1,565 research outputs found
A Reverse Hierarchy Model for Predicting Eye Fixations
A number of psychological and physiological evidences suggest that early
visual attention works in a coarse-to-fine way, which lays a basis for the
reverse hierarchy theory (RHT). This theory states that attention propagates
from the top level of the visual hierarchy that processes gist and abstract
information of input, to the bottom level that processes local details.
Inspired by the theory, we develop a computational model for saliency detection
in images. First, the original image is downsampled to different scales to
constitute a pyramid. Then, saliency on each layer is obtained by image
super-resolution reconstruction from the layer above, which is defined as
unpredictability from this coarse-to-fine reconstruction. Finally, saliency on
each layer of the pyramid is fused into stochastic fixations through a
probabilistic model, where attention initiates from the top layer and
propagates downward through the pyramid. Extensive experiments on two standard
eye-tracking datasets show that the proposed method can achieve competitive
results with state-of-the-art models.Comment: CVPR 2014, 27th IEEE Conference on Computer Vision and Pattern
Recognition (CVPR). CVPR 201
Meta Semantics: Towards better natural language understanding and reasoning
Natural language understanding is one of the most challenging topics in
artificial intelligence. Deep neural network methods, particularly large
language module (LLM) methods such as ChatGPT and GPT-3, have powerful
flexibility to adopt informal text but are weak on logical deduction and suffer
from the out-of-vocabulary (OOV) problem. On the other hand, rule-based methods
such as Mathematica, Semantic web, and Lean, are excellent in reasoning but
cannot handle the complex and changeable informal text. Inspired by pragmatics
and structuralism, we propose two strategies to solve the OOV problem and a
semantic model for better natural language understanding and reasoning.Comment: 10 pages, 8 figures, 2 table
Sulfanilamide benzotriazole tetrazole inhibits neuronal apoptosis in neonatal rats by targeting JNK and p38 MAPK pathways
Purpose: To investigate the neuroprotective effect of sulfanilamide benzotriazole tetrazole (SBT) in neonatal rats exposed to isoflurane, and also to elucidate the underlying mechanism.
Methods: Rat pups (n = 60) were randomly assigned to six groups of 10 pups each: normal control group, negative control group, 5 mg/kg SBT group, 10 mg/kg SBT group, 15 mg/kg SBT group, and 20 mg/kg SBT group. With exception of normal control group, pups were exposed to isoflurane (0.75 %) for 6 h on postnatal day 7. The negative control group was not treated, while pups in the four treatment groups received 5, 10, 15 and 20 mg/kg SBT, respectively, 1 h after exposure to anaesthesia. TUNEL assay was used to determine the extent of apoptosis in cornu ammonis area-1 (CA-1), cornu ammonis area-3 (CA-3) and dentate gyrus of rat hippocampal tissues. Expressions of apoptotic and anti-apoptotic proteins were determined using Western blotting. Evaluation of learning and memorizing ability was done using Morris water maze test.
Results: Isoflurane significantly increased the extent of apoptosis in CA-1, CA-3 and dentate gyrus of rat hippocampal tissues (p < 0.05). However, treatment with SBT significantly and dose-dependently reduced neuronal apoptosis (p < 0.05). The expression of caspase 3 was significantly upregulated by isoflurane, but was significantly and dose-dependently down-regulated by SBT (p < 0.05). Isoflurane significantly increased Bax expression, and decreased the expression of bcl-2 (p < 0.05). The effects of isoflurane on the expression of these proteins were significantly and dose-dependently reversed by SBT (p < 0.05). The expression of bcl xL in rat hippocampal tissues was significantly down-regulated by isoflurane, but was significantly and dose-dependently upregulated by SBT (p < 0.05). The escape latency of pups was significantly higher in negative control group than in normal control group, but SBT treatment significantly and dose-dependently reversed this trend (p < 0.05).
Conclusion: These results suggest that SBT prevents neuronal apoptosis, and improves the ability to learn and memorize in neonatal rats exposed to isoflurane via regulation of apoptotic, JNK and p38 MAPK protein expressions
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