2,929 research outputs found
Energy Spectrum Extraction and Optimal Imaging via Dual-Energy Material Decomposition
Inferior soft-tissue contrast resolution is a major limitation of current CT
scanners. The aim of the study is to improve the contrast resolution of CT
scanners using dual-energy acquisition. Based on dual-energy material
decomposition, the proposed method starts with extracting the outgoing energy
spectrum by polychromatic forward projecting the material-selective images. The
extracted spectrum is then reweighted to boost the soft-tissue contrast. A
simulated water cylinder phantom with inserts that contain a series of six
solutions of varying iodine concentration (range, 0-20 mg/mL) is used to
evaluate the proposed method. Results show the root mean square error (RMSE)
and mean energy difference between the extracted energy spectrum and the
spectrum acquired using an energy-resolved photon counting detector(PCD), are
0.044 and 0.01 keV, respectively. Compared to the method using the standard
energy-integrating detectors, dose normalized contrast-to-noise ratio (CNRD)
for the proposed method are improved from 1 to 2.15 and from 1 to 1.88 for the
8 mg/mL and 16 mg/mL iodine concentration inserts, respectively. The results
show CT image reconstructed using the proposed method is superior to the image
reconstructed using the standard method that using an energy-integrating
detector.Comment: 4 pages, 4 figures in The 2015 IEEE Nuclear Science Symposium and
Medical Imaging Conference Recor
Exploiting CLIP for Zero-shot HOI Detection Requires Knowledge Distillation at Multiple Levels
In this paper, we investigate the task of zero-shot human-object interaction
(HOI) detection, a novel paradigm for identifying HOIs without the need for
task-specific annotations. To address this challenging task, we employ CLIP, a
large-scale pre-trained vision-language model (VLM), for knowledge distillation
on multiple levels. Specifically, we design a multi-branch neural network that
leverages CLIP for learning HOI representations at various levels, including
global images, local union regions encompassing human-object pairs, and
individual instances of humans or objects. To train our model, CLIP is utilized
to generate HOI scores for both global images and local union regions that
serve as supervision signals. The extensive experiments demonstrate the
effectiveness of our novel multi-level CLIP knowledge integration strategy.
Notably, the model achieves strong performance, which is even comparable with
some fully-supervised and weakly-supervised methods on the public HICO-DET
benchmark
BH3 mimetic ABT-737 sensitizes colorectal cancer cells to ixazomib through MCL-1 downregulation and autophagy inhibition.
The proteasome inhibitor MLN9708 is an orally administered drug that is hydrolyzed into its active form, MLN2238 (ixazomib). Compared with Bortezomib, MLN2238 has a shorter proteasome dissociation half-life and a lower incidence and severity of peripheral neuropathy, which makes it an attractive candidate for colorectal cancer treatment. In the present study, we observed that MLN2238 induced autophagy, as evidenced by conversion of the autophagosomal marker LC3 from LC3I to LC3II, in colorectal cancer cell lines. Mcl-1, an anti-apoptotic Bcl-2 family protein, was markedly elevated after treating a colorectal cancer cell line with MLN2238. We proved that inhibiting Mcl-1 expression enhances MLN2238 induced apoptosis and negatively regulates autophagy. Co-administration of BH3 mimetic ABT-737 with MLN2238 synergistically kills colorectal cancer cells through MCL-1 neutralization and autophagy inhibition. Furthermore, the synergistic killing effect of the combination therapy is correlated with P53 status in colorectal cancer. These data highlight that the combination of ABT-737 with MLN9708 is a promising therapeutic strategy for human colorectal cancer
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