Resilient neural network training for accelerators with computing errors

—With the advancements of neural networks, customized accelerators are increasingly adopted in massive AI applications. To gain higher energy efficiency or performance, many hardware design optimizations such as near-threshold logic or overclocking can be utilized. In these cases, computing errors may happen and the computing errors are difficult to be captured by conventional training on general purposed processors (GPPs). Applying the offline trained neural network models to the accelerators with errors directly may lead to considerable prediction accuracy loss. To address this problem, we explore the resilience of neural network models and relax the accelerator design constraints to enable aggressive design options. First of all, we propose to train the neural network models using the accelerators’ forward computing results such that the models can learn both the data and the computing errors. In addition, we observe that some of the neural network layers are more sensitive to the computing errors. With this observation, we schedule the most sensitive layer to the attached GPP to reduce the negative influence of the computing errors. According to the experiments, the neural network models obtained from the proposed training outperform the original models significantly when the CNN accelerators are affected by computing errors

Corneal Epithelial Remodeling and Its Effect on Corneal Asphericity after Transepithelial Photorefractive Keratectomy for Myopia

Purpose. To evaluate the changes in epithelial thickness profile following transepithelial photorefractive keratectomy (T-PRK) for myopia and to investigate the effect of epithelial remodeling on corneal asphericity. Methods. Forty-four patients (44 right eyes) who underwent T-PRK were retrospectively evaluated. Epithelial thickness was measured using spectral-domain optical coherence tomography at different corneal zones (central, 2 mm; paracentral, 2–5 mm; and mid-peripheral, 5-6 mm) preoperatively and at 1 week and 1, 3, and 6 months postoperatively. The correlation between the changes in corneal epithelial thickness (ΔCET) and postoperative Q-value changes (ΔQ) was analyzed 6 months postoperatively. Results. Epithelial thickness at 6 months showed a negative meniscus-like lenticular pattern with less central thickening, which increased progressively toward the mid-periphery (3.69±4.2, 5.19±3.8, and 6.23±3.9 μm at the center, paracenter, and mid-periphery, resp., P<0.01). A significant positive relationship was observed between epithelial thickening and ΔQ 6 months postoperatively (r=0.438, 0.580, and 0.504, resp., P<0.01). Conclusions. Significant epithelial thickening was observed after T-PRK and showed a lenticular change with more thickening mid-peripherally, resulting in increased oblateness postoperatively. Epithelial remodeling may modify the epithelial thickness profile after surface ablation refractive surgery for myopia

Immunomodulatory role of estrogen in ischemic stroke: neuroinflammation and effect of sex

Although estrogen is predominantly related to the maintenance of reproductive functioning in females, it mediates various physiological effects in nearly all tissues, especially the central nervous system. Clinical trials have revealed that estrogen, especially 17β-estradiol, can attenuate cerebral damage caused by an ischemic stroke. One mechanism underlying this effect of 17β-estradiol is by modulating the responses of immune cells, indicating its utility as a novel therapeutic strategy for ischemic stroke. The present review summarizes the effect of sex on ischemic stroke progression, the role of estrogen as an immunomodulator in immune reactions, and the potential clinical value of estrogen replacement therapy. The data presented here will help better understand the immunomodulatory function of estrogen and may provide a basis for its novel therapeutic use in ischemic stroke

Identifying veraison process of colored wine grapes in field conditions combining deep learning and image analysis

Acknowledgments This work was supported by the National Key R&D Program Project of China (Grant No. 2019YFD1002500) and Guangxi Key R&D Program Project (Grant No. Gui Ke AB21076001) The authors would like to thank the anonymous reviewers for their helpful comments and suggestions.Peer reviewedPostprin

Development of a mobile application for identification of grapevine (Vitis vinifera L.) cultivars via deep learning

Acknowledgements: The authors would like to express their gratitude to the Teaching Experiment Farm of Ningxia University, for their kind help. This study was supported by the Key R & D projects of Ningxia Hui Autonomous Region (Grant No. 2019BBF02013)Peer reviewedPublisher PD

Target Enzyme-Activated Two-Photon Fluorescent Probes:A Case Study of CYP3A4 Using a Two-Dimensional Design Strategy

The rapid development of fluorescent probes for monitoring target enzymes is still a great challenge owing to the lack of efficient ways to optimize a specific fluorophore. Herein, a practical two-dimensional strategy was designed for the development of an isoform-specific probe for CYP3A4, a key cytochrome P450 isoform responsible for the oxidation of most clinical drugs. In first dimension of the design strategy, a potential two-photon fluorescent substrate (NN) for CYP3A4 was effectively selected using ensemble-based virtual screening. In the second dimension, various substituent groups were introduced into NN to optimize the isoform-selectivity and reactivity. Finally, with ideal selectivity and sensitivity, NEN was successfully applied to the real-time detection of CYP3A4 in living cells and zebrafish. These findings suggested that our strategy is practical for developing an isoform-specific probe for a target enzyme.</p

Altered expression of inflammation-associated molecules in striatum: an implication for sensitivity to heavy ion radiations

Background and objectiveHeavy ion radiation is one of the major hazards astronauts face during space expeditions, adversely affecting the central nervous system. Radiation causes severe damage to sensitive brain regions, especially the striatum, resulting in cognitive impairment and other physiological issues in astronauts. However, the intensity of brain damage and associated underlying molecular pathological mechanisms mediated by heavy ion radiation are still unknown. The present study is aimed to identify the damaging effect of heavy ion radiation on the striatum and associated underlying pathological mechanisms.Materials and methodsTwo parallel cohorts of rats were exposed to radiation in multiple doses and times. Cohort I was exposed to 15 Gy of 12C6+ ions radiation, whereas cohort II was exposed to 3.4 Gy and 8 Gy with 56Fe26+ ions irradiation. Physiological and behavioural tests were performed, followed by 18F-FDG-PET scans, transcriptomics analysis of the striatum, and in-vitro studies to verify the interconnection between immune cells and neurons.ResultsBoth cohorts revealed more persistent striatum dysfunction than other brain regions under heavy ion radiation at multiple doses and time, exposed by physiological, behavioural, and 18F-FDG-PET scans. Transcriptomic analysis revealed that striatum dysfunction is linked with an abnormal immune system. In vitro studies demonstrated that radiation mediated diversified effects on different immune cells and sustained monocyte viability but inhibited its differentiation and migration, leading to chronic neuroinflammation in the striatum and might affect other associated brain regions.ConclusionOur findings suggest that striatum dysfunction under heavy ion radiation activates abnormal immune systems, leading to chronic neuroinflammation and neuronal injury