Bayesian Hyperbolic Multidimensional Scaling

Multidimensional scaling (MDS) is a widely used approach to representing high-dimensional, dependent data. MDS works by assigning each observation a location on a low-dimensional geometric manifold, with distance on the manifold representing similarity. We propose a Bayesian approach to multidimensional scaling when the low-dimensional manifold is hyperbolic. Using hyperbolic space facilitates representing tree-like structures common in many settings (e.g. text or genetic data with hierarchical structure). A Bayesian approach provides regularization that minimizes the impact of measurement error in the observed data and assesses uncertainty. We also propose a case-control likelihood approximation that allows for efficient sampling from the posterior distribution in larger data settings, reducing computational complexity from approximately $O(n^2)$ to $O(n)$. We evaluate the proposed method against state-of-the-art alternatives using simulations, canonical reference datasets, Indian village network data, and human gene expression data

Alkaline Plasma-Activated Water (PAW) as an Innovative Therapeutic Avenue for Cancer Treatment

Plasma-activated water (PAW) is considered to be an effective anticancer agent due to the diverse aqueous reactive oxygen and nitrogen species (RONS: ROS and RNS), but the drawback of low dose and short duration of RONS in acidified PAW limits their clinical application. Herein, this Letter presents an innovative therapeutic avenue for cancer treatment with highly-effective alkaline PAW prepared by air surface plasma. This anticancer alkaline formulation is comprised of a rich mixture of highly chemical RONS and exhibited a prolonged half-life compared to acidified PAW. The H2O2, NO2-, and ONOO-/O2- concentrations in the alkaline PAW can reach up to 18-, 16-, and 14-fold higher than that in acidic PAW, and the half-life of these species was extended over 8-, 10-, and 26-fold, respectively. The synergistic potent redox action between these RONS with alkaline pH was shown to be more potent than acidic PAW for cancer cell inhibition in vitro. Furthermore, the alkaline PAW injection treatment also significantly inhibited tumor growth in tumor-bearing mice. The possible reasons are that the alkaline PAW would disturb the acid extracellular milieu leading to the inhibition of tumor growth and progression; moreover, the efficient and durable RONS with alkaline pH could induce significant cell apoptosis by altering cell biomolecules and participating apoptosis-related signaling pathways. These findings offer promising applications for developing a strategy with real potential for tumor treatment in clinical applications

Utilization and Short-term Outcomes of Percutaneous Left Atrial Appendage Occlusion in Patients With Cancer

Background Percutaneous left atrial appendage occlusion (LAAO) has been rapidly evolving since FDA’s approval in 2015 and has become more of a same-day-discharge procedure. Cancer patient with atrial fibrillation/flutter (AF) population can benefit from the procedure but the in-hospital outcomes and readmission data were rarely studied. Objectives We investigated the utilization, in-hospital and readmission outcomes in cancer patients with AF who underwent LAAO. Methods Data were derived from the National Inpatient Sample and National Readmissions Database from 2016 to 2019. Patients with primary diagnosis of AF admitted for LAAO (ICD-10 code 02L73DK) were grouped by cancer as a secondary diagnosis. We assessed in-hospital mortality, length of stay, total hospital charges, and complications. Thirty-day readmission rates were compared. Results LAAO was performed in 60,380 patients with AF and 3% were cancer patients. There were no differences in in-hospital mortality and total hospital charges; however, cancer patients tended to have longer hospital stay (1.59 ± 0.11 vs. 1.32 ± 0.02, p = 0.013). Among complications, cancer patients had higher rates in open or percutaneous pericardial drainage (adjusted odds ratio [aOR] 2.38; 95% confidence interval [CI] 1.19–4.76) and major bleeding events (aOR 7.07; 95% CI 1.82–27.38). There was no statistical significance of 30-day readmission rates between patients with and without cancer (10.0% vs. 9.1%, p = 0.34). The most common readmission reason in cancer patients was gastrointestinal bleeding. Conclusions LAAO is a promising procedure in cancer patients complicated by AF with contraindication to anticoagulation. Readmission rate is comparable between patients with and without cancer

A new opportunity for the emerging tellurium semiconductor: making resistive switching devices

Abstract: The development of the resistive switching cross-point array as the next-generation platform for high-density storage, in-memory computing and neuromorphic computing heavily relies on the improvement of the two component devices, volatile selector and nonvolatile memory, which have distinct operating current requirements. The perennial current-volatility dilemma that has been widely faced in various device implementations remains a major bottleneck. Here, we show that the device based on electrochemically active, low-thermal conductivity and low-melting temperature semiconducting tellurium filament can solve this dilemma, being able to function as either selector or memory in respective desired current ranges. Furthermore, we demonstrate one-selector-one-resistor behavior in a tandem of two identical Te-based devices, indicating the potential of Te-based device as a universal array building block. These nonconventional phenomena can be understood from a combination of unique electrical-thermal properties in Te. Preliminary device optimization efforts also indicate large and unique design space for Te-based resistive switching devices

Non-Hermitian topological whispering gallery

In 1878, Lord Rayleigh observed the highly celebrated phenomenon of sound waves that creep around the curved gallery of St Paul's Cathedral in London1,2. These whispering-gallery waves scatter efficiently with little diffraction around an enclosure and have since found applications in ultrasonic fatigue and crack testing, and in the optical sensing of nanoparticles or molecules using silica microscale toroids. Recently, intense research efforts have focused on exploring non-Hermitian systems with cleverly matched gain and loss, facilitating unidirectional invisibility and exotic characteristics of exceptional points3,4. Likewise, the surge in physics using topological insulators comprising non-trivial symmetry-protected phases has laid the groundwork in reshaping highly unconventional avenues for robust and reflection-free guiding and steering of both sound and light5,6. Here we construct a topological gallery insulator using sonic crystals made of thermoplastic rods that are decorated with carbon nanotube films, which act as a sonic gain medium by virtue of electro-thermoacoustic coupling. By engineering specific non-Hermiticity textures to the activated rods, we are able to break the chiral symmetry of the whispering-gallery modes, which enables the out-coupling of topological "audio lasing" modes with the desired handedness. We foresee that these findings will stimulate progress in non-destructive testing and acoustic sensing.This work was supported by the National Basic Research Program of China (2017YFA0303702), NSFC (12074183, 11922407, 11904035, 11834008, 11874215 and 12104226) and the Fundamental Research Funds for the Central Universities (020414380181). Z.Z. acknowledges the support from the China National Postdoctoral Program for Innovative Talents (BX20200165) and the China Postdoctoral Science Foundation (2020M681541). L.Z. acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement 801538. J.C. acknowledges support from the European Research Council (ERC) through the Starting Grant 714577 PHONOMETA and from the MINECO through a Ramón y Cajal grant (grant number RYC-2015-17156)

Februus: Input Purification Defense Against Trojan Attacks on Deep Neural Network Systems

We propose Februus; a new idea to neutralize highly potent and insidious Trojan attacks on Deep Neural Network (DNN) systems at run-time. In Trojan attacks, an adversary activates a backdoor crafted in a deep neural network model using a secret trigger, a Trojan, applied to any input to alter the model's decision to a target prediction---a target determined by and only known to the attacker. Februus sanitizes the incoming input by surgically removing the potential trigger artifacts and restoring the input for the classification task. Februus enables effective Trojan mitigation by sanitizing inputs with no loss of performance for sanitized inputs, Trojaned or benign. Our extensive evaluations on multiple infected models based on four popular datasets across three contrasting vision applications and trigger types demonstrate the high efficacy of Februus. We dramatically reduced attack success rates from 100% to near 0% for all cases (achieving 0% on multiple cases) and evaluated the generalizability of Februus to defend against complex adaptive attacks; notably, we realized the first defense against the advanced partial Trojan attack. To the best of our knowledge, Februus is the first backdoor defense method for operation at run-time capable of sanitizing Trojaned inputs without requiring anomaly detection methods, model retraining or costly labeled data.Comment: 16 pages, to appear in the 36th Annual Computer Security Applications Conference (ACSAC 2020