Improving Conversational Passage Re-ranking with View Ensemble

This paper presents ConvRerank, a conversational passage re-ranker that employs a newly developed pseudo-labeling approach. Our proposed view-ensemble method enhances the quality of pseudo-labeled data, thus improving the fine-tuning of ConvRerank. Our experimental evaluation on benchmark datasets shows that combining ConvRerank with a conversational dense retriever in a cascaded manner achieves a good balance between effectiveness and efficiency. Compared to baseline methods, our cascaded pipeline demonstrates lower latency and higher top-ranking effectiveness. Furthermore, the in-depth analysis confirms the potential of our approach to improving the effectiveness of conversational search.Comment: SIGIR 202

Self-supervised learning-based general laboratory progress pretrained model for cardiovascular event detection

The inherent nature of patient data poses several challenges. Prevalent cases amass substantial longitudinal data owing to their patient volume and consistent follow-ups, however, longitudinal laboratory data are renowned for their irregularity, temporality, absenteeism, and sparsity; In contrast, recruitment for rare or specific cases is often constrained due to their limited patient size and episodic observations. This study employed self-supervised learning (SSL) to pretrain a generalized laboratory progress (GLP) model that captures the overall progression of six common laboratory markers in prevalent cardiovascular cases, with the intention of transferring this knowledge to aid in the detection of specific cardiovascular event. GLP implemented a two-stage training approach, leveraging the information embedded within interpolated data and amplify the performance of SSL. After GLP pretraining, it is transferred for TVR detection. The proposed two-stage training improved the performance of pure SSL, and the transferability of GLP exhibited distinctiveness. After GLP processing, the classification exhibited a notable enhancement, with averaged accuracy rising from 0.63 to 0.90. All evaluated metrics demonstrated substantial superiority (p < 0.01) compared to prior GLP processing. Our study effectively engages in translational engineering by transferring patient progression of cardiovascular laboratory parameters from one patient group to another, transcending the limitations of data availability. The transferability of disease progression optimized the strategies of examinations and treatments, and improves patient prognosis while using commonly available laboratory parameters. The potential for expanding this approach to encompass other diseases holds great promise.Comment: published in IEEE Journal of Translational Engineering in Health & Medicin

New Attenuation Relationship for Peak Ground and Pseudo-Spectral Acceleration of Normal-Faulting Earthquakes in Offshore Northeast Taiwan

Ground motions from normal-faulting earthquakes are generally considered to be smaller than those of strike-slip and thrust events. On 11 April 2011 a crustal normal-faulting earthquake [the Fukushima earthquake (Mw 6.6)] occurred in Eastern Japan. The peak ground acceleration (PGA) observed was considerably higher than the predictions of several ground-motion prediction equations (GMPEs), which were derived mainly from thrust or strike-slip earthquakes. In northeast Taiwan, the tectonic structure of the Ryukyu Arc and the Okinawa Trough typically entail normal-faulting earthquakes. Because of the normal-faulting earthquakes relevance to ground motions and nuclear power plant sites in northeast Taiwan, we evaluated the impact of the ground motion of normal-faulting earthquakes in offshore northeast Taiwan using a newly constructed attenuation relationship for PGA and pseudo-spectral acceleration (Sa). We collected 832 records from 13 normal-faulting earthquakes with focal depths of less than 50 km. The moment magnitude (Mw) of the 13 events was between 4 - 6. The Sa and PGA of normal-faulting earthquakes offshore northeast Taiwan determined with the newly constructed attenuation relationship were higher and lower, respectively, than those obtained using attenuation equations commonly used in the Taiwan subduction zone

Persistence Length Control of the Polyelectrolyte Layer-by-Layer Self-Assembly on Carbon Nanotubes

One-dimensional inorganic materials such as carbon nanotubes1 and semiconductor nanowires have been central to important advances in materials science in the last decade. Unique mechanical and electronic properties of these molecular-scale wires enabled a variety of applications ranging from novel composite materials, to electronic circuits, to new sensors. Often, these applications require non-covalent modification of carbon nanotubes with organic compounds, DNA and biomolecules, and polymers to change nanotube properties or to add new functionality. We recently demonstrated a versatile and flexible strategy for non-covalent modification of carbon nanotubes using layer-by-layer self-assembly of polyelectrolytes. Researchers used this technique extensively for modification of flat surfaces, micro-, and nano-particles; however, little is known about the mechanism and the factors influencing layer-by-layer self-assembly in one-dimensional nanostructures. The exact conformation of polyelectrolyte chains deposited on single-walled carbon nanotubes (SWNT) is still unknown. There are two possible configurations: flexible polymers wrapping around the nanotube and stretched, rigid chains stacked parallel to the nanotube axis. Several factors, such as polymer rigidity, surface curvature, and strength of polymer-surface interactions, can determine the nature of assembly. Persistence length of the polymer chain should be one of the critical parameters, since it determines the chain's ability to wrap around the nanotube. Indeed, computer simulations for spherical substrates show that polymer rigidity and substrate surface curvature can influence the deposition process. Computational models also show that the persistence length of the polymer must fall below the threshold values determined by target surface curvature in order to initiate polyelectrolyte deposition process. Although these models described the effects of salt concentration and target surface curvature, they considered only nano-particles with radius 5 nanometer and larger. One-dimensional materials, such as carbon nanotubes, provide an even more interesting template for studying self-assembly mechanisms, since they give us access to even smaller surface curvatures down to 1 nm. We have examined the role of the polymer persistence length in layer-by-layer self-assembly process on carbon nanotubes by observing formation of multilayer polyelectrolyte shells around carbon nanotubes at different ionic strength. Persistence length of polyelectrolytes varies with solution ionic strength, due to screening of the electrostatic repulsion between the polymer Figure 1. TEM images of single-walled carbon nanotubes after polymer deposition for ionic strengths of (A) 0.05M, (B) 0.1M, (C) 0.2M, (D) 0.4M, (E) 0.65M, and (F) 1.05M. Scale bar corresponds to 10 nm. backbone charges; therefore changing ionic strength is a convenient way to alter the configuration of the polymer molecule systematically. We have used the layer-by-layer self-assembly technique to form 5-layer thick coating of the alternating polyallylamine hydrochloride (PAH) and sodium poly(styrenesulfonate) (PSS) layers on the surfaces of the pristine single-wall carbon nanotubes. For our experiments, we grew the nanotubes across copper TEM grid openings using catalytic chemical vapor deposition. The deposition solutions contained different amounts of NaCl to vary the ionic strength. After polymer multilayer formation we examined the resulting coating in high-resolution TEM

Case report: Ruptured internal carotid artery fusiform aneurysm mimicking pituitary apoplexy after stereotactic radiosurgery

Pituitary adenomas are benign tumors of the anterior pituitary gland for which surgery or pharmacological treatment is the primary treatment. When initial treatment fails, radiation therapy should be considered. There are several case reports demonstrating radiation-induced vascular injury. We report an adult patient who presented with headache and diplopia for 6 months and a sellar tumor with optic chiasm compression. The patient received transnasal surgery, and the tumor was partially removed, which demonstrated adenoma. Stereotactic radiosurgery (SRS) was arranged. However, owing to progressive tumor growth, the patient received further transnasal surgery and stereotactic radiosurgery (SRS). After 14 years, the patient reported the sudden onset of headache and diplopia, and a ruptured fusiform aneurysm from the left internal carotid artery with pituitary apoplexy was diagnosed. The patient received transarterial embolization of the aneurysm. There were no complications after embolization, and this patient was ambulatory on discharge with blindness in the left eye and cranial nerve palsies. Aneurysm formation may be a complication of SRS, and it may occur after several years. Further research is needed to investigate the pathogenesis of radiosurgery and the development of cerebral aneurysms