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Sagmeister Martin - - 2013
The use of organic photodiodes (OPDs) for measuring phosphorescent lifetimes of optochemical oxygen sensors is described. Phosphorescent indicators with lifetimes ranging from ∼5 to 60 μs have been studied using light-emitting diodes as the excitation source and organic photodiodes integrated into the sensor substrate for detection. A measurement system using an ...
van Amerongen Herbert - - 2013
Water oxidation in photosynthesis takes place in photosystem II (PSII). This photosystem is built around a reaction center (RC) where sunlight-induced charge separation occurs. This RC consists of various polypeptides that bind only a few chromophores or pigments, next to several other cofactors. It can handle far more photons than ...
Tseng Yao-Hsuan - - 2013
BACKGROUND: Traditional antibacterial photocatalysts are primarily induced by ultraviolet light to elicit antibacterial reactive oxygen species. New generation visible-light responsive photocatalysts were discovered, offering greater opportunity to use photocatalysts as disinfectants in our living environment. Recently, we found that visible-light responsive platinum-containing titania (TiO2-Pt) exerted high performance antibacterial property against ...
Maes Ludovic - - 2013
Quadrupedal locomotion is the result of complex interactions between biomechanical and neural systems. During steady gaits both systems are in stable states. When the animal changes its speed, transitions between gaits can occur where the different coordination parameters are dissociated. Consequently, transitions are the periods where it is possible to ...
Liu Rui - - 2013
Key issues in using organic light emitting diodes (OLEDs) as excitation sources in structurally integrated photoluminescence (PL)-based sensors are the low forward light outcoupling, the OLEDs' broad electroluminescence (EL) bands, and the long-lived remnant EL that follows an EL pulse. The outcoupling issue limits the detection sensitivity (S) as only ...
Zhao Jian - - 2013
The direct hydroamination of alkynes driven by visible light can be achieved in high yield and selectivity at ambient temperature using supported gold nanoparticles (AuNPs) as photocatalysts. Aniline molecules interact with visible light activated AuNPs meanwhile alkynes could be activated at active sites on the support. The findings reveal a ...
Arca Francesco - - 2013
Organic semiconductors are attractive for optical sensing applications due to the effortless processing on large active area of several cm(2), which is difficult to achieve with solid-state devices. However, compared to silicon photodiodes, sensitivity and dynamic behavior remain a major challenge with organic sensors. Here, we show that charge trapping ...
Xi Yumeng - - 2013
In the past five years, visible-light mediated photoredox catalysis has been emerging as one of the fastest growing fields in organic chemistry because of its low cost, easy availability and environmental benignness. This review intends to summarize recent research progress in novel methodology development and application in organic synthesis, and ...
Nagai Atsushi - - 2013
π in the sky: A squaraine-linked, conjugated two-dimensional porphyrin covalent organic framework (COF; see scheme; C: gray, H: white, N: blue, Cu: red) was synthesized. Owing to the π-conjugated linkage together with the eclipsed stacking of the units, this COF exhibits enhanced chemical and thermal stabilities. It absorbs a broad ...
Jurk Marcel - - 2013
Higher organisms as well as bacteria rely on information on the surrounding environment. In Bacillus subtilis, diverse extra-cellular stimuli are transformed into an intra-cellular response via a signal integration hub, called the stressosome. The subsequent signal transduction cascade initiates the general stress response (GSR). One of these stimuli is blue ...
Szalárdy O - - 2013
We tested whether incoming sounds are processed differently depending on how the preceding sound sequence has been interpreted by the brain. Sequences of a regularly repeating three-tone pattern, the perceived organization of which spontaneously switched back and forth between two alternative interpretations, were delivered to listeners. Occasionally, a regular tone ...
Choi C H - - 2013
The use of vibration is proposed as a means of controlling the settlement of marine fouling organisms. In this study, panels with embedded lead zirconate titanate, known as PZT, were placed in the field over 3 months. The panels were vibrated at different velocity levels at frequencies between 70 and 445 Hz. ...
McGraw Gregory J - - 2013
Multicolor electrophosphorescent organic light-emitting diode (OLED) pixel patterning by organic vapor jet printing (OVJP) is demonstrated, showing that this technique is capable of rapidly generating high-definition full-color displays. The resolution limits, and means to achieve them are described using a combination of simulation and experimental approaches.
Spiwoks-Becker Isabella - - 2013
Ribbon synapses are tonically active high-throughput synapses. The performance of the ribbon synapse is accomplished by a specialization of the cytomatrix at the active zone referred to as the synaptic ribbon (SR). Progress in our understanding of the structure-function relationship at the ribbon synapse has come from observations that, in ...
Roseboom Warrick - - 2013
A critical function of the human brain is to determine the relationship between sensory signals. In the case of signals originating from different sensory modalities, such as audition and vision, several processes have been proposed that may facilitate perception of correspondence between two signals despite any temporal discrepancies in physical ...
Liu Kong - - 2013
Silicon nanowire (SiNW) arrays show an excellent light-trapping characteristic and high mobility for carriers. Surface plasmon resonance of silver nanoparticles (AgNPs) can be used to increase light scattering and absorption in solar cells. We fabricated a new kind of SiNW/organic hybrid solar cell by introducing AgNPs. Reflection spectra confirm the ...
Zhang Lei - - 2013
Existing organic imaging circuits, which offer attractive benefits of light weight, low cost and flexibility, are exclusively based on phototransistor or photodiode arrays. One shortcoming of these photo-sensors is that the light signal should keep invariant throughout the whole pixel-addressing and reading process. As a feasible solution, we synthesized a ...
Sawayama Masataka - - 2013
The articulation effect refers to a change in lightness contrast induced by adding small patches of different luminances to a uniform background surrounding a target in a lightness contrast display. This study investigated how local luminance signals are integrated to generate the articulation effect. We asked whether spatial organization due ...
Dhahri Samia - - 2013
We present a study about AFM imaging of living, moving or self-immobilized bacteria in their genuine physiological liquid medium. No external immobilization protocol, neither chemical nor mechanical, was needed. For the first time, the native gliding movements of Gram-negative Nostoc cyanobacteria upon the surface, at speeds up to 900 µm/h, ...
Zayat Leonardo - - 2013
Octahedral Ru(II) polypyridyl complexes constitute a superb platform to devise photoactive triggers capable of delivering entire molecules in a reliable, fast, efficient and clean way. Ruthenium coordination chemistry opens the way to caging a wide range of molecules, such as amino acids, nucleotides, neurotransmitters, fluorescent probes and genetic inducers. Contrary ...
Naramura Tomotaka - - 2013
Bacteria tests are conducted for quality control in many different industries. However, the cultivation method takes a long period of time to obtain results and there are more than a few bacteria that are difficult to cultivate. We have focused on the autofluorescence substance in the bacteria to detect them, ...
Reznick Yana - - 2013
Recently there were several publications on the bactericidal effect of visible light, most of them claiming that blue part of the spectrum (400 nm-500 nm) is responsible for killing various pathogens(1-5). The phototoxic effect of blue light was suggested to be a result of light-induced reactive oxygen species (ROS) formation ...
Parija Subhash Chandra - - 2013
The unicellular protist Blastocystis has long been an unsolved puzzle for taxonomists, microbiologists and clinicians. Over the years, the organism has been bounced on and off the different branches of the tree of life due the possession of unique phenotypic characters intermediary to different organisms. The organism is polymorphic with ...
Reigh Shang Yik - - 2013
Peritrichous bacteria exploit bundles of helical flagella for propulsion and chemotaxis. Here, changes in the swimming direction (tumbling) are induced by a change of the rotational frequency of some flagella. Employing coarse-grained modeling and simulations, we investigate the dynamical properties of helical flagella bundles driven by mismatched motor torques. Over ...
Verma Subhash C - - 2013
Quorum sensing is an intercellular form of communication that bacteria use to coordinate group behaviors such as biofilm formation and the production of antibiotics and virulence factors. The term quorum sensing was originally coined to describe the mechanism underlying the onset of luminescence production in cultures of the marine bacterium ...
Kwak Kiyeol - - 2013
We report luminescent characteristics and mechanical stability of a flexible organic light-emitting diode (FOLED) using an amorphous ZnO-doped In2O3 (a-IZO) anode with a low sheet resistance of and a high optical transparency of 86%. The FOLED consisting of a-IZO/poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS)/poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4, 8-diyl)] (F8BT)/LiF/Al exhibits the efficient luminescent characteristics, which are ...
Fuller Kevin K - - 2013
Light is a pervasive environmental factor that regulates development, stress resistance, and even virulence in numerous fungal species. Though much research has focused on signaling pathways in Aspergillus fumigatus, an understanding of how this pathogen responds to light is lacking. In this report, we demonstrate that the fungus does indeed ...
Arredondo Belén - - 2013
A visible light communication (VLC) system using an organic bulk heterojunction photodetector (OPD) is presented. The system has been successfully proven indoors with an audio signal. The emitter consists of three commercial high-power white LEDs connected in parallel. The receiver is based on an organic photodetector having as active layer ...
Rabani Amit A Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, - - 2013
A large variety of motile bacterial species exhibit collective motions while inhabiting liquids or colonizing surfaces. These collective motions are often characterized by coherent dynamic clusters, where hundreds of cells move in correlated whirls and jets. Previously, all species that were known to form such motion had a rod-shaped structure, ...
Norsworthy Allison N AN Department of Microbiology and Immunology, Loyola University Medical Center Maywood, IL, - - 2013
Bacteria successfully colonize distinct niches because they can sense and appropriately respond to a variety of environmental signals. Of particular interest is how a bacterium negotiates the multiple, complex environments posed during successful infection of an animal host. One tractable model system to study how a bacterium manages a host's ...
Campanella Sara - - 2013
The 'provisional hypothesis' of pangenesis seems to be associated with a reduction of the role of geographical isolation as a factor of speciation or novelty in Darwinian thinking. On the one hand, this fact draws the attention on the interacting processes concerning the internal dynamics of organisms' development together with ...
Heath-Heckman Elizabeth A C EA Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, - - 2013
The symbiosis between the squid Euprymna scolopes and its luminous symbiont, Vibrio fischeri, is characterized by daily transcriptional rhythms in both partners and daily fluctuations in symbiont luminescence. In this study, we sought to determine whether symbionts affect host transcriptional rhythms. We identified two transcripts in host tissues (E. scolopes ...
Grovenstein Phillip B PB Department of Biology, University of West Georgia, Carrollton GA, 30118, - - 2013
The green micro-alga Chlamydomonas reinhardtii is an elegant model organism to study oxygenic photosynthesis. Chlorophyll (Chl) and heme are major tetrapyrroles that play an essential role in photosynthesis and respiration. These tetrapyrroles are synthesized via a common branched pathway that involves mainly enzymes, encoded by nuclear genes. One of the ...
Ruiz-González Clara C Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSIC Barcelona, Spain ; Département des Sciences Biologiques, Université du Québéc à Montréal Montréal, QC, - - 2013
Heterotrophic bacterioplankton are main consumers of dissolved organic matter (OM) in aquatic ecosystems, including the sunlit upper layers of the ocean and freshwater bodies. Their well-known sensitivity to ultraviolet radiation (UVR), together with some recently discovered mechanisms bacteria have evolved to benefit from photosynthetically available radiation (PAR), suggest that natural ...
Sun Henry J HJ Division of Earth and Ecosystem Sciences, Desert Research Institute, Las Vegas, NV 89119, USA. - - 2013
Cyanobacteria and lichens living under sandstone surfaces in the McMurdo Dry Valleys require snow for moisture. Snow accumulated beyond a thin layer, however, is counterproductive, interfering with rock insolation, snow melting, and photosynthetic access to light. With this in mind, the facts that rock slope and direction control colonization, and ...
Noever Simon J - - 2012
Thickness resolved measurements of ambipolar thin-film transistor characteristics track the charging of an organic-organic heterojunction. Combined with structural investigation methods such as AFM and GIXS, this leads to a better understanding of the physics in state of the art devices such as organic solar cells, organic light emitting diodes and ...
Kotecha Abhay - - 2012
Purple bacteria have peripheral light-harvesting (PLH) complexes adapted to high-light (LH2) and low-light (LH3, LH4) growth conditions. The latter two have only been fully characterised in Rhodopseudomonas acidophila 7050 and Rhodopseudomonas palustris CGA009, respectively. It is known that LH4 complexes are expressed under the control of two light sensing bacteriophytochromes ...
Liberton Michelle M Department of Biology, Washington University, St. Louis, Missouri 63130, - - 2013
Cyanobacteria are prokaryotes that can use photosynthesis to convert sunlight into cellular fuel. Knowledge of the organization of the membrane systems in cyanobacteria is critical to understanding the metabolic processes in these organisms. We examined the wild-type strain of Synechocystis sp. PCC 6803 and a series of mutants with altered ...
Lee Chil Won - - 2012
A twist in the tail: The effect of varying the substitution position of dibenzofuran on its photophysical properties and organic light-emitting diode device performance was systematically investigated by synthesizing three compounds with 2-, 3- and 4-substitution patterns. The proper selection of substitution position can control the photophysical properties and performance ...
Almeida Fernando P - - 2012
Magnetotactic bacteria move by rotating their flagella and concomitantly are aligned to magnetic fields because they present magnetosomes, which are intracellular organelles composed by membrane-bound magnetic crystals. This results in magnetotaxis, which is swimming along magnetic field lines. Magnetotactic bacteria are morphologically diverse, including cocci, rods, spirilla and multicellular forms ...
Kim You-Hyun - - 2012
High contrast blue organic light-emitting diodes were fabricated using an inorganic multilayer of NPB (700 Å)/MADN (200 Å)/Alq<sub>3</sub> (300 Å)/LiF (10 Å)/Al (70 Å)/ZnSe (300 Å)/Al (1000 Å). The optical and electrical characteristics were measured and compared to conventional organic light-emitting devices (OLEDs) and OLEDs with polarizers. OLEDs with the metal multilayer cathodes had an improved contrast ...
Sokolov Andrey - - 2012
A suspension of microswimmers, the simplest realization of active matter, exhibits novel material properties: the emergence of collective motion, reduction in viscosity, increase in diffusivity, and extraction of useful energy. Bacterial dynamics in dilute suspensions suggest that hydrodynamic interactions and collisions between the swimmers lead to collective motion at higher ...
Petrun Branden - - 2013
Vibrio fischeri are bioluminescent marine bacteria that can be isolated from their symbiotic animal partners or from ocean water. A V. fischeri population increases exponentially inside the light organ of the Hawaiian bobtail squid (Euprymna scolopes) while the host is quiescent during the day. This bacterial light organ population reaches ...
Chang Chia Min - - 2012
Using the curved arrangement of Au nanobumps, the scattering of surface plasmon waves are transformed into spots at desired locations and altitudes in three-dimensional space. The light can be modulated into desired light patterns. This work is very promising for compact plasmonic circuitry, projection, live-cell imaging, optical sensing, and holography.
Suetsugu Noriyuki - - 2012
Many organisms, including bacteria, fungi, animal, plants and algae, utilize blue light to adapt to a fluctuating light environment. Plants and algae such as photosynthetic stramenopiles in particular require light energy for photosynthesis and have thus evolved a range of sophisticated light-sensing systems to efficiently utilize light information for growth, ...
Thor Maria - - 2012
Background and purpose. Internal organ motion over a course of radiotherapy (RT) leads to uncertainties in the actual delivered dose distributions. In studies predicting RT morbidity, the single estimate of the delivered dose provided by the treatment planning computed tomography (pCT) is typically assumed to be representative of the dose ...
Nishio Koichi - - 2012
Biological energy-conversion systems are attractive in terms of their self-organizing and self-sustaining properties and are expected to be applied towards environmentally friendly bioenergy processes. Recent studies have demonstrated that sustainable light/electricity-conversion systems, termed microbial solar cells (MSCs), can be constructed using naturally occurring microbial communities. To better understand the energy-conversion ...
Di Salvo Mario E - - 2012
A surprising feature of many bacterial motors is the apparently conserved form of their torque-frequency relation. Experiments indicate that the torque provided by the bacterial rotary motor is approximately constant over a large range of angular speeds. This is observed in both monotrichous and peritrichous bacteria, independently of whether they ...
Miyashita Shuhei - - 2012
Abstract Self-organization is a phenomenon found in biomolecular self-assembly by which proteins are spontaneously driven to assemble and attain various functionalities. This study reports on self-organized behavior in which distributed centimeter-sized modules stochastically aggregate and exhibit a translational wheeling motion. The system consists of two types of centimeter-sized water-floating modules: ...
Cangiano Lorenzo - - 2012
Rod photoreceptors detect single photons through a tradeoff of light collecting ability, amplification and speed. Key roles are played by rhodopsin (Rh) and transducin (G(t)), whose complex supramolecular organization in outer segment disks begs for a functional interpretation. Here we review past and recent evidence of a temperature-dependence of photon ...
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