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Chi Jim-Yong - - 2009
A packaging scheme utilizing omni-directional reflective (ODR) optical coating is described to enhance the light extraction of near UV excited, phosphor-converted LEDs. A simple 1D model was developed to analyze the spectra of the extracted light measured with an integration-sphere as a function of phosphor layer concentration and thickness. Quantitative ...
Tan T Y - - 2009
To determine the correlation between hypertensive retinopathy (which is the end-organ damage of the vessels due to chronic hypertension) with sensorineural hearing loss. Pure tone hearing threshold of 56 hypertensive patients were compared with 56 normal age and sex matched control. Comparisons of pure tone hearing threshold are made among ...
Kwon Young Soo - - 2009
A series of seven diarylaminofluorene-derived fluorescent molecules demonstrating a blue emission in organic light-emitting diodes (OLEDs) were synthesized via the Horner-Wadsworth-Emmons reaction and the Suzuki-cross coupling reaction. Among the molecules, one device exhibited blue emission with a maximum luminance of 28900 cd/m2 at 12 V. A luminous efficiency of 11.5 ...
Dragnea Vladimira V Departments of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, - - 2009
Previous crystallographic studies of the AppA BLUF domain indicated that Trp104 is capable of undertaking alternate conformations depending on the length of the BLUF domain. A BLUF domain containing a C-terminal deletion (AppA1-126) reveals that Trp104 is partially solvent exposed while a BLUF domain containing a slightly longer carboxyl terminal ...
Brydegaard Mikkel - - 2009
We investigate the possibilities of light detection and ranging (lidar) techniques to study migration of the damselfly species Calopteryx splendens and C. virgo. Laboratory and testing-range measurements at a distance of 60 m were performed using dried, mounted damselfly specimens. Laboratory measurements, including color photography in polarized light and spectroscopy ...
Antal T K - - 2009
High-resolution light-induced kinetics of chlorophyll fluorescence (OJIP transients) were recorded and analyzed in cultures of diatoms (Thalassiosira weissflogii, Chaetoceros mulleri) and dinoflagellates (Amphidinium carterae, Prorocentrum minimum). Fluorescence transients showed the rapid exponential initial rise from the point O indicating low connectivity between PS II units and high absorption cross-section of ...
Larsen Hanne H Nofima Mat AS-Norwegian Inst. of Food, Fisheries and Aquaculture Research, Osloveien 1, NO-1430 As, Norway. - - 2009
In this study, photooxidation of sour cream packaged in cups with different light barrier properties was investigated. The sour cream was light exposed for 36 h with a standard fluorescent light tube, simulating storage conditions in many Norwegian grocery stores. Three different cups were evaluated: a white cup, a cup ...
Lee J H - - 2009
Effects of fluorescent light, riboflavin, ascorbic acid, sodium azide, and butylated hydroxyanisole (BHA) on the volatiles in milk at 4 degrees C were determined using a combination of headspace-solid phase microextraction (HS-SPME), gas chromatography (GC), and mass spectrometry (MS). Pentanal, hexanal, heptanal, and dimethyl disulfide were formed only in the ...
Zirak P - - 2009
The wild-type BLUF protein Slr1694 from Synechocystis sp. PCC6803 (BLUF=blue-light sensor using FAD) has flavin adenosine dinucleotide (FAD) as natural cofactor. This light sensor causes positive phototaxis of the marine cyanobacterium. In this study the FAD cofactor of the wild-type Slr1694 was replaced by roseoflavin (RoF) and the roseoflavin derivatives ...
Xiao F - - 2009
Y(4)MgSi(3)O(13):Bi(3+), Eu(3+) nanophosphors have been prepared by a facile sol-gel method. The products have been characterized by X-ray diffraction, field-emission scanning electron microscopy and fluorescence measurements. The results show that the nanophosphors are of single phase hexagonal Y(4)MgSi(3)O(13) with size-distribution of 50-90 nm in diameter. White-light emission has been obtained ...
Trusov Alexander - - 2009
DESIGN: Cross-sectional studies in Russia (n = 502) and Macedonia (n = 205), with fluorochrome-stained sputum examined by 1) the new Lumin light emitting diode (LED) fluorescent attachment on a light microscope, and 2) conventional fluorescent microscope (CFM) available in each laboratory, and compared to 3) Ziehl-Neelsen (ZN) restaining/reading of ...
Hong Yuning - - 2009
It is textbook knowledge that chromophore aggregation generally quenches light emission. In this feature article, we give an account on how we observed an opposite phenomenon termed aggregation-induced emission (AIE) and identified the restriction of intramolecular rotation as a main cause for the AIE effect. Based on the mechanistic understanding, ...
Uematsu T - - 2009
Photoetching of CdTe nanocrystals was applied to thiol-capped CdTe quantum dots (QDs) to control their fluorescence wavelength. CdTe QDs with a high quantum yield (49%) were synthesized in aqueous solution, and they were successfully photoetched in strong alkaline (pH = 13.5) conditions. When monochromatic light was used, size-selective photoetching could ...
Gioux Sylvain S Division of Hematology/Oncology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, - - 2009
Optical imaging requires appropriate light sources. For image-guided surgery, in particular fluorescence-guided surgery, a high fluence rate, a long working distance, computer control, and precise control of wavelength are required. In this article, we describe the development of light-emitting diode (LED)-based light sources that meet these criteria. These light sources ...
Sinha Sudarson Sekhar - - 2009
In this work we describe design and use of a fiber-optic based optical system for the spectroscopic studies on the samples under the presence of strong ambient light. The system is tested to monitor absorption, emission, and picosecond-resolved fluorescence transients simultaneously with a time interval of 500 ms for several ...
Bowers Michael J MJ - - 2009
White-light emission from ultrasmall CdSe nanocrystals offers an alternative approach to the realization of solid-state lighting as an appealing technology for consumers. Unfortunately, their extremely small size limits the feasibility of traditional methods for nanocrystal characterization. This paper reports the first images of their structure, which were obtained using aberration-corrected ...
Endoh Tamaki - - 2009
In this study we describe the spatial regulation of RNA interference (RNAi) using an RNA-carrier protein labeled with a fluorescent dye and a light source to trigger the RNAi. We demonstrate photo-dependent gene silencing using several dyes with different excitation wavelengths. Additionally, we use light from a halogen lamp and ...
Carbonaro Carlo M - - 2009
The spectral properties of postdoping prepared type I Rhodamine 6G-silica hybrids were investigated in the case of intentionally large doping (5 x 10(-2) mol/L). Beside expected concentration quenching effects, steady state and time resolved optical spectroscopy measurements displayed the presence of different kind of aggregates, both fluorescent and nonfluorescent. As ...
Pei Renjun - - 2009
The full understanding of dynamics of cellular processes hinges on the development of efficient and non-invasive labels for intracellular RNA species. Light-up aptamers binding fluorogenic ligands show promise as specific labels for RNA species containing those aptamers. Herein, we took advantage of existing, non-light-up aptamers against small molecules and demonstrated ...
Tan Han Yen - - 2009
Appropriate monochromatic illumination that is spatially uniform will ensure densitometry of stained polyacrylamide electrophoresis gels with high sensitivity and repeatability. The approach of using an array of LEDs as an illuminator has practical limitations. Here we describe an alternative method based on adapted liquid crystal display backlighting. By changing the ...
Dige I - - 2009
INTRODUCTION: Quantative confocal laser scanning microscopy (CLSM) in combination with fluorescent in situ hybridization (FISH) may help to increase our knowledge about biofilm formation. The purpose of this study was to develop and evaluate a stereological method for quantification of bacteria in intact biofilm. The method was applied in a ...
Andréasson Joakim - - 2009
Off and on: A molecular triad, consisting of a porphyrin linked to two different, independently addressable photochromic moieties, functions as a molecular keypad lock with all-photonic inputs and output. The porphyrin correlates the responses of the two inputs to light of different wavelengths and provides an appropriate output as fluorescence, ...
Corbitt Thomas S - - 2009
Microcapsules consisting of alternating layers of oppositely charged poly(phenylene ethynylene)-type conjugated polyelectrolytes (CPEs) were prepared via layer-by-layer deposition onto MnCO3 template particles followed by dissolution of the template particles using an ethylenediaminetetraacetate solution. The resulting microcapsules exhibit bright-green fluorescence emission characteristics of the CPEs. Strong antimicrobial activity was observed upon ...
Herman Tobias K - - 2009
Single molecule fluorescence experiments, with their associated low signals, require very low background fluorescence in the sample. Even high purity liquids will often possess large numbers of fluorescent impurities that are difficult to completely remove through standard purification techniques such as distillation and recrystallization. We have constructed a simple setup ...
Terrer Elodie - - 2009
AIM: The objective of this in vivo experiment is to propose an innovative therapeutic concept using a light-induced fluorescence evaluator for diagnosis and treatment (LIFEDT) that is based on the imaging and autofluorescence of dental tissues. BACKGROUND: Processes with the aim of diagnosing carious lesions in the initial stage with ...
Wold Jens Petter - - 2009
The effect of headspace oxygen concentration and color of light on photo-oxidation and degradation of photosensitizers in butter was studied. Butter samples were stored under 0%, 0.4%, 0.8%, 1.6%, 3.0%, 5.0%, 21% oxygen, and exposed to violet, green or red light. Storage time was 36 h. Degree of photo-oxidation was ...
Zhao Yan-Li - - 2008
A pyrene-modified beta-cyclodextrin (pyrenecyclodextrin)-decorated single-walled carbon nanotube (SWNT) field-effect transistor (FET) device was fabricated, which can serve as a tunable photosensor to sense a fluorescent adamantyl-modified Ru complex (ADA-Ru). When the light is on (I = 40 W m(-2) and lambda = 280 nm), the transfer curve of the pyrenecyclodextrin-SWNT/FET ...
Keller Philipp J - - 2008
The observation of biological processes in their natural in vivo context is a key requirement for quantitative experimental studies in the life sciences. In many instances, it will be crucial to achieve high temporal and spatial resolution over long periods of time without compromising the physiological development of the specimen. ...
Macko Peter - - 2008
An approach to enhancing the light collection from fluorescence emitters bound on the surface of a biochip is presented. It is based on the integration of diffractive optical elements on the underside of the chip that are essentially thick volume holograms written into a layer of photopolymer recording material. The ...
Tsuei Chih-Hsuan - - 2008
In this study we simulate the illuminance and efficiency of four different types of reflector LED and fluorescent light sources for interior illumination. According to our calculation results of the examination of simulations and real situations, we find that the LEDs do perform better than fluorescent lights. We also consider ...
Thacker S A - - 2008
The functional properties of dissolved organic matter (DOM) from Rough Sike, a stream draining blanket peat in the northern Pennines, UK, were investigated using a series of 12 standardised assays. Nine stream samples were collected at different discharges during 2003--2006, and DOM concentrates obtained by low temperature rotary evaporation. Suwannee ...
Brock Matthias - - 2008
Aspergillus fumigatus is the main cause of invasive aspergillosis in immunocompromised patients, and only a limited number of drugs for treatment are available. A screening method for new antifungal compounds is urgently required, preferably an approach suitable for in vitro and in vivo studies. Bioluminescence imaging is a powerful tool ...
Tan Han Yen - - 2009
We describe a novel approach for fluorometry with light-emitting-diodes (LEDs) as excitation source that capitalizes on the principle of light shielding and total internal reflection to operate without optical filters. This scheme is practicable, demonstrated to significantly reduce the amount of excitation light overlapping the fluorescence signals at the photodetector, ...
Marjono Andhi - - 2008
In this study, time-domain fluorescence diffuse optical tomography in biological tissue is numerically investigated using a total light approach. Total light is a summation of excitation light and zero-lifetime emission light divided by quantum yield. The zero-lifetime emission light is an emitted fluorescence light calculated by assuming that the fluorescence ...
Korbas Malgorzata - - 2008
Using synchrotron x-ray fluorescence mapping, we have examined the uptake and localization of organic mercury in zebrafish larvae. Strikingly, the greatest accumulation of methyl and ethyl mercury compounds was highly localized in the rapidly dividing lens epithelium, with lower levels going to brain, optic nerve, and various other organs. The ...
Kappaun Stefan - - 2008
Even though organic light-emitting device (OLED) technology has evolved to a point where it is now an important competitor to liquid crystal displays (LCDs), further scientific efforts devoted to the design, engineering and fabrication of OLEDs are required for complete commercialization of this technology. Along these lines, the present work ...
Lim Jong-Min - - 2008
We have demonstrated fluorescent liquid-core/air-cladding (LA) waveguides suitable for use as integrated optofluidic light sources. These waveguides were fabricated by conventional soft lithography using poly(dimethylsiloxane) (PDMS). Two-phase stratified flows of air and ethylene glycol with fluorescent dye were generated along the PDMS channel. Compared to the liquid-core/liquid-cladding (L(2)) waveguide, the ...
Heber Ulrich - - 2008
In order to survive sunlight in the absence of water, desiccation-tolerant green plants need to be protected against photooxidation. During drying of the chlorolichen Cladonia rangiformis and the cyanolichen Peltigera neckeri, chlorophyll fluorescence decreased and stable light-dependent charge separation in reaction centers of the photosynthetic apparatus was lost. The presence ...
Yuan Ye - - 2008
Dermis is the major source of the fluorescence and light scattering of skin. Tumor-induced degradation of the dermis is expected to change the fluorescence and light scattering properties of skin. To investigate how these fluorescence and light scattering properties are changed, human skin dermis was degraded with enzymes to mimic ...
Chignell Colin F - - 2008
Recently an article about the new energy-saving compact fluorescent light (CFL) bulbs appeared in Parade magazine [Rosenfeld, I. (2008) Parade Feb 3, 22]. Under the heading "Bright Lights, Bad Headache?" the writer states that "new research suggests some dangers" involving these lights because they are fluorescent and "can aggravate skin ...
Grass F - - 2008
In our measurements plasma and, especially, the main plasma protein, albumin, exhibits a long-lasting light-induced luminescence, which should be capable of transporting light along the blood circulation. Moreover, albumin shows intense fluorescence, with emission at 337 nm, which is controlled by bilirubin. Furthermore, it is known that tryptophan decarboxylase, the ...
Hänscheid Thomas - - 2008
In many resource-poor countries, diagnosis of tuberculosis is based on microscopy of Ziehl-Neelsen-stained smears. However, the fluorescent stain auramine performs better and allows the detection of more positive smears. The limitation for its widespread use has been the high cost for fluorescent microscopes, especially the frequent replacement of the expensive ...
Eisenstadt Doron - - 2008
Diatoms are an important group of primary producers in the aquatic environment. They are able to acclimate to fast changes in the light intensity by various mechanisms including a rise in non-photochemical fluorescence quenching (NPQ). The latter has been attributed to the xanthophyll cycle (XC) following activation of diadinoxanthin de-epoxidase ...
Xu Jing - - 2008
A light-emitting diode-induced fluorescence detector (LED-FD) for capillary electrophoresis was constructed and evaluated. A lamp LED with an enhanced emission spectrum and a band pass filter was used as the excitation light source. Refractive index matching fluid (RIMF) was used in the detection cell to reduce scattering light and the ...
Pais Andrea - - 2008
We report a high-sensitivity, disposable lab-on-a-chip with a thin-film organic light-emitting diode (OLED) excitation source and an organic photodiode (OPD) detector for on-chip fluorescence analysis. A NPB/Alq3 thin-film green OLED with an active area of 0.1 cm(2) was used as the excitation source, while a CuPC/C(60) thin-film OPD with 0.6 ...
Aslan Kadir - - 2008
In this letter we report the observation of angular-dependent Metal Enhanced Fluorescence (MEF) from fluorophores deposited onto silver island films (SiFs). When illuminated with laser light (473 nm) at angles of 45 and 90 degrees from the surface, SiFs scattered light at wide observation angles biased by the direction of ...
Traven Valery F - - 2008
Novel photochromic 5-(3'-coumarinyl)-4-(3''-thienyl)thiazoles have been synthesized. These compounds display intensive fluorescence emission in the open form A, which is modulated by light. Fluorescence intensity decreases significantly upon irradiation of A with UV-light (lambda<400 nm) due to formation of the cyclic form B. Irradiation of B with visible light (lambda>470 nm) ...
Andersen Charlotte M - - 2008
Degradation of the potential photosensitizers, riboflavin, chlorophyll, and porphyrin, in Danbo cheese by monochromatic light of wavelength 366, 436, or 546 nm was studied. Three cheeses were investigated, two conventional (16% fat and 25% fat) and one "organic" (25% fat). The effect of illumination was measured by fluorescence spectroscopy and ...
Rosenbom Annette E - - 2008
The study of mechanisms controlling preferential flow and transport in variably saturated fractured clayey till is often hindered by insufficient spatial resolution or unknown measuring volume. With the objective to study these mechanisms while circumventing the obstacles, tracer experiments with two fluorescent tracers Acid Yellow 7 (AY7) and Sulforhodamine B ...
Vredenberg Wim J - - 2008
The fluorescence induction F(t) of dark-adapted chloroplasts has been studied in multi-turnover 1 s light flashes (MTFs). A theoretical expression for the initial fluorescence rise is derived from a set of rate equations that describes the sequence of transfer steps associated with the reduction of the primary quinone acceptor Q ...
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