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Lee Kang Jea - - 2014
Light extraction efficiency of GaN-based light emitting diodes were significantly enhanced using silver nanostructures incorporated in periodic micro-hole patterned multi quantum wells (MQWs). Our results show an enhancement of 60% in the wall-plug efficiency at an injection current of 100 mA when Ag nano-particles were deposited on side facet of ...
Kim Do-Hyun - - 2014
We report on the improvement of light extraction efficiency from GaN-based light-emitting diodes (LEDs) using Ni<sub>1-x</sub>Co<sub>x</sub>O nanoparticles (NPs) formed on the p-GaN layer. After formation of Ni<sub>1-x</sub>Co<sub>x</sub>O hemispherical lens arrays on the blue LEDs by drop-casting colloidal NPs, electroluminescence (EL) and photoluminescence (PL) measurements are conducted to investigate the electrical ...
Wei Tongbo - - 2014
Homoepitaxially grown InGaN/GaN light emitting diodes (LEDs) with SiO<sub>2</sub> nanodisks embedded in n-GaN and p-GaN as photonic crystal (PhC) structures by nanospherical-lens photolithography are presented and investigated. The introduction of SiO<sub>2</sub> nanodisks doesn't produce the new dislocations and doesn't also result in the electrical deterioration of PhC LEDs. The light ...
Lee Kwang Jae - - 2014
We demonstrate the high efficiency of InGaN/GaN multiple quantum wells (MQWs) light-emitting diode (LED) grown on the electrochemically etched nanoporous (NP) GaN. The photoluminescence (PL) and Raman spectra show that the LEDs with NP GaN have a strong carrier localization effect resulting from the relaxed strain and reduced defect density ...
Liang Na - - 2014
Ag2O/Bi2O2CO3 p-n heterojunctions are prepared with commercial Bi2O2CO3 as precursor via a simple photosynthesis process. The obtained Ag2O/Bi2O2CO3 p-n heterojunctions show higher photocatalytic activity than that of pure n-Bi2O2CO3, and the obtained Ag2O/Bi2O2CO3 (AB-4) heterojunction exhibits the best photocatalytic activity under visible light (λ > 400 nm), with which Rhodamine ...
Patra Saroj Kanta - - 2014
In this paper, we have made a clear differentiation among bandgap, diffraction, interference, and refraction effects in photonic crystal structures (PhCs). For observing bandgap, diffraction, and refraction effects, PhCs are considered on the top p-GaN surface of light emitting diodes (LEDs), whereas for interference effect, hole type PhCs are considered ...
Natalini Paola M - - 2014
In this work, we describe a selective light-dependent distribution of the lipid kinase 1,2-diacylglycerol kinase (EC 2.7.1.107, DAGK) and the phosphorylated protein kinase C alpha (pPKCα) in a nuclear fraction of photoreceptor cells from bovine retinas. A nuclear fraction enriched in small nuclei from photoreceptor cells (PNF), was obtained when ...
Shin Jin-Wook - - 2014
In this study, we investigated the effect of a random nanostructure scattering layer (RSL) on the microcavity and light extraction in organic light emitting diodes (OLEDs). In the case of the conventional OLED, the optical properties change with the thickness of the hole transporting layer (HTL) because of the presence ...
Lee Jee-Bum JB Department of Dermatology, Chonnam National University Medical School and Hospital, Gwangju, 501-757, Korea (South), Republic - - 2014
Purpose: To investigate the effects of visible light on human corneal epithelial cells and the impact of natural antioxidants on oxidative stress produced by overexposure to light. Methods: Light-emitting diodes with various wavelengths (410-830 nm) were used to irradiate human corneal epithelial cells, and cell viability was assessed. The production ...
Wang Yong Y Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, 100083, People's Republic of - - 2014
Studies have shown that anthocyanins (ACNs) in berries contribute to eye health. However, information on the relationship between the chemical structures and visual functions of ACNs is scarce. This study investigated the protection effects of ACN with different structures against visible light-induced damage in human retinal pigment epithelial (RPE) cells. ...
Vale Ana Paula AP REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal; ESA, Instituto Politécnico de Viana do Castelo, Refóios do Lima, 4990-706 Ponte de Lima, - - 2014
The antioxidant activity of sprouts from four Brassica oleracea varieties was evaluated using "in vitro" methods (total phenolic and flavonoid content; radical scavenging assays: DPPH, hydroxyl and peroxyl; and Ferrous Ion-chelating Ability Assay). Light cycles and sprouting influenced the potential antioxidant activity of sprouts and significant differences were observed between ...
Shunmugam Sumathy - - 2014
Screening of 55 different cyanobacterial strains revealed that an extract from Nostoc XPORK14A drastically modifies the amplitude and kinetics of chlorophyll a fluorescence induction of Synechocystis PCC6803 cells.After 2 d exposure to the Nostoc XPORK14A extract, Synechocystis PCC 6803 cells displayed reduced net photosynthetic activity and significantly modified electron transport ...
Silies Marion M Department of Neurobiology, Stanford University, Stanford, CA 94305, - - 2014
How does the brain compare visual inputs over space and time to extract motion? Electron microscopic (EM) and molecular analyses reveal a new circuit architecture for motion processing in Drosophila. An offset in the weighting of synaptic connections and differential use of fast and slow nicotinic receptors suggests a mechanism ...
Lenef Alan - - 2014
An extension of a theorem for light extraction [Adv. Opt. Technol.2, 291 (2013)] from a higher index luminescent body (LED or phosphor) through an extracting surface into a lower index output medium is derived. The result is valid for both geometric and diffractive surface structures. Using this bound and radiation ...
Doufesh Hazem H 1 Department of Biomedical Engineering, Faculty of Engineering, University of Malaya , Kuala Lumpur, Malaysia - - 2014
Abstract Objectives: This study investigated the effect of Muslim prayer (salat) on the α relative power (RPα) of electroencephalography (EEG) and autonomic nervous activity and the relationship between them by using spectral analysis of EEG and heart rate variability (HRV). Methods: Thirty healthy Muslim men participated in the study. Their ...
Foussier Jerome - - 2014
Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task. The respiratory and cardiac signals are mixed on top of a large and time-varying offset and are likely to be disturbed by measurement noise. Basic filtering techniques fail to extract the relevant information ...
Wegehaupt Florian J - - 2014
Surface sealants have been successfully used in the prevention of erosive tooth wear. However, when multiple tooth surfaces should be sealed, the light-curing procedure is very time-consuming. Therefore, the aim of this study was to investigate whether reduced light-curing time (while maintaining similar energy density) has an influence on resin-based ...
Park Hyeong-Ho - - 2014
A new approach to surface roughening was established and optimized in this paper for enhancing the light extraction of high power AlGaInP-based LEDs, by combining ultraviolet (UV) assisted imprinting with dry etching techniques. In this approach, hexagonal arrays of cone-shaped etch pits are fabricated on the surface of LEDs, forming ...
Lee Jooyoung - - 2014
We investigate two types of internal light-extraction layer structures for organic light-emitting diodes (OLEDs) that consist of silica nanoparticles (NPs) embedded in high-refractive-index TiO<sub>2</sub> matrices. The composite of silica NPs and TiO<sub>2</sub> matrices was coated on the glass substrate and fabricated with and without a SiO<sub>2</sub> planarization layer. An increase ...
Huang Chun-Ying CY Institute of Electronics Engineering, National Taiwan University, 1, Sec. 4, Roosevelt Road, Taipei 106, - - 2014
In this work, local nanotip arrays on GaN-based light-emitting (LED) structures were fabricated through nano-oxidation using an atomic force microscope (AFM). The photoluminescence (PL) intensity of the InGaN/GaN multiple quantum wells (MQWs) active layer and the light extraction efficiency of the LED structure were enhanced by forming this nanotips structure ...
Peng Fulai - - 2014
The calculation of arterial oxygen saturation (SpO2) relies heavily on the amplitude information of the high-quality photoplethysmographic (PPG) signals, which could be contaminated by motion artifacts (MA) during monitoring. A new method combining temporally constrained independent component analysis (cICA) and adaptive filters is presented here to extract the clean PPG ...
Liu Yi - - 2014
We propose the use of compressive holography for two-dimensional (2D) subpixel motion localization. Our approach is based on computational implementation of edge-extraction using a Fourier-plane spiral phase mask, followed by compressive reconstruction of the edge of the object. Using this technique and relatively low-cost computer and piezo motion stage to ...
Giorgi Maria Cecília C MC Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas (UNICAMP), Avenida Limeira, 901 Bairro Areião, Piracicaba, SP, 13414-903, Brazil, - - 2014
The aim of this study was to evaluate the degree of conversion (DC) and to identify the viscoelastic properties: storage modulus (E'), loss modulus (E"), tangent delta (tan δ), and glass transition temperature (T g ) of a microhybrid resin-composite light-activated by three different protocols. A Filtek Z250 (3 M ESPE) ...
Zhang Yi - - 2014
The stimulus response of the classical receptive field (CRF) of neuron in primary visual cortex is affected by its periphery (i.e. non-CRF). This modulation exerts inhibition, which depends primarily on the correlation of both visual stimulations. The theory of periphery and center interaction with visual characteristics can be applied in ...
Ogawa Kenjirou - - 2014
Blue light is a high-energy or short-wavelength visible light, which induces retinal diseases such as age-related macular degeneration and retinitis pigmentosa. Bilberry (Vaccinium myrtillus L.) and lingonberry (Vaccinium vitis-idaea) contain high amounts of polyphenols (anthocyanins, resveratrol, and proanthocyanidins) and thus confer health benefits. This study aimed to determine the protective ...
Li Yansheng - - 2014
In this paper, a biologically inspired multilevel approach for simultaneously detecting multiple independently moving targets from airborne forward-looking infrared (FLIR) sequences is proposed. Due to the moving platform, low contrast infrared images, and nonrepeatability of the target signature, moving targets detection from FLIR sequences is still an open problem. Avoiding ...
Cia David D UMR Inserm 1107, Laboratoire de Biophysique Neurosensorielle, UFR Pharmacie, Clermont Université, Clermont-Ferrand, - - 2014
Aim: Most Duchenne muscular dystrophy patients and the mdx(Cv3) mouse strain, lacking expression of both dystrophins Dp260 and Dp71, show a high attenuation of the dark-adapted electroretinogram (ERG) b-wave amplitude, whereas mice lacking the expression of Dp260 show normal b-wave amplitude. Here, we completed our assessment of whether the sole ...
Jeong Hyun H Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea. - - 2014
We investigate the mechanism of light extraction enhancement of a GaN-based light-emitting diode (LED) grown on patterned sapphire substrate (PSS), that has ZnO nanorod arrays (NRAs) fabricated on top of the device using the hydrothermal method. We found that the light output power of the LED with ZnO NRAs increases ...
Borst Alexander A Max Planck Institute of Neurobiology, Systems and Computational Neuroscience , Martinsried , - - 2014
Detecting the direction of image motion is a fundamental component of visual computation and is essential for survival of the animal. However, at the level of the photoreceptors, the direction in which the image is shifting locally is not explicitly represented. Rather, directional motion information needs to be extracted from ...
Yousefi Rasoul - - 2014
The performance of portable and wearable biosensors is highly influenced by motion artifact. In this paper, a novel real-time adaptive algorithm is proposed for accurate motion-tolerant extraction of heart rate (HR) and pulse oximeter oxygen saturation ( SpO2) from wearable photoplethysmographic (PPG) biosensors. The proposed algorithm removes motion artifact due ...
Zeng Yang Y Institute of Solar Energy, and Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics, Shanghai Jiao Tong University, Shanghai 200240, - - 2014
We demonstrate improved short-wavelength internal quantum efficiency (IQE) of a-Si/c-Si heterojunction (HJ) solar cells with a surface nanopillar (NP) array via simulation. The gain in IQE is attributed to the light-field modulation caused by the cavity resonance inside the NPs, in which the light energy is effectively localized within the ...
Toft-Nielsen Jonathon J University of Miami, Dept. Biomedical Engineering, PO Box 248294, Coral Gables, FL 33124, United States; JÖRVEC Corp., Miami, FL, 6860 SW 81 St, Miami, FL 33143, United - - 2014
Due to overlapping, temporal information is mostly lost in high rate steady-state pattern electroretinograms (PERGSS). This study develops a deconvolution method and a display/recording system to "unwrap" PERGSS and obtain a transient, "per stimulus" response (PERGtr) regardless of reversal rate. Processing and instrumentation, including high temporal resolution display and acquisition ...
Churchill Tyler H TH Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue #521, Madison, WI, 53705, USA, - - 2014
A cochlear implant (CI) presents band-pass-filtered acoustic envelope information by modulating current pulse train levels. Similarly, a vocoder presents envelope information by modulating an acoustic carrier. By studying how normal hearing (NH) listeners are able to understand degraded speech signals with a vocoder, the parameters that best simulate electric hearing ...
Ahmad Nadzri Ahmad Akmal Bin AA Department of Electrical and Electronic Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia, - - 2014
Surface electromyography (SEMG) signals can provide important information for prosthetic hand control application. In this study, time domain (TD) features were used in extracting information from the SEMG signal in determining hand motions and stages of contraction (start, middle and end). Data were collected from ten healthy subjects. Two muscles, ...
Wei Tongbo - - 2014
Large-scale SiO<sub>2</sub> nanodisk arrays fabricated by nanospherical-lens lithography are embedded in the n-GaN and p-GaN layer of an InGaN/GaN light-emitting diode (LED) to produce photonic crystal (PC) structures for efficiency improvement. Following the obvious reduction of view angle, the light output power of bottom, top, and double PC LEDs is ...
Kim Jun-Whee - - 2014
The light extraction efficiency of OLEDs with a nano-sized random scattering layer (RSL-OLEDs) was analyzed using the Finite Difference Time Domain (FDTD) method. In contrast to periodic diffraction patterns, the presence of an RSL suppresses the spectral shift with respect to the viewing angle. For FDTD simulation of RSL-OLEDs, a ...
Horng Ray-Hua - - 2014
Light extraction of GaN-based light-emitting diodes grown on Si(111) substrate (GaN-on-Si based LEDs) is presented in this study. Three different designs of GaN-on-Si based LEDs with the lateral structure, lateral structure on mirror/Si(100) substrate, and vertical structure on mirror/Si(100) substrate were epitaxially grown by metalorganic chemical vapor deposition and fabricated ...
Singh Amritpal S AS Department of Plant Agriculture, University of Guelph, Guelph, ON, N1G 2W1, - - 2014
Thirty five commercial maple syrups from twelve producers in Southern Ontario were evaluated for properties including light transmittance, autofluorescence, density, pH, total soluble solids (TSS), glucose and fructose content, total phenol content, antioxidant potential and mineral content (Mg, Mn, P, Zn, Ca, K, Fe and Pb). A high degree of ...
Ludwig Casimir J H CJ School of Experimental Psychology, University of Bristol, Bristol BS8 1TU, United - - 2014
Human vision is an active process in which information is sampled during brief periods of stable fixation in between gaze shifts. Foveal analysis serves to identify the currently fixated object and has to be coordinated with a peripheral selection process of the next fixation location. Models of visual search and ...
Sabaikai Waraluk - - 2014
The UV light photo-Fenton degradation of oolong tea polyphenols in tea manufacturing effluent that color the wastewater to a dark brown has been examined. In order to elucidate the photo-Fenton degradation mechanism of oolong tea polyphenols and find the optimal dosages of the Fenton reagents, systematic study has been conducted. ...
Ye-Lin Yiyao Y Grupo de Bioelectrónica (I3BH), Universitat Politècnica de València, Camino de Vera s/n Ed.8B, 46022 Valencia, - - 2014
Electrohysterography (EHG) is a noninvasive technique for monitoring uterine electrical activity. However, the presence of artifacts in the EHG signal may give rise to erroneous interpretations and make it difficult to extract useful information from these recordings. The aim of this work was to develop an automatic system of segmenting ...
Ryu Han-Youl HY Department of Physics, Inha University, Incheon 402-751, Korea. - - 2014
Light extraction efficiency (LEE) of AlGaN-based nanorod deep ultraviolet (UV) light-emitting diodes (LEDs) is numerically investigated using three-dimensional finite-difference time-domain simulations. LEE of deep UV LEDs is limited by strong light absorption in the p-GaN contact layer and total internal reflection. The nanorod structure is found to be quite effective ...
Li Lu L 1] Department of Materials Sciences and Engineering, California NanoSystems Institute, Henry Samuli School of Engineering and Applied Science, University of California, Los Angeles, California 90095 - - 2014
Highly efficient organic light emitting diodes (OLEDs) based on multiple layers of vapor evaporated small molecules, indium tin oxide transparent electrode, and glass substrate have been extensively investigated and are being commercialized. The light extraction from the exciton radiative decay is limited to less than 30% due to plasmonic quenching ...
Sweetman Adam A The School of Physics and Astronomy, The University of Nottingham, Nottingham, NG7 2RD, - - 2014
In principle, non-contact atomic force microscopy (NC-AFM) now readily allows for the measurement of forces with sub-nanonewton precision on the atomic scale. In practice, however, the extraction of the often desired 'short-range' force from the experimental observable (frequency shift) is often far from trivial. In most cases there is a ...
Fernández-Caballero Antonio A Departamento de Sistemas Informáticos, Universidad de Castilla-La Mancha, 02071-Albacete, Spain. - - 2014
This paper investigates the robustness of a new thermal-infrared pedestrian detection system under different outdoor environmental conditions. In first place the algorithm for pedestrian ROI extraction in thermal-infrared video based on both thermal and motion information is introduced. Then, the evaluation of the proposal is detailed after describing the complete ...
Park Paul Shin-Hyun PS Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA. Electronic address: - - 2014
Rhodopsin is the light receptor in rod photoreceptor cells of the retina that initiates scotopic vision. In the dark, rhodopsin is bound to the chromophore 11-cis retinal, which locks the receptor in an inactive state. The maintenance of an inactive rhodopsin in the dark is critical for rod photoreceptor cells ...
Weise Annekathrin A Kognitive einschließlich Biologische Psychologie, Institut für Psychologie, Universität Leipzig Leipzig, - - 2014
The human central auditory system can automatically extract abstract regularities from a variant auditory input. To this end, temporarily separated events need to be related. This study tested whether the timing between events, falling either within or outside the temporal window of integration (~350 ms), impacts the extraction of abstract ...
Zhu Hong-Min HM Department of Computer and Information Science, University of Macau, - - 2014
We propose an adaptive and robust superpixel based hand gesture tracking system, in which hand gestures drawn in free air are recognized from their motion trajectories. First we employed the motion detection of superpixels and unsupervised image segmentation to detect the moving target hand using the first few frames of ...
Eugeni Piller Lucia L Laboratoire de Physiologie Végétale, Institute of Biology, Université de Neuchâtel Neuchâtel, - - 2014
Plants are exposed to ever changing light environments and continuously forced to adapt. Excessive light intensity leads to the production of reactive oxygen species that can have deleterious effects on photosystems and thylakoid membranes. To limit damage, plants increase the production of membrane soluble antioxidants such as tocopherols. Here, untargeted ...
Gauvin Mathieu M 0000-0002-8600-5982 Department of Ophthalmology & Neurology-Neurosurgery, Montreal Children's Hospital Research Institute, McGill University, 2300 Tupper Street, Montreal, QC, Canada H3H - - 2014
Purpose. To compare time domain (TD: peak time and amplitude) analysis of the human photopic electroretinogram (ERG) with measures obtained in the frequency domain (Fourier analysis: FA) and in the time-frequency domain (continuous (CWT) and discrete (DWT) wavelet transforms). Methods. Normal ERGs (n = 40) were analyzed using traditional peak ...
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