Morphology in the total electron content under geomagnetic disturbed conditions: results from global ionosphere maps

International audienceUsing 8-year global ionosphere maps (GIMs) of TEC products from the Jet Propulsion Laboratory (JPL), we make a statistical study on the morphology of the global ionospheric behaviors with respect to the geomagnetic disturbances. Results show that the behaviors of TEC during geomagnetic storm present clear seasonal and local time variations under geomagnetic control in a similar way as those of NmF2 (Field and Rishbeth, 1997). A negative phase of TEC occurs with high probability in the summer hemisphere and most prominent near the geomagnetic poles, while a positive phase is obvious in the winter hemisphere and in the far pole region. A negative storm effect toward lower latitudes tends to occur from post-midnight to the morning sector and recedes to high latitude in the afternoon. A positive storm effect is separated by geomagnetic latitudes and magnetic local time. Furthermore, ionospheric responses at different local time sectors with respect to the storm commencement shows very different developing processes corresponding to the evolution of the geomagnetic storm. A daytime positive storm effect is shown to be more prominent in the American region than those in the Asian and European regions, which may suggest a longitudinal effect of the ionospheric storm

Improving Few-shot and Zero-shot Entity Linking with Coarse-to-Fine Lexicon-based Retriever

Few-shot and zero-shot entity linking focus on the tail and emerging entities, which are more challenging but closer to real-world scenarios. The mainstream method is the ''retrieve and rerank'' two-stage framework. In this paper, we propose a coarse-to-fine lexicon-based retriever to retrieve entity candidates in an effective manner, which operates in two layers. The first layer retrieves coarse-grained candidates by leveraging entity names, while the second layer narrows down the search to fine-grained candidates within the coarse-grained ones. In addition, this second layer utilizes entity descriptions to effectively disambiguate tail or new entities that share names with existing popular entities. Experimental results indicate that our approach can obtain superior performance without requiring extensive finetuning in the retrieval stage. Notably, our approach ranks the 1st in NLPCC 2023 Shared Task 6 on Chinese Few-shot and Zero-shot Entity Linking.Comment: Accepted to NLPCC202

Safety and efficacy of early radiofrequency catheter ablation in patients with paroxysmal atrial fibrillation complicated with amiodarone-induced thyrotoxicosis

Background: Amiodarone is an antiarrhythmic drug that is frequently used to control atrial fibrillation (AF). Many patients with AF are afraid of the risk of ablation and take amiodar­one, some patients develop amiodarone-induced thyrotoxicosis (AIT). The purpose of the study was to investigate the safety and efficacy of early radiofrequency catheter ablation in patients with paroxysmal AF complicated with AIT. Methods: From the 146 consecutive patients with paroxysmal AF who had been treated with amiodarone and underwent 3-dimensional mapping system guided circumferential pulmonary vein isolation (PVI) at our center from January 2013 to June 2014, 20 had developed AIT. Thirty controls with normal thyroid function and matched for baseline characteristics were selected. Results: Pulmonary vein isolation was completed in all patients without serious complications and with similar procedural (170.60 ± 14.80 vs. 158.18 ± 9.06 min; p = 0.062) and X-ray exposure (16.48 ± 2.15 vs. 15.36 ± 1.57 min; p = 0.058) time in AIT vs. control groups; however, upon coronary sinus catheter pacing (from 300 ms to 200 ms) after intrave­nous isoproterenol administration 30 min post PVI, rates of induction of AF (35% vs. 3.33%; p = 0.005) and of non-pulmonary vein-related atrial tachyarrhythmias (50% vs. 6.67%; p = 0.01) were higher, while those for atrial flutter (15% vs. 3.33%; p = 0.17) and atrial tachycardia (15% vs. 6.67%; p = 0.31) were similar, as was the recovery of conduction of pulmonary vein potential (15% vs. 30%; p = 0.191). In AIT vs. control group, atrial tachyarrhythmia recurrence rate was higher at 3 months (45% vs. 16.67%, p = 0.032) but not between 3 and 12 months (30% vs. 23.33%; p = 0.418) follow-up. Conclusions: Early catheter ablation for paroxysmal AF in patients with AIT appeared safe and effective albeit with higher atrial tachyarrhythmia recurrence rate up to 3 months but not beyond 12 months after PVI relative to controls.

Investigating on Through Glass via Based RF Passives for 3-D Integration

Due to low dielectric loss and low cost, glass is developed as a promising material for advanced interposers in 2.5-D and 3-D integration. In this paper, through glass vias (TGVs) are used to implement inductors for minimal footprint and large quality factor. Based on the proposed physical structure, the impact of various process and design parameters on the electrical characteristics of TGV inductors is investigated with 3-D electromagnetic simulator HFSS. It is observed that TGV inductors have identical inductance and larger quality factor in comparison with their through silicon via counterparts. Using TGV inductors and parallel plate capacitors, a compact 3-D band-pass filter (BPF) is designed and analyzed. Compared with some reported BPFs, the proposed TGV-based circuit has an ultra-compact size and excellent filtering performance

Information Sharing Behavior in Social Commerce Sites: The Differences between Sellers and Non-Sellers

The rise of social media encouraged customers to share information more frequently and to larger extent. Previous work primarily focused on how and why customers share information in online social commerce sites. In the current study, we distinguish between the two types of users: sellers and non-sellers in social commerce sites. Drawing on the goal theory, we empirically examine intrinsic and extrinsic benefits as the key direct antecedents, and explore the moderating role of sellers/non-sellers in the relationship between intrinsic and extrinsic benefits and information sharing behavior. Analyzing survey data (n=1170) in the first phase collected from a popular social commerce site, we found that intention to share information among sellers and non-sellers are indeed different. This study can advance the understandings of information sharing literature by revealing the differences between different types of users. The results offer important and interesting insights to IS research and practice