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https://www.readbyqxmd.com/read/29679704/a-separable-two-dimensional-random-field-model-of-binary-response-data-from-multi-day-behavioral-experiments
#1
Noa Malem-Shinitski, Yingzhuo Zhang, Daniel T Gray, Sara N Burke, Anne C Smith, Carol A Barnes, Demba Ba
BACKGROUND: The study of learning in populations of subjects can provide insights into the changes that occur in the brain with aging, drug intervention, and psychiatric disease. NEW METHOD: We introduce a separable two-dimensional (2D) random field (RF) model for analyzing binary response data acquired during the learning of object-reward associations across multiple days. The method can quantify the variability of performance within a day and across days, and can capture abrupt changes in learning...
April 18, 2018: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/29679634/ex-vivo-mouse-brain-microscopy-at-15t-with-loop-gap-rf-coil
#2
Ouri Cohen, Jerome L Ackerman
The design of a loop-gap-resonator RF coil optimized for ex vivo mouse brain microscopy at ultra high fields is described and its properties characterized using simulations, phantoms and experimental scans of mouse brains fixed in 10% formalin containing 4 mM Magnevist™. The RF (B1 ) and magnetic field (B0 ) homogeneities are experimentally quantified and compared to electromagnetic simulations of the coil. The coil's performance is also compared to a similarly sized surface coil and found to yield double the sensitivity...
April 18, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29679498/7t-ultra-high-field-body-mr-imaging-with-an-8-channel-transmit-32-channel-receive-radiofrequency-coil-array
#3
Stefan H G Rietsch, Stephan Orzada, Stefan Maderwald, Sascha Brunheim, Bart W J Philips, Tom W J Scheenen, Mark E Ladd, Harald H Quick
PURPOSE: In this work a combined body coil array with 8 transmit/receive (Tx/Rx) meander elements and with 24 receive-only (Rx) loops (8Tx/32Rx) was developed and evaluated in comparison to an 8-channel transmit/receive body array (8Tx/Rx) based on meander elements serving as the reference standard. METHODS: Systematic evaluation of the RF array was performed on a body-sized phantom. Body imaging at 7T was performed in 6 volunteers in the body regions pelvis, abdomen, and heart...
April 21, 2018: Medical Physics
https://www.readbyqxmd.com/read/29679219/rf-ablation-pattern-shaping-employing-switching-channels-of-dual-bipolar-needle-electrodes-ex-vivo-results
#4
Jens Ziegle, Chloé Audigier, Johannes Krug, Ghazanfar Ali, Younsu Kim, Emad M Boctor, Michael Friebe
PURPOSE: Radiofrequency (RF) ablation with mono- or bipolar electrodes is a common procedure for hepatocellular carcinoma (HCC) with a low rate of recurrence for small size tumors. For larger lesions and/or non-round/ellipsoid shapes RF ablation has some limitations and generally does not achieve comparable success rates to microwave ablation or high-intensity focused ultrasound therapies. MATERIALS AND METHODS: To shape RF ablations for matching a tumor size and geometry, we have developed an electronic channel switch box for two bipolar needles that generates multiple selectable ablation patterns...
April 20, 2018: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/29678784/feasibility-safety-and-efficacy-of-a-novel-pre-shaped-nitinol-esophageal-deviator-to-successfully-deflect-the-esophagus-and-ablate-left-atrium-without-esophageal-temperature-rise-during-atrial-fibrillation-ablation-the-deflect-gut-study
#5
Valay Parikh, Vijay Swarup, Jacob Hantla, Venkat Vuddanda, Tawseef Dar, Bharath Yarlagadda, Luigi Di Biase, Amin Al-Ahmad, Andrea Natale, Dhanunjaya Lakkireddy
BACKGROUND: Esophageal thermal injury is a feared complication of radiofrequency ablation (RFA) for atrial fibrillation (AF). Rise in luminal esophageal temperature (LET) limits the ability to deliver RF energy on posterior wall of LA. OBJECTIVE: The aim of this registry was to evaluate feasibility, safety and efficacy of a mechanical esophageal deviation (ED) tool during AF ablation. METHODS: We evaluated 687 patients who underwent RFA for AF...
April 17, 2018: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/29678764/relation-of-nnos-isoforms-to-mitochondrial-density-and-pgc-1alpha-expression-in-striated-muscles-of-mice
#6
Oliver Baum, Dea Aaldijk, Anna Lena Engeli, Matthias Spree, Serge Summermatter, Christoph Handschin, Andreas Zakrzewicz
The expression of neuronal NO synthase (nNOS) alpha- and beta-isoforms in skeletal muscle is well documented but only little information is available about their regulation/functions. Using different mouse models, we now assessed whether the expression of nNOS-isoforms in muscle fibers is related to mitochondria content/activity and regulated by peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha). Catalytic histochemistry revealed highest nNOS-concentrations to be present in type-2 oxidative muscle fibers...
April 17, 2018: Nitric Oxide: Biology and Chemistry
https://www.readbyqxmd.com/read/29678603/chebulagic-acid-chebulinic-acid-and-gallic-acid-the-active-principles-of-triphala-inhibit-tnf%C3%AE-induced-pro-angiogenic-and-pro-inflammatory-activities-in-retinal-capillary-endothelial-cells-by-inhibiting-p38-erk-and-nfkb-phosphorylation
#7
Sivasankar Shanmuganathan, Narayanasamy Angayarkanni
Tumor necrosis factor-α (TNFα) a pleiotropic cytokine induces pro-inflammatory and pro-angiogenic changes in conditions such as diabetic retinopathy (DR) and neovascular age related macular degeneration (NV-AMD). Hence, inhibition of TNFα mediated changes can benefit the management of DR and NV-AMD. Triphala, an ayurvedic herbal preparation is known to have immunomodulatry functions. In this study we evaluated the alcoholic extract of triphala (AlE) and its compounds Chebulagic acid (CA), Chebulinic acid (CI) and Gallic acid (GA) for their anti-TNFα activity...
April 17, 2018: Vascular Pharmacology
https://www.readbyqxmd.com/read/29678541/b-1-non-uniformity-correction-of-phased-array-coils-without-measuring-coil-sensitivity
#8
Frederick C Damen, Kejia Caic
Parallel imaging can be used to increase SNR and shorten acquisition times, albeit, at the cost of image non-uniformity. B1 - non-uniformity correction techniques are confounded by signal that varies not only due to coil induced B1 - sensitivity variation, but also the object's own intrinsic signal. Herein, we propose a method that makes minimal assumptions and uses only the coil images themselves to produce a single combined B1 - non-uniformity-corrected complex image with the highest available SNR. A novel background noise classifier is used to select voxels of sufficient quality to avoid the need for regularization...
April 17, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29678186/should-fluid-dynamics-be-included-in-computer-models-of-rf-cardiac-ablation-by-irrigated-tip-electrodes
#9
Ana González-Suárez, Juan J Pérez, Enrique Berjano
BACKGROUND: Although accurate modeling of the thermal performance of irrigated-tip electrodes in radiofrequency cardiac ablation requires the solution of a triple coupled problem involving simultaneous electrical conduction, heat transfer, and fluid dynamics, in certain cases it is difficult to combine the software with the expertise necessary to solve these coupled problems, so that reduced models have to be considered. We here focus on a reduced model which avoids the fluid dynamics problem by setting a constant temperature at the electrode tip...
April 20, 2018: Biomedical Engineering Online
https://www.readbyqxmd.com/read/29677944/applications-of-machine-learning-in-fatty-live-disease-prediction
#10
Md Mohaimenul Islam, Chieh-Chen Wu, Tahmina Nasrin Poly, Hsuan-Chia Yang, Yu-Chuan Jack Li
: Fatty liver disease (FLD) is considered the most prevalent form of chronic liver disease worldwide. The prediction of fatty liver disease is an important factor for effective treatment and reduce serious health consequences. We, therefore construct a prediction model based on machine learning algorithms. A dataset was developed with ten attributes that included 994 liver patients in which 533 patients were females and others were male. Random Forest (RF), Support Vector Machine (SVM), Artificial Neural Network (ANN), and Logistic Regression (RF) data mining technique with 10-fold cross-validation was used in the proposed model for the prediction of fatty liver disease...
2018: Studies in Health Technology and Informatics
https://www.readbyqxmd.com/read/29677832/development-and-performance-analysis-of-carbon-nanowall-based-mass-sensor
#11
Seok Hun Kwon, Hyung Jin Kim, Won Seok Choi, Hyunil Kang
In this study, a mass sensor was fabricated using a carbon nanowalls, and its performance was analyzed. The substrate that was used to fabricate the mass sensor was a polyimide film, on which a SiO2 insulating layer and a copper electrode were deposited using an RF magnetron sputter. Thereafter, a carbon nanowalls was grown on the substrate until its size was 5 by 5 mm. The growth times of the completely grown carbon nanowalls were 20, 25, and 30 minutes, respectively. The performance of the mass sensors fabricated based on different carbon nanowalls grown for various growth times was analyzed according to the changing mass from 1 to 5 mg...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677828/influence-of-post-heat-treatment-of-zno-al-transparent-electrode-for-copper-indium-gallium-selenide-thin-film-solar-cell
#12
Taewoo Eom, Jeong Eun Park, Sang Yong Park, Jeong Hoon Park, Jackson Bweupe, Donggun Lim
Copper indium gallium selenide (CIGS) thin film solar cells have been regarded as a candidate for energy conversion devices owing to their high absorption coefficient, high temperature stability, and low cost. ZnO:Al thin film is commonly used in CIGS solar cells as a window layer. In this study, ZnO:Al films were deposited on glass under various post-heat temperature using RF sputtering to observe the characteristics of ZnO:Al films such as Hall mobility, carrier concentration, and resistivity; subsequently, the ZnO:Al films were applied to a CIGS solar cell as a window...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677810/al-ga-doped-zno-window-layers-for-highly-efficient-cu%C3%A2-znsn-s-se-%C3%A2-thin-film-solar-cells
#13
Se Won Seo, Jung Woo Seo, Donghwan Kim, Ki-Beom Cheon, Doh-Kwon Lee, Jin Young Kim
The successful use of Al-/Ga-doped ZnO (AGZO) thin films as a transparent conducting oxide (TCO) layer of a Cu2ZnSn(S,Se)4 (CZTSSe) thin film solar cell is demonstrated. The AGZO thin films were prepared by radio frequency (RF) sputtering. The structural, crystallographic, electrical, and optical properties of the AGZO thin films were systematically investigated. The photovoltaic properties of CZTSSe thin film solar cells incorporating the AGZO-based TCO layer were also reported. It has been found that the RF power and substrate temperature of the AGZO thin film are important factors determining the electrical, optical, and structural properties...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677777/a-study-on-the-formation-of-2-dimensional-tungsten-disulfide-thin-films-on-sapphire-substrate-by-sputtering-and-high-temperature-rapid-thermal-processing
#14
Hanyeob Nam, Hong-Seok Kim, Jae-Hee Han, Sang Jik Kwon, Eou Sik Cho
As direct formation of p-type two-dimensional transition metal dichalcogenides (TMDC) films on substrates, tungsten disulfide (WS2) thin films were deposited onto sapphire glass substrate through shadow mask patterns by radio-frequency (RF) sputtering at different sputtering powers ranging from 60 W to 150 W and annealed by rapid thermal processing (RTP) at various high temperatures ranging from 500 °C to 800 °C. Based on scanning electron microscope (SEM) images and Raman spectra, better surface roughness and mode dominant E12g and A1g peaks were found for WS2 thin films prepared at higher RF sputtering powers...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677738/improvement-of-electrical-properties-of-carbon-nanowall-by-the-deposition-of-thin-film
#15
Jong Kug Park, Hyunil Kang, Jung Hyun Kim, Wonseok Choi
In this study, the improvement of the electrical properties of carbon nanowalls (CNWs) by the deposition of nonmetallic thin films such as carbon (C), silicon (Si), and silicon carbide (SiC) was investigated. The CNWs were synthesized on a Si wafer substrate using microwave-plasma-enhanced chemical vapor deposition (PECVD). The thin films were deposited through RF magnetron sputtering with a 4-inch target (C, Si, and Sic) on the grown CNWs. The surficial and cross-sectional conditions were examined using the images obtained from a field emission scanning electron microscope (FESEM)...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677724/wide-bandgap-transparent-conducting-electrode-of-fto-ag-fto-structure-for-ultraviolet-light-emitting-diodes
#16
Gyu-Jae Yohn, Soae Jeong, Soo-Hyun Kang, Si-Won Kim, Beom-Rae Noh, Semi Oh, Bong-Yong Jeong, Kyoung-Kook Kim
We investigated the effect of the Ag interlayer thickness on the structural, electrical and optical properties of FTO/Ag/FTO structures designed for use in wide bandgap transparent conducting electrodes. The top and bottom FTO layers were deposited on α-Al2O3 (0001) substrates via RF magnetron sputtering at 300 °C and Ag interlayers were deposited using an e-beam evaporator system. We optimized the figure of merit by changing the thickness of the inserted Ag interlayer from 10 nm to 14 nm, achieving a maximum value of 2...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677708/chemical-vapor-deposition-carbon-film-as-a-capping-layer-in-4h-sic-based-mosfets
#17
Kyeong-Keun Choi, Jeong-Yoon Lee, Won-Beom Lee, Deok-Kee Kim, Chan-Gyung Park
Radio-frequency plasma enhanced CVD (RF-PECVD) carbon films were grown directly on 4-inch 4H-SiC substrates as a capping layer for MOSFET device applications. An approximately 50-nm-thick CVD carbon capping layer was found to reduce the surface roughness, as determined by atomic force microscopy (AFM). The secondary ion mass spectroscopy (SIMS) depth profile results revealed that carbon capping layer can suppress the dopant out-diffusion on the implanted surface after annealing even at high temperature (1700 °C) for 30 min...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677707/thermal-analysis-of-algan-gan-high-electron-mobility-transistor-and-its-rf-power-efficiency-optimization-with-source-bridged-field-plate-structure
#18
Hyeon-Tak Kwak, Seung-Bo Chang, Hyun-Gu Jung, Hyun-Seok Kim
In this study, we consider the relationship between the temperature in a two-dimensional electron gas (2-DEG) channel layer and the RF characteristics of an AlGaN/GaN high-electron-mobility transistor by changing the geometrical structure of the field-plate. The final goal is to achieve a high power efficiency by decreasing the channel layer temperature. First, simulations were performed to compare and contrast the experimental data of a conventional T-gate head structure. Then, a source-bridged field-plate (SBFP) structure was used to obtain the lower junction temperature in the 2-DEG channel layer...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677664/age-induced-changes-in-the-lower-limb-muscle-activities-during-uphill-walking-at-steep-grades
#19
Sonja Th Kwee-Meier, Alexander Mertens, Sabina Jeschke
BACKGROUND: Uphill walking is particularly challenging for elderly persons. However, there is a lack of age-differentiated studies investigating the underlying differences in muscle activation when walking on sloped surfaces. These studies are needed, e.g., for planning of evacuations of large modern cruise ships with long walking distances on often inclined surfaces. METHODS: An age-differentiated, gender-balanced study with 26 young (20-30 years) and 26 elderly people (60-77 years) was therefore conducted, investigating uphill walking at 7° and at 14° contrasted to level walking on a treadmill...
April 12, 2018: Gait & Posture
https://www.readbyqxmd.com/read/29677636/aunp-rf-sensor-an-innovative-application-of-rf-technology-for-sensing-pathogens-electrically-in-liquids-spel-within-the-food-supply-chain
#20
Leann Lerie Matta, Saranraj Karuppuswami, Premjeet Chahal, Evangelyn C Alocilja
Rapid detection techniques of pathogenic bacteria in the liquid food supply chain are of significant research interest due to their pivotal role in preventing foodborne outbreaks, and in maintaining high standards of public health and safety. Milk and dairy products are of particular interest due to their widespread consumption across the globe. In this paper, a biosensor for detecting pathogenic bacteria in milk using dextrin-capped gold nanoparticles (d-AuNP) as labels decoded at microwave frequencies is presented...
April 11, 2018: Biosensors & Bioelectronics
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