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Random Walks with Variable Restarts for Negative-Example-Informed Label Propagation
Get PDFLabel propagation is frequently encountered in machine learning and data mining applications on graphs, either as a standalone problem or as part of node classification. Many label propagation algorithms utilize random walks (or network propagation), which provide limited ability to take into account negatively-labeled nodes (i.e., nodes that are known to be not associated with the label of interest). Specialized algorithms to incorporate negatively-labeled nodes generally focus on learning or readjusting the edge weights to drive walks away from negatively-labeled nodes and toward positively-labeled nodes. This approach has several disadvantages, as it increases the number of parameters to be learned, and does not necessarily drive the walk away from regions of the network that are rich in negatively-labeled nodes. We reformulate random walk with restarts and network propagation to enable “variable restarts , that is the increased likelihood of restarting at a positively-labeled node when a negatively-labeled node is encountered. Based on this reformulation, we develop CusTaRd, an algorithm that effectively combines variable restart probabilities and edge re-weighting to avoid negatively-labeled nodes. To assess the performance of CusTaRd, we perform comprehensive experiments on network datasets commonly used in benchmarking label propagation and node classification algorithms. Our results show that CusTaRd consistently outperforms competing algorithms that learn edge weights or restart profiles, and that negatives close to positive examples are generally more informative than more distant negatives
COVID-19 Infection Increases the Development of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Retrospective Cohort Analysis
Get PDFTo the Editor: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) represent a spectrum of severe mucocutaneous reactions characterized by extensive epidermal detachment, most commonly due to medications.1 Some viruses, such as the human immunodeficiency virus, have been found to be an independent risk factor for the development of SJS and TEN, though the mechanism is not completely understood.2 Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus identified in late 2019, is most commonly associated with mild respiratory illness. However, cutaneous manifestations, including SJS and TEN, have been increasingly reported during and after COVID-19 infection.3 Therefore, the objective of this study is to determine the impact of COVID-19 infection on the incidence of SJS/TEN and to characterize mortality in patients with both SJS/TEN and COVID-19
Administration Patterns of Magnesium Sulphate for Women with Preeclampsia and Immediate Newborn Outcomes in Kawempe National Referral Hospital-Uganda: A Cohort Study
No full textBackground: Preeclampsia is the second leading cause of maternal death in Uganda. WHO recommends using magnesium sulphate (MgSO4) to prevent and treat preeclampsia with severe features (PEC) and eclampsia. MgSO4 is used to prevent eclampsia and treat women who experience an eclamptic convulsion to avoid severe maternal/infant illnesses and death. We set out to assess MgSO4 administration patterns in women with PEC or eclampsia and the immediate newborn outcomes of neonates. Methods: This was an analytical observational cohort study at Kawempe National Referral Hospital in Uganda. Two hundred ten pregnant mothers with PEC or eclampsia were recruited in the study after receiving the loading dose of MgSO4 and then followed through labour and delivery to observe MgSO4 administration patterns and immediate newborn outcomes using Apgar and Thompson scores. SPSS version 23 was used to analyse data, and both bivariate and multivariate logistic regressions were used to determine factors associated with the low Apgar score at five minutes. Results: Overall, majority of the patients received more than one dose with 33.3% received a sixth dose of MgSO4. The majority, 84.8%, of the mothers delivered live babies, 31.0% babies had complications, and were admitted to the neonatal intensive care unit (NICU). NICU admissions were mostly due to respiratory distress21.4%, preterm delivery21.0%, and 5.5% died within seven days. Majority 93.3% of the newborns had an Apgar score of seven and above at five minutes, of the newborns who were Thompson scored, 70.4% scored between 1 to 10 which is mild HIE. Initiation of MgSO4 treatment within one hour from prescription (AOR = 0.49, CI: 0.01–1.94), 4-hourly timing of the first maintenance dose (AOR = 0.22, CI: 0.06–0.79) and having complete doses of MgSO4 treatment (AOR = 0.89, CI: 0.03–3.05) decreased the likelihood of having low Apgar scores at five minutes. Conclusions: Timely administration of the first maintenance dose of MgSO4 decreases the likelihood of low Apgar score at 5 min and NICU admission in newborns, and most NICU admissions were due to respiratory distress and preterm delivery
Composition-property Relationships of Choline Based Eutectic Solvents: Impact of the Hydrogen Bond Donor and CO2 Saturation
No full textEutectic solvents are tunable for targeted applications through the functional groups in their hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD) components, as well as the HBA : HBD composition ratio. This study examines the properties of choline-based eutectics containing imidazole, phenol, pyrrole-2-carbonitrile, and 1,2,4-triazole HBAs, and ethylene glycol, 1,2-propylene glycol, and ethanolamine HBDs. The viscosity, conductivity, degree of hydrogen bonding, thermal stability, and solvatochromic properties are examined as a function of HBA, HBD, and the composition. These studies revealed a predominant dependence of physical properties on the HBD and determined that the strong hydrogen bonding in phenol and imidazole-based systems lead to higher viscosities and lower conductivities - critical parameters for CO2 capture and electrochemical conversion. The developed eutectic solvents were further evaluated in terms of their CO2 capture capacities and electrochemical stabilities. Solvatochromic properties were found to correlate with CO2 capacities, demonstrating the tunability of these solvents for CO2 capture. The quantitative structure-property relationship (QSPR) analysis demonstrated the ability to predict viscosities and CO2 capture capacities (\u3c 25% deviation) through a multi linear regression method utilizing five molecular descriptors. This work highlights the role of functionalized HBAs and HBDs in the physical, thermal, and electrochemical properties of eutectic solvents as they relate to CO2 capture and electrochemical processes
Integrating Multiscale Geospatial Analysis for Monitoring Crop Growth, Nutrient Distribution, and Hydrological Dynamics in Large-Scale Agricultural Systems
No full textMonitoring crop growth, soil conditions, and hydrological dynamics are imperative for sustainable agriculture and reduced environmental impacts. This interdisciplinary study integrates remote sensing, digital soil mapping, and hydrological data to elucidate intricate connections between these factors in the state of Ohio, USA. Advanced spatiotemporal analysis techniques were applied to key datasets, including the MODIS sensor satellite imagery, USDA crop data, soil datasets, Aster GDEM, and USGS stream gauge measurements. Vegetation indices derived from MODIS characterized crop-specific phenology and productivity patterns. Exploratory spatial data analysis show relationships of vegetation dynamics and soil properties, uncovering links between plant vigor, edaphic fertility, and nutrient distributions. Correlation analysis quantified these relationships and their seasonal evolution. Examination of stream gauge data revealed insights into spatiotemporal relationships of nutrient pollution and stream discharge. By synthesizing diverse geospatial data through cutting-edge data analytics, this work illuminated complex interactions between crop health, soil nutrients, and water quality in Ohio. The methodology and findings provide actionable perspectives to inform sustainable agricultural management and environmental policy. This study demonstrates the significant potential of open geospatial resources when integrated using a robust spatiotemporal framework. Integrating additional measurements and high-resolution data sources through advanced analytics and interactive visualizations could strengthen these insights
Electrochemical Biosensing of Cerium With a Tyrosine-Functionalized EF-Hand Loop Peptide
No full textThe significance of easily detecting rare earth elements (REEs) has increased due to the growing demand for REEs. Addressing this need, we present an innovative electrochemical biosensor, focusing on cerium as a model REE. This biosensor utilizes a modified EF-hand loop peptide sequence, incorporating cysteine for covalent attachment to a gold working electrode and tyrosine as an electrochemically active amino acid. The sensor was designed such that binding to cerium induces a conformational change in the peptide, affecting tyrosine\u27s proximity to the electrode surface, modulating the current. A calibration curve was generated from cyclic voltammetry current peaks at ~0.55–0.65 V versus a silver pseudo-reference electrode, with cerium concentrations ranging from 0 to 67 μM in artificial urine. The sensor exhibited a biologically relevant limit of detection of 35 μM and a sensitivity of −0.0024 ± 0.002 (μA μM)−1. These findings offer insights into designing peptide sequences for electrochemical biosensing
Nonlinear Ferroelectric Characteristics of Barium Titanate Nanocrystals Determined via a Polymer Nanocomposite Approach
No full textThe growing demand for high energy storage materials has garnered substantial attention towards lead-free ferroelectric nanocrystals (NCs), such as BaTiO3 (BTO), for next-generation multilayer ceramic capacitors. Notably, it remains challenging to accurately measure the dielectric constant and polarization-electric field (P-E) hysteresis loop for BTO NCs. Herein, we report on nonlinear ferroelectric characteristics of BTO NCs via a polymer nanocomposite approach. Specifically, poly(vinyl pyrrolidone) (PVP)/BTO nanocomposite films of 3-10 μm thickness, containing 380 nm tetragonal-phased and 60 nm cubic-phased BTO NCs with uniform particle dispersion, were prepared. Theoretical deconvolution of the broad experimental P-E loops of the PVP/BTO NC composite films revealed three contributions, that is, the linear deformational polarization of the nanocomposites, the polarization of BTO NCs (Pp), and the polarization from strong particle-particle interactions. Using different mixing rules and nonlinear dielectric analysis, the overall dielectric constants of BTO NCs were obtained, from which the internal field in the BTO NCs (Ep) was estimated. Consequently, the Pp-Ep hysteresis loops were obtained for the BTO380 and BTO60 NCs. Interestingly, BTO380 exhibited square-shaped ferroelectric loops, whereas BTO60 displayed slim paraelectric loops. This work presents a robust and versatile route to extract the Pp-Ep loops of ferroelectric NCs from polymer/ceramic nanocomposites
Effects of Confinement on Opposed-Flow Flame Spread Over Cellulose and Polymeric Solids in Microgravity
No full textOpposed-flow flame spread over solid materials has been investigated in the past few decades owing to its importance in fundamental understanding of fires. These studies provided insights on the behavior of opposed-flow flames in different environmental conditions (e.g., flow speed, oxygen concentration). However, the effect of confinement on opposed-flow flames remains under-explored. It is known that confinement plays a critical role in concurrent-flow flame spread in normal and microgravity conditions. Hence, for a complete understanding it becomes important to understand the effects of confinement for opposed-flow flames. In this study, microgravity experiments are conducted aboard the International Space Station (ISS) to investigate opposed-flow flame spread in different confined conditions. Two materials, cotton-fiberglass blended textile fabric (SIBAL) and 1 mm thick polymethyl methacrylate (PMMA) slab are burned between a pair of parallel flow baffles in a small flow duct. By varying the sample-baffle distance, various levels of confinement are achieved (H = 1–2 cm). Three types of baffles, transparent, black, and reflective, are used to create different radiative boundary conditions. The purely forced flow speed is also varied (between 2.6 and 10.5 cm/s) to investigate its interplay with the confinement level. For both sample materials, it is observed that the flame spread rate decreases when the confinement level increases (i.e., when H decreases). In addition, flame spread rate is shown to have a positive correlation with flow speed, up to an optimal value. The results also indicate that the optimal flow speed for flame spread can decrease in highly confined conditions. Surface radiation on the confinement boundary is shown to play a key role. For SIBAL fabric, stronger flames are observed when using black baffles compared to transparent. For PMMA, reflective baffles yield stronger flames compared to black baffles. When comparing the results to the concurrent-flow case, it is also noticed that opposed-flow flames spread slower and blow off at larger flow speeds but are not as sensitive to the flow speed. This work provides unique long-duration microgravity experimental data that can inform the design of future opposed-flow experiments in microgravity and the development of theory and numerical models
Proceedings of the 2022 “Lifestyle Intervention for Epilepsy (LIFE)” Symposium Hosted by Cleveland Clinic
No full textLifestyle interventions are strategies used to self-manage medical conditions, such as epilepsy, and often complement traditional pharmacologic and surgical therapies. The need for integrating evidence-based lifestyle interventions into mainstream medicine for the treatment of epilepsy is evident given that despite the availability of a multitude of treatments with medications and surgical techniques, a significant proportion of patients have refractory seizures, and even those who are seizure-free report significant adverse effects with current treatments. Although the evidence base for complementary medicine is less robust than it is for traditional forms of medicine, the evidence to date suggests that several forms of complementary medicine including yoga, mindfulness meditation, cognitive behavioral therapy, diet and nutrition, exercise and memory rehabilitation, and music therapy may have important roles as adjuncts in the treatment armamentarium for epilepsy. These topics were discussed by a diverse group of medical providers and scientists at the “Lifestyle Intervention for Epilepsy (LIFE)” symposium hosted by Cleveland Clinic. Plain Language Summary: There are many people with epilepsy who continue to have seizures even though they are being treated with medication or brain surgery. Even after seizures stop, some may experience medication side effects. There is research to suggest that certain lifestyle changes, such as yoga, mindfulness, exercise, music therapy, and adjustments to diet, could help people with epilepsy, when used along with routine treatment. Experts discussed the latest research at the “Lifestyle Intervention for Epilepsy (LIFE)” symposium hosted by Cleveland Clinic
Theoretical and Experimental Evaluation of the Electronic Relaxation Mechanisms of 2-Pyrimidinone: The Primary UVA Absorbing Moiety of the DNA and RNA (6–4) Photolesion
Get PDFThe (6–4) photolesion is a key photodamage that occurs when two adjacent pyrimidine bases in a DNA strand bond together. To better understand how the absorption of UVB and UVA radiation by the 2-pyrimidinone moiety in a (6–4) lesion can damage DNA, it is important to study the electronic deactivation mechanism of its 2-pyrimidinone chromophore. This study employs theoretical (MS-CASPT2/cc-pVDZ level) and experimental (steady state and femtosecond broadband spectroscopic) methods to elucidate the photochemical relaxation mechanisms of 2-(1H)-pyrimidinone and 1-methyl-2-(1H)-pyrimidinone in aqueous solution (pH 7.4). In short, excitation at 320 nm leads to the population of the S11(ππ*) state with excess vibrational energy, which relaxes to the S11(ππ*) minimum in one picosecond or less. A trifurcation event in the S11(ππ*) minimum ensued, leading to radiative and nonradiative decay of the population to the ground state or the population of the long-lived and reactive T13(ππ*) state in hundreds of picoseconds. Collectively, the theoretical and experimental results support the idea that in DNA and RNA, the T13(ππ*) state of the 2-pyrimidinone moiety in the (6–4) lesion can further participate in photosensitized chemical reactions increasing DNA and RNA damage
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