9-Ethyl-3-(2-methyl­benzo­yl)-9H-carbazole

In the title compound, C22H19NO, the dihedral angle between the benzene ring and the carbazole ring system 77.1 (1)°.. The crystal structure is stabilized by inter­molecular aromatic π–π inter­actions between the benzene ring and the pyrrole ring of the carbazole system of neighbouring mol­ecules [centroid–centroid distance = 3.617 (4) Å]. In addition, the crystal structure exhibits a weak inter­molecular C—H⋯π inter­action

1-[9-Ethyl-6-(2-methyl­benzo­yl)-9H-carbazol-3-yl]ethanone

In the title compound, C24H21NO2, the pendant benzene ring is inclined at a dihedral angle of 86.66 (18)° with respect to the adjacent aromatic ring of the carbozole unit. In the crystal structure, symmetry-related mol­ecules are linked via C—H⋯O and C—H⋯π inter­actions

AdaptSSR: Pre-training User Model with Augmentation-Adaptive Self-Supervised Ranking

User modeling, which aims to capture users' characteristics or interests, heavily relies on task-specific labeled data and suffers from the data sparsity issue. Several recent studies tackled this problem by pre-training the user model on massive user behavior sequences with a contrastive learning task. Generally, these methods assume different views of the same behavior sequence constructed via data augmentation are semantically consistent, i.e., reflecting similar characteristics or interests of the user, and thus maximizing their agreement in the feature space. However, due to the diverse interests and heavy noise in user behaviors, existing augmentation methods tend to lose certain characteristics of the user or introduce noisy behaviors. Thus, forcing the user model to directly maximize the similarity between the augmented views may result in a negative transfer. To this end, we propose to replace the contrastive learning task with a new pretext task: Augmentation-Adaptive SelfSupervised Ranking (AdaptSSR), which alleviates the requirement of semantic consistency between the augmented views while pre-training a discriminative user model. Specifically, we adopt a multiple pairwise ranking loss which trains the user model to capture the similarity orders between the implicitly augmented view, the explicitly augmented view, and views from other users. We further employ an in-batch hard negative sampling strategy to facilitate model training. Moreover, considering the distinct impacts of data augmentation on different behavior sequences, we design an augmentation-adaptive fusion mechanism to automatically adjust the similarity order constraint applied to each sample based on the estimated similarity between the augmented views. Extensive experiments on both public and industrial datasets with six downstream tasks verify the effectiveness of AdaptSSR.Comment: Accepted by NeurIPS 202

The First Successful Transapical Aortic Valve Implant in Korea

Transcatheter aortic valve implantation is an alternative to open heart surgery in high risk patients with severe aortic stenosis. High mortality and complications related to cardiopulmonary bypass for conventional open heart surgery can be avoided with this new less invasive technique. In case of concomitant severe arterial disease, the transapical approach is recommended rather than transfemoral access. An 80-yr-old man with symptomatic aortic stenosis and who had very high surgical risk factors such as diabetes mellitus, hypertension, a history of stroke, bronchial asthma including poor pulmonary function and hepatocellular carcinoma was treated with a transapical aortic valve replacement. The expected mortality in this patient was 25.4% by Euroscore if we performed the conventional aortic valve surgery. The patient was discharged and was well at the 45 follow-up days. We report the first case of successful transcatheter transapical aortic valve implantation which is available recently in Korea

Numerical investigation of gas migration behaviour in saturated bentonite with consideration of temperature

Gas migration behaviour in saturated, compacted bentonite, especially under rigid-boundary conditions, is controversial. Gas breakthrough phenomena, observed under higher pressure gradient conditions in laboratory experiments, are described in literatures by adopting visco-capillary or dilatancy-controlled flow concept. Since, under rigid-boundary conditions, volumetric expansion is restricted and/or water dissipation is not detected, these concepts cannot be implemented satisfactorily. Instead, a diffusion and solubility-controlled (DSC) flow concept was previously found to be adequate for describing the behaviours at lower temperatures (20 °C). The DSC concept describes gas breakthrough as a function of gas solubility. Breakthrough occurs when concentration of dissolved gas reaches or surpasses the solubility limit in the entire specimen. In this work, the DSC flow concept is applied to validate gas migration and breakthrough experiments conducted at higher temperatures, e.g. 40 and 60 °C. Good agreements are observed between the experimental and predicted results, suggesting that the DSC flow concept can be applied to describe gas migration behaviour satisfactorily in rigidly confined saturated bentonites (under constant volume conditions) for various temperature regimes. Results also show that helium dissolution and diffusion processes in saturated bentonite are sensitive to test temperature and pressure conditions. The processes become more stable with increasing gas injection pressure and ambient temperature