Plasma treatment of polymer dielectric films to improve capacitive energy storage

Demand for compact instrumentation, portable field equipment, and new electromagnetic weapons is creating a need for new dielectric materials with higher energy storage capabilities. Recognizing the need for higher energy storage capacitors, the Army Research Lab at Fort Monmouth, NJ, initiated a program a year ago to investigate potential methods for increasing the dielectric strength of polyvinylidene difluoride (PVDF) film, which is the highest energy density material commercially available today. Treatment of small area PVDF films in a CF4/O2 plasma showed that the dielectric strength of PVDF films can be increased by as much as 20 percent when treated in a 96 percent CF4/4 percent O2 plasma. This 44 percent increase in energy storage of a PVDF capacitor is significant considering that the treatment can be implemented in a conventional metallizing chamber, with minimum capital investment. The data shows that improved breakdown strength may be unique to PVDF film and the particular CF4/O2 gas mixture, because PVDF film treated with 100 percent CF4, 100 percent O2, Ar gas plasma, and electron irradiation shows no improvement in breakdown strength. Other data presented includes dissipation factor, dielectric constant, and surface tension measurements

Characterization of the novel spontaneously immortalized rat Müller cell line SIRMu-1

Müller cells (MCs) play a crucial role in the retina, and cultured MC lines are an important tool with which to study MC function. Transformed MC lines have been widely used; however, the transformation process can also lead to unwanted changes compared to the primary cells from which they were derived. To provide an alternative experimental tool, a monoclonal novel spontaneously immortalized rat Müller cell line, SIRMu-1, was derived from primary rat MCs and characterized. Immunofluorescence, western blotting and RNA sequencing demonstrate that the SIRMu-1 cell line retains similar characteristics to cultured primary MCs in terms of expression of the MC markers cellular retinaldehyde-binding protein, glutamine synthetase, S100, vimentin and glial fibrillary acidic protein at both the mRNA and protein levels. Both the cellular morphology and overall transcriptome of the SIRMu-1 cells are more similar to primary rat MCs than the commonly used rMC-1 cells, a well-described, transformed rat MC line. Furthermore, SIRMu-1 cells proliferate rapidly, have an effectively indefinite life span and a high transfection efficiency. The expression of Y chromosome specific genes confirmed that the SIRMu-1 cells are derived from male MCs. Thus, the SIRMu-1 cell line represents a valuable experimental tool to study roles of MCs in both physiological and pathological states.Thaksaon Kittipassorn, Cameron D. Haydinger, John P.M. Wood, Teresa Mammone, Robert J. Casson, Daniel J. Pee

RNA sequencing data of cultured primary rat Muller cells, the spontaneously immortalized rat Muller cell line, SIRMu-1, and the SV40-transformed rat Muller cell line, rMC-1

Available online 7 March 2019Müller cells (MCs), the major type of glial cell of the vertebrate retina, have a vital role in retinal physiology and pathology. They provide structural and functional support for retinal neurons, including photoreceptors, and are implicated in various retinal diseases. Primary and immortalized MCs are important experimental tools for MC research. Here we present high throughput RNA sequencing data of 3 populations of cultured rat MCs: primary cells, the spontaneously immortalized rat MC line, SIRMu-1, and the SV40-transformed rat MC line, rMC-1. These data were deposited in NCBI Gene Expression Omnibus (GEO ID: GSE123161). For data analysis, interpretation and discussion, please refer to the research article, “Characterization of the novel spontaneously immortalized rat Müller cell line SIRMu-1” (Kittipassorn et al., 2019). This dataset is valuable for gaining insight into gene expression profiles of different types of cultured MCs and the roles of MCs in health and disease.Thaksaon Kittipassorn, Cameron D. Haydinger, John P.M. Wood, Teresa Mammone, Robert J. Casson, Daniel J. Pee

Assisted Diagnosis of Parkinsonism Based on the Striatal Morphology

Parkinsonism is a clinical syndrome characterized by the progressive loss of striatal dopamine. Its diagnosis is usually corroborated by neuroimaging data such as DaTSCAN neuroimages that allow visualizing the possible dopamine deficiency. During the last decade, a number of computer systems have been proposed to automatically analyze DaTSCAN neuroimages, eliminating the subjectivity inherent to the visual examination of the data. In this work, we propose a computer system based on machine learning to separate Parkinsonian patients and control subjects using the size and shape of the striatal region, modeled from DaTSCAN data. First, an algorithm based on adaptative thresholding is used to parcel the striatum. This region is then divided into two according to the brain hemisphere division and characterized with 152 measures, extracted from the volume and its three possible 2-dimensional projections. Afterwards, the Bhattacharyya distance is used to discard the least discriminative measures and, finally, the neuroimage category is estimated by means of a Support Vector Machine classifier. This method was evaluated using a dataset with 189 DaTSCAN neuroimages, obtaining an accuracy rate over 94%. This rate outperforms those obtained by previous approaches that use the intensity of each striatal voxel as a feature.This work was supported by the MINECO/ FEDER under the TEC2015-64718-R project, the Ministry of Economy, Innovation, Science and Employment of the Junta de Andaluc´ıa under the P11-TIC-7103 Excellence Project and the Vicerectorate of Research and Knowledge Transfer of the University of Granada

Open Problems on Central Simple Algebras

We provide a survey of past research and a list of open problems regarding central simple algebras and the Brauer group over a field, intended both for experts and for beginners.Comment: v2 has some small revisions to the text. Some items are re-numbered, compared to v

First-principles calculations of the phase stability of TiO2

Published versio

A tomographic analysis of reflectometry data I: Component factorization

Many signals in Nature, technology and experiment have a multi-component structure. By spectral decomposition and projection on the eigenvectors of a family of unitary operators, a robust method is developed to decompose a signals in its components. Different signal traits may be emphasized by different choices of the unitary family. The method is illustrated in simulated data and on data obtained from plasma reflectometry experiments in the tore Supra.Comment: 27 pages Latex, 17 figure

Through-Thickness Residual Stress Profiles in Austenitic Stainless Steel Welds: A Combined Experimental and Prediction Study

Economic and safe management of nuclear plant components relies on accurate prediction of welding-induced residual stresses. In this study, the distribution of residual stress through the thickness of austenitic stainless steel welds has been measured using neutron diffraction and the contour method. The measured data are used to validate residual stress profiles predicted by an artificial neural network approach (ANN) as a function of welding heat input and geometry. Maximum tensile stresses with magnitude close to the yield strength of the material were observed near the weld cap in both axial and hoop direction of the welds. Significant scatter of more than 200 MPa was found within the residual stress measurements at the weld center line and are associated with the geometry and welding conditions of individual weld passes. The ANN prediction is developed in an attempt to effectively quantify this phenomenon of ‘innate scatter’ and to learn the non-linear patterns in the weld residual stress profiles. Furthermore, the efficacy of the ANN method for defining through-thickness residual stress profiles in welds for application in structural integrity assessments is evaluated

Transnational partisanship: idea and practice

That parties might successfully organize transnationally is an idea often met with scepticism. This article argues that while certain favourable conditions are indeed absent in the transnational domain, this implies not that partisanship is impossible but that it is likely to be marked by certain traits. Specifically, it will tend to be episodic, structured as a low-density network and delocalized in its ideational content. These tendencies affect the normative expectations one can attach to it. Transnational partisanship should be valued as a transitional phenomenon, e.g. as a pathway to transnational democracy, more than as a desirable thing in itself