643 results match your criteria parameter update

Automatic, dynamic, and nearly optimal learning rate specification via local quadratic approximation.

Neural Netw 2021 Mar 26;141:11-29. Epub 2021 Mar 26.

Guanghua School of Management, Peking University, Beijing, China. Electronic address:

In deep learning tasks, the update step size determined by the learning rate at each iteration plays a critical role in gradient-based optimization. However, determining the appropriate learning rate in practice typically relies on subjective judgment. In this work, we propose a novel optimization method based on local quadratic approximation (LQA). Read More

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Treatment Strategy in Human Ocular Toxoplasmosis: Why Antibiotics Have Failed.

J Clin Med 2021 Mar 5;10(5). Epub 2021 Mar 5.

Department of Ophthalmology, Campus Virchow, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Charité, 13353 Berlin, Germany.

Background: There is currently no clear evidence of the effectiveness of antibiotic therapy in acute ocular toxoplasmosis (OT), but its effect as a secondary prophylaxis is undisputed. The majority of uveitis specialists advocate treatment. This meta-analytic review aims to critically analyze determinants of treatment success and to update current treatment strategies for OT in order to explain this discrepancy. Read More

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Kernel Probabilistic K-Means Clustering.

Sensors (Basel) 2021 Mar 8;21(5). Epub 2021 Mar 8.

Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China.

Kernel fuzzy c-means (KFCM) is a significantly improved version of fuzzy c-means (FCM) for processing linearly inseparable datasets. However, for fuzzification parameter m=1, the problem of KFCM (kernel fuzzy c-means) cannot be solved by Lagrangian optimization. To solve this problem, an equivalent model, called kernel probabilistic k-means (KPKM), is proposed here. Read More

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A Sparse Volume Reconstruction Method for Fetal Brain MRI Using Adaptive Kernel Regression.

Biomed Res Int 2021 5;2021:6685943. Epub 2021 Mar 5.

Suzhou Institute of Advanced Technology, Chinese Academy of Sciences, Suzhou, China.

Slice-to-volume reconstruction (SVR) method can deal well with motion artifacts and provide high-quality 3D image data for fetal brain MRI. However, the problem of sparse sampling is not well addressed in the SVR method. In this paper, we mainly focus on the sparse volume reconstruction of fetal brain MRI from multiple stacks corrupted with motion artifacts. Read More

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Mi3-GPU: MCMC-based Inverse Ising Inference on GPUs for protein covariation analysis.

Comput Phys Commun 2021 Mar 17;260. Epub 2020 Apr 17.

Center for Biophysics and Computational Biology and Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122.

Inverse Ising inference is a method for inferring the coupling parameters of a Potts/Ising model based on observed site-covariation, which has found important applications in protein physics for detecting interactions between residues in protein families. We introduce Mi3-GPU ("mee-three", for CMC nverse sing nference) software for solving the inverse Ising problem for protein-sequence datasets with few analytic approximations, by parallel Markov-Chain Monte-Carlo sampling on GPUs. We also provide tools for analysis and preparation of protein-family Multiple Sequence Alignments (MSAs) to account for finite-sampling issues, which are a major source of error or bias in inverse Ising inference. Read More

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Unsupervised Classification of Polarimetric SAR Image Based on Geodesic Distance and Non-Gaussian Distribution Feature.

Sensors (Basel) 2021 Feb 12;21(4). Epub 2021 Feb 12.

Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China.

Polarimetric synthetic aperture radar (PolSAR) image classification plays a significant role in PolSAR image interpretation. This letter presents a novel unsupervised classification method for PolSAR images based on the geodesic distance and K-Wishart distribution. The geodesic distance is obtained between the Kennaugh matrices of the observed target and canonical targets, and it is further utilized to define scattering similarity. Read More

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February 2021

Recent update of toxicity aspects of nanoparticulate systems for drug delivery.

Eur J Pharm Biopharm 2021 Apr 25;161:100-119. Epub 2021 Feb 25.

Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi 110062, India. Electronic address:

Potential research outcomes on nanotechnology-based novel drug delivery systems since the past few decades attracted the attention of the researchers to overcome the limitations of conventional deliveries. Apart from possessing enhanced solubility of poorly water-soluble drugs, the targeting potential of the carriers facilitates longer circulation and site-specific delivery of the entrapped therapeutics. The practice of these delivery systems, therefore, helps in maximizing bioavailability, improving pharmacokinetics profile, pharmacodynamics activity and biodistribution of the entrapped drug(s). Read More

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Variational HyperAdam: A Meta-learning Approach to Network Training.

IEEE Trans Pattern Anal Mach Intell 2021 Feb 23;PP. Epub 2021 Feb 23.

Human-designed stochastic optimization algorithms are popular tools for deep neural network training. Recently, there emerges a new approach of learning to optimize network parameter, which has achieved promising results. However, these black-box optimizers based on learning do not fully take advantage of the experiences in human-designed optimizers, therefore have limited generalization ability. Read More

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February 2021

Diagnostic algorithm in septic total knee arthroplasty failure - What is evidence-based?

J Orthop 2021 Jan-Feb;23:208-215. Epub 2021 Jan 28.

Department of Orthopedics and Sports Orthopedics, Klinikum Rechts der Isar, Technical University of Munich (TUM), Ismaningerstr. 22, 81675, Munich, Germany.

Prosthetic joint infection (PJI) is among the most common differential diagnoses of total knee arthroplasty failure. It is a challenging complication, not least because of the difficulty of establishing the correct diagnosis. The fact that no single diagnostic parameter or test has been identified that can accurately rule in or out PJI has led to an evolution of similar but competing definitions of PJI on the grounds of an array of criteria. Read More

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January 2021

Visual scanning strategies in the cockpit are modulated by pilots' expertise: A flight simulator study.

PLoS One 2021 18;16(2):e0247061. Epub 2021 Feb 18.

ISAE-SUPAERO, Université de Toulouse, Toulouse, France.

During a flight, pilots must rigorously monitor their flight instruments since it is one of the critical activities that contribute to update their situation awareness. The monitoring is cognitively demanding, but is necessary for timely intervention in the event of a parameter deviation. Many studies have shown that a large part of commercial aviation accidents involved poor cockpit monitoring from the crew. Read More

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February 2021

An α -β -Divergence-Generalized Recommender for Highly Accurate Predictions of Missing User Preferences.

IEEE Trans Cybern 2021 Feb 18;PP. Epub 2021 Feb 18.

To quantify user-item preferences, a recommender system (RS) commonly adopts a high-dimensional and sparse (HiDS) matrix. Such a matrix can be represented by a non-negative latent factor analysis model relying on a single latent factor (LF)-dependent, non-negative, and multiplicative update algorithm. However, existing models' representative abilities are limited due to their specialized learning objective. Read More

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February 2021

Safety and efficacy of hydrothermal duodenal mucosal resurfacing in patients with type 2 diabetes: the randomised, double-blind, sham-controlled, multicentre REVITA-2 feasibility trial.

Gut 2021 Feb 17. Epub 2021 Feb 17.

Departments of Gastroenterology and Hepatology, Academic Medical Center Amsterdam, Amsterdam, The Netherlands.

Objective: Hydrothermal duodenal mucosal resurfacing (DMR) is a safe, outpatient endoscopic procedure. REVITA-2, a double-blind, superiority randomised controlled trial, investigates safety and efficacy of DMR using the single catheter Revita system (Revita DMR (catheter and system)), on glycaemic control and liver fat content in type 2 diabetes (T2D).

Design: Eligible patients (haemoglobin A1c (HbA1c) 59-86 mmol/mol, body mass index≥24 and ≤40 kg/m, fasting insulin >48. Read More

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February 2021

Few-shot pulse wave contour classification based on multi-scale feature extraction.

Sci Rep 2021 Feb 12;11(1):3762. Epub 2021 Feb 12.

The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450001, China.

The annotation procedure of pulse wave contour (PWC) is expensive and time-consuming, thereby hindering the formation of large-scale datasets to match the requirements of deep learning. To obtain better results under the condition of few-shot PWC, a small-parameter unit structure and a multi-scale feature-extraction model are proposed. In the small-parameter unit structure, information of adjacent cells is transmitted through state variables. Read More

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February 2021

High-Performance Organic Synaptic Transistors with an Ultrathin Active Layer for Neuromorphic Computing.

ACS Appl Mater Interfaces 2021 Feb 10;13(7):8672-8681. Epub 2021 Feb 10.

Institute of Optoelectronic Display, National & Local United Engineering Lab of Flat Panel Display Technology, Fuzhou University, Fuzhou 350002, China.

In recent years, much attention has been focused on two-dimensional (2D) material-based synaptic transistor devices because of their inherent advantages of low dimension, simultaneous read-write operation and high efficiency. However, process compatibility and repeatability of these materials are still a big challenge, as well as other issues such as complex transfer process and material selectivity. In this work, synaptic transistors with an ultrathin organic semiconductor layer (down to 7 nm) were obtained by the simple dip-coating process, which exhibited a high current switch ratio up to 10, well off state as low as nearly 10 A, and low operation voltage of -3 V. Read More

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February 2021

Event-Triggered Control of Nonlinear Discrete-Time System With Unknown Dynamics Based on HDP(λ).

IEEE Trans Cybern 2021 Feb 2;PP. Epub 2021 Feb 2.

The heuristic dynamic programming (HDP) (λ)-based optimal control strategy, which takes a long-term prediction parameter λ into account using an iterative manner, accelerates the learning rate obviously. The computation complexity caused by the state-associated extra variable in λ-return value computing of the traditional value-gradient learning method can be reduced. However, as the iteration number increases, calculation costs have grown dramatically that bring huge challenge for the optimal control process with limited bandwidth and computational units. Read More

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February 2021

Clinical Guideline Highlights for the Hospitalist: Anaphylaxis Management in Adults and Children.

J Hosp Med 2021 Feb;16(2):98-99

Department of Internal Medicine, University of Tennessee Health Sciences Center, Memphis, Tennessee.

Guideline Title: Anaphylaxis-A 2020 practice parameter update, systematic review, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis RELEASE DATE: April 2020 PRIOR VERSION: Anaphylaxis - a 2019 practice parameter and GRADE analysis DEVELOPER: American Academy of Allergy, Asthma & Immunology (AAAAI) and the American College of Allergy, Asthma, and Immunology (ACAAI) FUNDING SOURCE: None TARGET POPULATION: Adult and pediatric patients with anaphylaxis. Read More

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February 2021

Estimation of stride-by-stride spatial gait parameters using inertial measurement unit attached to the shank with inverted pendulum model.

Sci Rep 2021 Jan 14;11(1):1391. Epub 2021 Jan 14.

Department of Computer Science, Tokyo Institute of Technology, Kanagawa, 226-8503, Japan.

Inertial measurement unit (IMU)-based gait analysis systems have become popular in clinical environments because of their low cost and quantitative measurement capability. When a shank is selected as the IMU mounting position, an inverted pendulum model (IPM) can accurately estimate its spatial gait parameters. However, the stride-by-stride estimation of gait parameters using one IMU on each shank and the IPMs has not been validated. Read More

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January 2021

The Clinical Laboratory: A Key Player in Diagnosis and Management of COVID-19.

EJIFCC 2020 Nov 20;31(4):326-346. Epub 2020 Nov 20.

Department of Biochemistry, All India institute of Medical Sciences, Jodhpur, Rajasthan, India.

The Coronavirus disease 2019 (COVID-19) outbreak, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), had emerged as a pandemic affecting almost all countries in the world in a short span after it was first reported in December. Clinical laboratory have a crucial role in mitigating this new pandemic. Timely and accurate diagnosis of COVID-19 is of paramount importance for detecting cases early and to prevent transmission. Read More

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November 2020

A technique based on nonlinear Hanning-windowed chirplet model and genetic algorithm for parameter estimation of Lamb wave signals.

Ultrasonics 2021 Mar 16;111:106333. Epub 2020 Dec 16.

Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, China; Beijing Engineering Research Center of Precision Measurement Technology and Instruments, Beijing University of Technology, Beijing 100124, China.

Parameter estimation techniques based on chirplet models and intelligent algorithms can realize the simultaneous multi-information extraction of signals. They have attracted considerable attention for the processing of Lamb wave signals to detect defects and evaluate the material properties. Influenced by their dispersive nature, Lamb wave signals possess nonlinear instantaneous frequencies and asymmetric envelopes. Read More

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Update on Thrombocytopenia in Pregnancy.

Rev Bras Ginecol Obstet 2020 Dec 21;42(12):834-840. Epub 2020 Dec 21.

Universidade de Coimbra, Coimbra, Portugal.

Thrombocytopenia, defined as platelet count < 150,000 mm, is frequently diagnosed by obstetricians since this parameter is included in routine surveillance during pregnancy, with an incidence of between 7 and 12%. Therefore, decisions regarding subsequent examination and management are primordial. While most of the cases are due to physiological changes, as gestational thrombocytopenia, other causes can be related to severe conditions that can lead to fetal or maternal death. Read More

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December 2020

Epidemiology of a SKin Ulceration Disease (SKUD) in the sea cucumber Holothuria scabra with a review on the SKUDs in Holothuroidea (Echinodermata).

Sci Rep 2020 12 17;10(1):22150. Epub 2020 Dec 17.

Biology of Marine Organisms and Biomimetics, Research Institute for Biosciences, University of Mons - UMONS, Place du Parc, 6, 7000, Mons, Belgium.

Aquacultivated sea cucumbers often suffer from SKin Ulceration Diseases (SKUDs). SKUDs have been observed in six holothuroid species from nine countries. All SKUDs present a similar symptom-the skin ulceration-and can be induced by bacteria, viruses, or abiotic factors. Read More

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December 2020

Mesh Denoising with Facet Graph Convolutions.

IEEE Trans Vis Comput Graph 2020 Dec 17;PP. Epub 2020 Dec 17.

We examine the problem of mesh denoising, which consists of removing noise from corrupted 3D meshes while preserving existing geometric features. Most mesh denoising methods require a lot of mesh-specific parameter fine-tuning, to account for specific features and noise types. In recent years, data-driven methods have demonstrated their robustness and effectiveness with respect to noise and feature properties on a wide variety of geometry and image problems. Read More

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December 2020

Finite-Time Command-Filtered Composite Adaptive Neural Control of Uncertain Nonlinear Systems.

IEEE Trans Cybern 2020 Dec 10;PP. Epub 2020 Dec 10.

This article presents a new command-filtered composite adaptive neural control scheme for uncertain nonlinear systems. Compared with existing works, this approach focuses on achieving finite-time convergent composite adaptive control for the higher-order nonlinear system with unknown nonlinearities, parameter uncertainties, and external disturbances. First, radial basis function neural networks (NNs) are utilized to approximate the unknown functions of the considered uncertain nonlinear system. Read More

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December 2020

A-DVM: A Self-Adaptive Variable Matrix Decision Variable Selection Scheme for Multimodal Problems.

Entropy (Basel) 2020 Sep 9;22(9). Epub 2020 Sep 9.

School of Systems and Information Engineering, University of Tsukuba, Tsukuba 305-8577, Japan.

Artificial Bee Colony (ABC) is a Swarm Intelligence optimization algorithm well known for its versatility. The selection of decision variables to update is purely stochastic, incurring several issues to the local search capability of the ABC. To address these issues, a self-adaptive decision variable selection mechanism is proposed with the goal of balancing the degree of exploration and exploitation throughout the execution of the algorithm. Read More

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September 2020

Numerical Convergence Analysis of the Frank-Kamenetskii Equation.

Entropy (Basel) 2020 Jan 9;22(1). Epub 2020 Jan 9.

Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Århus C, Denmark.

This work investigates the convergence dynamics of a numerical scheme employed for the approximation and solution of the Frank-Kamenetskii partial differential equation. A framework for computing the critical Frank-Kamenetskii parameter to arbitrary accuracy is presented and used in the subsequent numerical simulations. The numerical method employed is a Crank-Nicolson type implicit scheme coupled with a fourth order spatial discretisation as well as a Newton-Raphson update step which allows for the nonlinear source term to be treated implicitly. Read More

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January 2020

Atmospheric wind and temperature profiles inversion using infrasound: An ensemble model context.

J Acoust Soc Am 2020 Nov;148(5):2923

CEA, DAM, DIF, F-91297 Arpajon, France.

This paper presents an inversion methodology where acoustic observations of infrasound waves are used to update an atmospheric model. This paper sought a flexible parameterization that permits to incorporate physical and numerical constraints without the need to reformulate the inversion. On the other hand, the optimization conveys an explicit search over the solution space, making the solver computationally expensive. Read More

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November 2020

Matched-field geoacoustic inversion based on radial basis function neural network.

J Acoust Soc Am 2020 11;148(5):3279

Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, USA.

Multi-layer neural networks (NNs) are combined with objective functions of matched-field inversion (MFI) to estimate geoacoustic parameters. By adding hidden layers, a radial basis function neural network (RBFNN) is extended to adopt MFI objective functions. Specifically, shallow layers extract frequency features from the hydrophone data, and deep layers perform inverse function approximation and parameter estimation. Read More

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November 2020

Effect of chaotic agent dynamics on coevolution of cooperation and synchronization.

Chaos 2020 Nov;30(11):113111

Department of Physics, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India.

The effect of chaotic dynamical states of agents on the coevolution of cooperation and synchronization in a structured population of the agents remains unexplored. With a view to gaining insights into this problem, we construct a coupled map lattice of the paradigmatic chaotic logistic map by adopting the Watts-Strogatz network algorithm. The map models the agent's chaotic state dynamics. Read More

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November 2020

Congress of neurological surgeons systematic review and evidence-based clinical practice parameter guidelines for the treatment of adults with newly diagnosed glioblastoma: Introduction and Methods.

J Neurooncol 2020 Nov 19;150(2):87-93. Epub 2020 Nov 19.

Section of Neurosurgery, Dartmouth University, Hanover, NH, USA.

Purpose: This is an update of the evidence-based guideline for management of newly diagnosed glioblastomas sponsored by the American Association of Neurological Surgeons (AANS) and Congress of Neurological Surgeons (CNS) initially published in 2008. The objective is to update evidence-based management of newly diagnosed glioblastomas over all commonly used diagnostic and treatment modalities in regularly encountered clinical situations.

Methods: A multidisciplinary writing group was assembled to create documents related to imaging, cytoreductive surgery, neuropathology, radiation therapy, chemotherapy and emerging developments. Read More

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November 2020

Long-term adherence to home mechanical ventilation: a 10-year retrospective, single-centre cohort study.

J Thorac Dis 2020 Oct;12(Suppl 2):S120-S128

Faculty of Life Sciences and Medicine, King's College London, London, UK.

Background: Sleep-disordered breathing (SBD) can be associated with hypercapnic respiratory failure (HRF). Home Mechanical Ventilation (HMV) is the preferred long-term treatment for patients with chronic HRF. We reviewed the database of a large tertiary referral centre for HMV to study the long-term adherence to HMV in chronic hypercapnic patients. Read More

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October 2020