positive beneath Calligonum mongolicum,whereas from positive to negative beneath Nitraria sphaerocarpa during the growing season.Additionally,annual species with contrasting functional traits showed distinct growth responses to canopies removal.There was evidence of an increase in soil moisture below the canopy of shrubs,but a decrease in potential evaporation rate and photosynthetically active radiation,which can partly explain these species-specific responses.We conclude that the balance between competitive and facilitative effects in shrub-annual interactions is not only governed by the severity of stress but also determined by plant traits,such as canopy structure of shrubs and functional traits of their understory annuals.
