82 research outputs found
Inductive and Transductive Few-Shot Video Classification via Appearance and Temporal Alignments
We present a novel method for few-shot video classification, which performs
appearance and temporal alignments. In particular, given a pair of query and
support videos, we conduct appearance alignment via frame-level feature
matching to achieve the appearance similarity score between the videos, while
utilizing temporal order-preserving priors for obtaining the temporal
similarity score between the videos. Moreover, we introduce a few-shot video
classification framework that leverages the above appearance and temporal
similarity scores across multiple steps, namely prototype-based training and
testing as well as inductive and transductive prototype refinement. To the best
of our knowledge, our work is the first to explore transductive few-shot video
classification. Extensive experiments on both Kinetics and Something-Something
V2 datasets show that both appearance and temporal alignments are crucial for
datasets with temporal order sensitivity such as Something-Something V2. Our
approach achieves similar or better results than previous methods on both
datasets. Our code is available at https://github.com/VinAIResearch/fsvc-ata.Comment: Accepted to ECCV 202
TISE: Bag of Metrics for Text-to-Image Synthesis Evaluation
In this paper, we conduct a study on the state-of-the-art methods for
text-to-image synthesis and propose a framework to evaluate these methods. We
consider syntheses where an image contains a single or multiple objects. Our
study outlines several issues in the current evaluation pipeline: (i) for image
quality assessment, a commonly used metric, e.g., Inception Score (IS), is
often either miscalibrated for the single-object case or misused for the
multi-object case; (ii) for text relevance and object accuracy assessment,
there is an overfitting phenomenon in the existing R-precision (RP) and
Semantic Object Accuracy (SOA) metrics, respectively; (iii) for multi-object
case, many vital factors for evaluation, e.g., object fidelity, positional
alignment, counting alignment, are largely dismissed; (iv) the ranking of the
methods based on current metrics is highly inconsistent with real images. To
overcome these issues, we propose a combined set of existing and new metrics to
systematically evaluate the methods. For existing metrics, we offer an improved
version of IS named IS* by using temperature scaling to calibrate the
confidence of the classifier used by IS; we also propose a solution to mitigate
the overfitting issues of RP and SOA. For new metrics, we develop counting
alignment, positional alignment, object-centric IS, and object-centric FID
metrics for evaluating the multi-object case. We show that benchmarking with
our bag of metrics results in a highly consistent ranking among existing
methods that is well-aligned with human evaluation. As a by-product, we create
AttnGAN++, a simple but strong baseline for the benchmark by stabilizing the
training of AttnGAN using spectral normalization. We also release our toolbox,
so-called TISE, for advocating fair and consistent evaluation of text-to-image
models.Comment: Accepted to ECCV 2022; TISE toolbox is available at
https://github.com/VinAIResearch/tise-toolbo
COLOR MAPPING FOR CAMERA-BASED COLOR CALIBRATION AND COLOR TRANSFER
Ph.DDOCTOR OF PHILOSOPH
HyperCUT: Video Sequence from a Single Blurry Image using Unsupervised Ordering
We consider the challenging task of training models for image-to-video
deblurring, which aims to recover a sequence of sharp images corresponding to a
given blurry image input. A critical issue disturbing the training of an
image-to-video model is the ambiguity of the frame ordering since both the
forward and backward sequences are plausible solutions. This paper proposes an
effective self-supervised ordering scheme that allows training high-quality
image-to-video deblurring models. Unlike previous methods that rely on
order-invariant losses, we assign an explicit order for each video sequence,
thus avoiding the order-ambiguity issue. Specifically, we map each video
sequence to a vector in a latent high-dimensional space so that there exists a
hyperplane such that for every video sequence, the vectors extracted from it
and its reversed sequence are on different sides of the hyperplane. The side of
the vectors will be used to define the order of the corresponding sequence.
Last but not least, we propose a real-image dataset for the image-to-video
deblurring problem that covers a variety of popular domains, including face,
hand, and street. Extensive experimental results confirm the effectiveness of
our method. Code and data are available at
https://github.com/VinAIResearch/HyperCUT.gitComment: Accepted to CVPR 202
A Multi-Center Randomised Controlled Trial of Gatifloxacin versus Azithromycin for the Treatment of Uncomplicated Typhoid Fever in Children and Adults in Vietnam
BACKGROUND: Drug resistant typhoid fever is a major clinical problem globally. Many of the first line antibiotics, including the older generation fluoroquinolones, ciprofloxacin and ofloxacin, are failing. OBJECTIVES: We performed a randomised controlled trial to compare the efficacy and safety of gatifloxacin (10 mg/kg/day) versus azithromycin (20 mg/kg/day) as a once daily oral dose for 7 days for the treatment of uncomplicated typhoid fever in children and adults in Vietnam. METHODS: An open-label multi-centre randomised trial with pre-specified per protocol analysis and intention to treat analysis was conducted. The primary outcome was fever clearance time, the secondary outcome was overall treatment failure (clinical or microbiological failure, development of typhoid fever-related complications, relapse or faecal carriage of S. typhi). PRINCIPAL FINDINGS: We enrolled 358 children and adults with suspected typhoid fever. There was no death in the study. 287 patients had blood culture confirmed typhoid fever, 145 patients received gatifloxacin and 142 patients received azithromycin. The median FCT was 106 hours in both treatment arms (95% Confidence Interval [CI]; 94-118 hours for gatifloxacin versus 88-112 hours for azithromycin), (logrank test p = 0.984, HR [95% CI] = 1.0 [0.80-1.26]). Overall treatment failure occurred in 13/145 (9%) patients in the gatifloxacin group and 13/140 (9.3%) patients in the azithromycin group, (logrank test p = 0.854, HR [95% CI] = 0.93 [0.43-2.0]). 96% (254/263) of the Salmonella enterica serovar Typhi isolates were resistant to nalidixic acid and 58% (153/263) were multidrug resistant. CONCLUSIONS: Both antibiotics showed an excellent efficacy and safety profile. Both gatifloxacin and azithromycin can be recommended for the treatment of typhoid fever particularly in regions with high rates of multidrug and nalidixic acid resistance. The cost of a 7-day treatment course of gatifloxacin is approximately one third of the cost of azithromycin in Vietnam. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN67946944
HOXB13 promotes androgen independent growth of LNCaP prostate cancer cells by the activation of E2F signaling
<p>Abstract</p> <p>Background</p> <p>Androgen signaling plays a critical role in the development of prostate cancer and its progression. However, androgen-independent prostate cancer cells emerge after hormone ablation therapy, resulting in significant clinical problems. We have previously demonstrated that the HOXB13 homeodomain protein functions as a prostate cancer cell growth suppressor by inhibiting androgen-mediated signals. However, the role of the HOXB13 in androgen-independent growth of prostate cancer cells remains unexplained.</p> <p>Results</p> <p>In this report, we first demonstrated that HOXB13 was highly overexpressed in hormone-refractory tumors compared to tumors without prostate-specific antigen after initial treatment. Functionally, in an androgen-free environment minimal induction of HOXB13 in LNCaP prostate cancer cells, to the level of the normal prostate, markedly promoted cell proliferation while suppression inhibited cell proliferation. The HOXB13-mediated cell growth promotion in the absence of androgen, appears to be mainly accomplished through the activation of RB-E2F signaling by inhibiting the expression of the p21<sup>waf </sup>tumor suppressor. Indeed, forced expression of HOXB13 dramatically decreased expression of p21<sup>waf</sup>; this inhibition largely affected HOXB13-mediated promotion of E2F signaling.</p> <p>Conclusions</p> <p>Taken together, the results of this study demonstrated the presence of a novel pathway that helps understand androgen-independent survival of prostate cancer cells. These findings suggest that upregulation of HOXB13 is associated with an additive growth advantage of prostate cancer cells in the absence of or low androgen concentrations, by the regulation of p21-mediated E2F signaling.</p
Clinically and microbiologically derived azithromycin susceptibility breakpoints for Salmonella enterica serovars Typhi and Paratyphi A.
Azithromycin is an effective treatment for uncomplicated infections with Salmonella enterica serovar Typhi and serovar Paratyphi A (enteric fever), but there are no clinically validated MIC and disk zone size interpretative guidelines. We studied individual patient data from three randomized controlled trials (RCTs) of antimicrobial treatment in enteric fever in Vietnam, with azithromycin used in one treatment arm, to determine the relationship between azithromycin treatment response and the azithromycin MIC of the infecting isolate. We additionally compared the azithromycin MIC and the disk susceptibility zone sizes of 1,640 S. Typhi and S. Paratyphi A clinical isolates collected from seven Asian countries. In the RCTs, 214 patients who were treated with azithromycin at a dose of 10 to 20 mg/ml for 5 to 7 days were analyzed. Treatment was successful in 195 of 214 (91%) patients, with no significant difference in response (cure rate, fever clearance time) with MICs ranging from 4 to 16 μg/ml. The proportion of Asian enteric fever isolates with an MIC of ≤ 16 μg/ml was 1,452/1,460 (99.5%; 95% confidence interval [CI], 98.9 to 99.7) for S. Typhi and 207/240 (86.3%; 95% CI, 81.2 to 90.3) (P 16 μg/ml and to determine MIC and disk breakpoints for S. Paratyphi A
Atypical Enteropathogenic Escherichia coli Infection and Prolonged Diarrhea in Children
Infection of children with atypical EPEC is associated with prolonged diarrhea
Differential CARM1 expression in prostate and colorectal cancers
<p>Abstract</p> <p>Background</p> <p>Coactivator-associated arginine methyltransferase 1 (CARM1) functions as a transcriptional coactivator of androgen receptor (AR)-mediated signaling. Correspondingly, overexpression of CARM1 has been associated with the development of prostate cancer (PCa) and its progression to androgen-independent PCa. In our preliminary study, however, the promoting effects of CARM1, with regard to androgen-stimulated AR target gene expression were minimal. These results suggested that the AR target gene expression associated with CARM1 may result primarily from non-hormone dependent activity. The goal of this study was to confirm the pattern of expression of CARM1 in human tumors and determine the mechanism of action in CARM1 overexpressed tumors.</p> <p>Methods</p> <p>Tissue microarray was used to determine the pattern of expression of CARM1 in human cancers by immunohistochemistry. CARM1 expression was also evaluated in prostate and colorectal surgical specimens and the clinical records of all cases were reviewed. In addition, a reporter transcription assay using the prostate-specific antigen (PSA) promoter was used to identify the signaling pathways involved in non-hormone-mediated signal activation associated with CARM1.</p> <p>Results</p> <p>The tissue microarray showed that CARM1 was particularly overexpressed in the colorectal cancers while CARM1 expression was not prevalent in the prostate and breast cancers. Further studies using surgical specimens demonstrated that CARM1 was highly overexpressed in 75% of colorectal cancers (49 out of 65) but not in the androgen-independent PCa. In addition, CARM1's coactivating effect on the entire PSA promoter was very limited in both androgen-dependent and androgen-independent PCa cells. These results suggest that there are other factors associated with CARM1 expression in PSA regulation. Indeed, CARM1 significantly regulated both p53 and NF-κB target gene transcription.</p> <p>Conclusions</p> <p>The results of this study suggest that, in addition to its role in activation of steroid receptors, CARM1 functions as a transcriptional modulator by altering the activity of many transcriptional factors, especially with regard to androgen independent PCa and colorectal cancers.</p
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