Weakly-Supervised Action Localization by Hierarchically-structured Latent Attention Modeling

Weakly-supervised action localization aims to recognize and localize action instancese in untrimmed videos with only video-level labels. Most existing models rely on multiple instance learning(MIL), where the predictions of unlabeled instances are supervised by classifying labeled bags. The MIL-based methods are relatively well studied with cogent performance achieved on classification but not on localization. Generally, they locate temporal regions by the video-level classification but overlook the temporal variations of feature semantics. To address this problem, we propose a novel attention-based hierarchically-structured latent model to learn the temporal variations of feature semantics. Specifically, our model entails two components, the first is an unsupervised change-points detection module that detects change-points by learning the latent representations of video features in a temporal hierarchy based on their rates of change, and the second is an attention-based classification model that selects the change-points of the foreground as the boundaries. To evaluate the effectiveness of our model, we conduct extensive experiments on two benchmark datasets, THUMOS-14 and ActivityNet-v1.3. The experiments show that our method outperforms current state-of-the-art methods, and even achieves comparable performance with fully-supervised methods.Comment: Accepted to ICCV 2023. arXiv admin note: text overlap with arXiv:2203.15187, arXiv:2003.12424, arXiv:2104.02967 by other author

Fetal Isolated Anomalous Origin of Right Pulmonary Artery from Aorta

Abstract The anomalous origin of a branch pulmonary artery from the aorta (AOPA) is characterized by the anomalous origin of one of the branch pulmonary arteries (PA) from the ascending aorta and a normal origin of the other PA from main PA. AOPA is an extremely rare cardiac malformation. Few studies have reported fetal anomalous origin of PA from aorta with other malformation. We report a case of isolated distal anomalous origin of the right PA from the aorta that was diagnosed by fetal echocardiography at 25 weeks' of gestation. Tracing the course of PA branches is important to make diagnosis

Contrast-enhanced ultrasound of small cell carcinoma in urinary bladder: a case report and review of literature

Abstract Background Small cell carcinoma of the urinary bladder (SCCB) is a relatively rare malignant bladder tumor, and few reports have investigated the microvasculature of SCCB imaged using contrast-enhanced ultrasound (CEUS). Case presentation A 63-year-old female was admitted to our hospital after experiencing painless gross hematuria for one week. The gray-scale ultrasound (US) demonstrated a 4.8 × 3.4 × 3.6-cm3 hypoechoic mass in the apex of the urinary bladder with a wide base and an irregular surface; the mass did not move with changes in body position. Color Doppler flow imaging (CDFI) showed rich blood flow in the mass. CEUS with low mechanical index (MI) of 0.06 confirmed a highly enhanced 5.0 × 3.3 × 3.8 cm3 mass within the bladder at the apex wall. The time-intensity curves (TICs) showed a wash-in time of 10 s, a time to peak (TTP) of 33 s, a signal intensity (SI) of 62.7% and a wash-out time > 60 s. Finally, the transurethral resection of the bladder tumor (TURBT) was performed, and the pathological examination proved the diagnosis of SCCB. Conclusion CEUS can provide valuable information related to the rich microvasculature of SCCB, which may be helpful in its diagnosis

The role of robotic surgery in neurological cases: A systematic review on brain and spine applications

The application of robotic surgery technologies in neurological surgeries resulted in some advantages compared to traditional surgeries, including higher accuracy and dexterity enhancement. Its success in various surgical fields, especially in urology, cardiology, and gynecology surgeries was reported in previous studies, and similar advantages in neurological surgeries are expected. Surgeries in the central nervous system with the pathology of millimeters through small working channels around vital tissue need especially high precision. Applying robotic surgery is therefore an interesting dilemma for these situations. This article reviews various studies published on the application of brain and spine robotic surgery and discusses the current application of robotic technology in neurological cases

Synthesis of Azole-Enriched Cyclic Peptides by A Clean Solid-Phase-Based Cyclization-Cleavage Strategy

Naturally occurring azole-enriched cyclic peptides have broad biological and pharmacological activities. Previous synthetic efforts have mainly concentrated on the preparation of individual target molecules in solution phase. A solid-phase-based cyclitive cleavage strategy was deployed here for efficient library synthesis of azole cyclopeptide derivatives, which is part of our continuous efforts for the characterization of potent modulators of multidrug resistance efflux proteins. Procedures were optimized to afford the azole cyclopeptides at high yield and purity, eliminating the need for any chromatographic purification steps. This development is ideal for high throughput library synthesis and screening and will facilitate the ultimate discovery of novel azole cyclopeptides with potent biological activities

Cholate-Based Synthesis of Size-Tunable Cage Compounds

We describe cholate-based cage amphiphiles with a unique architecture that combines elements of structural rigidity and flexibility. The cage compounds are built by extending and bridging three polar chains underneath the concave steroid rings of cholate and capping with another rigid, symmetrically trifunctionalized cyanuric acid moiety. The connecting chains are varied to include, for instance, oligo­(ethylene glycol) or chains containing 1,2,3-triazole units to present flexibility in the chemical and structural space and potentially deliver functional molecules for molecular recognition applications