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Rockwell Nathan Clarke - - 2012
Phytochromes are red/far-red photosensory proteins that regulate adaptive responses to light via photoswitching of cysteine-linked linear tetrapyrrole (bilin) chromophores. The related cyanobacteriochromes (CBCRs) extend the photosensory range of the phytochrome superfamily to shorter wavelengths of visible light. CBCRs and phytochromes share a conserved Cys residue required for bilin attachment. In ...
Martiniani Stefano - - 2012
The order of regeneration for DSCs based on two organic dyes has been investigated by transient absorption spectroscopy on devices under operating conditions and determined to be 2nd order in iodide. The results shed light on the mechanism and limits to the regeneration rate relative to oxidation potential.
Liu Feng - - 2012
We show that, under the right conditions, one can make highly accurate polarization-based measurements without knowing the absolute polarization state of the probing light field. It is shown that light, passed through a randomly varying birefringent material has a well-defined orbit on the Poincar sphere, which we term a generalized ...
Kalashnikov Maxim - - 2012
We report a method of assessing the contribution of whole cell body and its nucleus to the clinically most relevant backward light scattering. We first construct an experimental system that can measure forward scattering and use the system to precisely extract the optical properties of a specimen such as the ...
Lee Chao-Te - - 2012
The proposed patterned polarizer rather than the conventional ±λ/4 polarizer can further reduce the crosstalk through its corresponding glass for stereoscopic LCDs and can be fabricated by using the same patterned alignment technique. The patterned polarizer comprises a linear polarizer, a patterned retarder and a biaxial film. The maximum crosstalk ...
Moreno Ignacio - - 2012
We present a method to generate complete arbitrary spatially variant polarization modulation of a light beam by means of a parallel aligned nematic liquid crystal spatial light modulator (SLM). We first analyze the polarization modulation properties in a transmission mode. We encode diffraction gratings onto the SLM and show how ...
Keller James M - - 2012
The mammalian cochlea receives and analyzes sound at specific places along the cochlea coil, commonly referred to as the tonotopic map. Although much is known about the cell-level molecular defects responsible for severe hearing loss, the genetics responsible for less severe and frequency-specific hearing loss remains unclear. We recently identified ...
Cole Benjamin J - - 2012
Time-resolved hypocotyl length measurements in seedlings have the potential to greatly aid genetic studies looking at light, hormone, and circadian regulation of cell expansion. Recently, several computer-based tools have been developed to quantify hypocotyl length during photomorphogenesis and early seedling development. Here we detail a method for quantifying Arabidopsis seedling ...
Santos Ana M - - 2012
Both proNGF and the neurotrophin receptor p75 (p75(NTR)) are known to regulate photoreceptor cell death caused by exposure of albino mice to intense illumination. ProNGF-induced apoptosis requires the participation of sortilin as a necessary p75(NTR) co-receptor, suggesting that sortilin may participate in the photoreceptor degeneration triggered by intense lighting. We ...
Grellet-Tinner Gerald - - 2012
The Cretaceous vertebrate assemblages of Romania are famous for geographically endemic dwarfed dinosaur taxa. We report the first complete egg clutches of a dwarf lithostrotian titanosaur, from Toteşti, Romania, and its reproductive adaptation to the "island effect". The egg clutches were discovered in sequential sedimentary layers of the Maastrichtian Sânpetru ...
Vieira Jacqueline - - 2012
Cryptochromes are conserved flavoprotein receptors found throughout the biological kingdom with diversified roles in plant development and entrainment of the circadian clock in animals. Light perception is proposed to occur through flavin radical formation that correlates with biological activity in vivo in both plants and Drosophila. By contrast, mammalian (Type ...
Steck Kathrin - - 2012
How can odor-guided behavior of numerous individual Drosophila be assessed automatically with high temporal resolution? For this purpose we introduce the automatic integrated tracking and odor-delivery system Flywalk. In fifteen aligned small wind tunnels individual flies are exposed to repeated odor pulses, well defined in concentration and timing. The flies' ...
Bailes Helena J HJ Faculty of Life Sciences, The University of Manchester, Manchester, United - - 2012
Originally developed to regulate neuronal excitability, optogenetics is increasingly also used to control other cellular processes with unprecedented spatiotemporal resolution. Optogenetic modulation of all major G-protein signalling pathways (Gq, Gi and Gs) has been achieved using variants of mammalian rod opsin. We show here that the light response driven by ...
Schmitz Frank - - 2012
Photoreceptors, the light-sensitive receptor neurons of the retina, receive and transmit a plethora of visual informations from the surrounding world. Photoreceptors capture light and convert this energy into electrical signals that are conveyed to the inner retina. For synaptic communication with the inner retina, photoreceptors make large active zones that ...
Conte Vito - - 2012
The article provides a biomechanical analysis of ventral furrow formation in the Drosophila melanogaster embryo. Ventral furrow formation is the first large-scale morphogenetic movement in the fly embryo. It involves deformation of a uniform cellular monolayer formed following cellularisation, and has therefore long been used as a simple system in ...
López-del Hoyo Natalia - - 2012
Guanylate cyclase activating proteins are EF-hand containing proteins that confer calcium sensitivity to retinal guanylate cyclase at the outer segment discs of photoreceptor cells. By making the rate of cGMP synthesis dependent on the free intracellular calcium levels set by illumination, GCAPs play a fundamental role in the recovery of ...
Ratushny Alexander V - - 2012
Positive feedback is a common mechanism enabling biological systems to respond to stimuli in a switch-like manner. Such systems are often characterized by the requisite formation of a heterodimer where only one of the pair is subject to feedback. This ASymmetric Self-UpREgulation (ASSURE) motif is central to many biological systems, ...
Gonzalo-Gomez Alicia - - 2012
HCN channels are becoming pharmacological targets mainly in cardiac diseases. But apart from their well-known role in heart pacemaking, these channels are widely expressed in the nervous system where they contribute to the neuron firing pattern. Consequently, abolishing Ih current might have detrimental consequences in a big repertoire of behavioral ...
Plachetzki David C - - 2012
Cnidocytes, the eponymous cell type of the Cnidaria, facilitate both sensory and secretory functions and are among the most complex animal cell types known. In addition to their structural complexity, cnidocytes display complex sensory attributes, integrating both chemical and mechanical cues from the environment into their discharge behavior. Despite more ...
Vang Lar L - - 2012
The behavioral responses of adult Drosophila fruit flies to a variety of sensory stimuli--light, volatile and non-volatile chemicals, temperature, humidity, gravity, and sound--have been measured by others previously. Some of those assays are rather complex; a review of them is presented in the Discussion. Our objective here has been to ...
Yoshii Taishi - - 2012
Circadian clocks play an essential role in adapting the activity rhythms of animals to the day-night cycles on earth throughout the four seasons. In many animals, including the fruit fly Drosophila melanogaster, two separate but mutually coupled clocks in the brain -morning (M) and evening (E) oscillators- control the activity ...
Sudo Yuki - - 2012
Light is one of the most important energy sources and signals providing critical information to biological systems. The photoreceptor rhodopsin, which possesses retinal chromophore (vitamin A aldehyde) surrounded by seven transmembrane alpha-helices, is widely dispersed in prokaryotes and in eukaryotes. Although rhodopsin molecules work as distinctly different photoreceptors, they can ...
Hwang Yongyun - - 2012
Transmission of mechanical stimuli through the actin cytoskeleton has been proposed as a mechanism for rapid long-distance mechanotransduction in cells; however, a quantitative understanding of the dynamics of this transmission and the physical factors governing it remains lacking. Two key features of the actin cytoskeleton are its viscoelastic nature and ...
Shiba Kohei - - 2012
In this study, we describe a novel application for light scattering, a method widely used for separation of molecules in solution based on their size. We demonstrate that light scattering analysis can monitor the change in particle size of protein 4.1R prior to and after binding to red blood cell ...
Hazlerigg David - - 2012
The capacity to measure day length (photoperiod) is a trait subject to intense evolutionary pressure, and the circadian system has become an important part of the photoperiodic machinery. With the exception of mammals, vertebrates possess multiple sites of photosensitivity within the central nervous system through which light responses may be ...
Salmela Iikka - - 2012
The importance of voltage-dependent conductances in sensory information processing is well-established in insect photoreceptors. Here we present the characterization of electrical properties in photoreceptors of the cockroach (Periplaneta americana), a nocturnal insect with a visual system adapted for dim light. Whole-cell patch-clamped photoreceptors had high capacitances and input resistances, indicating ...
von Wettberg Eric J B - - 2012
Correlations between developmentally plastic traits may constrain the joint evolution of traits. In plants, both seedling de-etiolation and shade avoidance elongation responses to crowding and foliage shade are mediated by partially overlapping developmental pathways, suggesting the possibility of pleiotropic constraints. To test for such constraints, we exposed inbred lines of ...
Deng Yunyan - - 2012
Light has significant effect on the growth and development of Saccharina japonica, but there are limited reports on blue light mediated physiological responses and molecular mechanism. In this study, high-throughput paired-end RNA-sequencing (RNA-Seq) technology was applied to transcriptomes of S. japonica exposed to blue light and darkness, respectively. Comparative analysis ...
Hughes Steven - - 2012
Melanopsin expressing retinal ganglion cells represent a third class of ocular photoreceptors and are involved in irradiance detection and non-image-forming responses to light including pupil constriction, circadian entrainment, and regulation of sleep. Over recent years, there has been a rapid increase in our understanding of the anatomical variety of pRGC ...
Sun Xiaodong - - 2012
The stomatal pores are located on the plant leaf epidermis and regulate CO(2) uptake for photosynthesis and the loss of water by transpiration. Their stomatal aperture therefore affects photosynthesis, water use efficiency, and agricultural crop yields. Blue light, one of the environmental signals that regulates the plant stomatal aperture, is ...
Sanger Thomas J - - 2012
Complex organismal structures are organized into modules, suites of traits that develop, function, and vary in a coordinated fashion. By limiting or directing covariation among component traits, modules are expected to represent evolutionary building blocks and to play an important role in morphological diversification. But how stable are patterns of ...
Morin L P LP Department of Psychiatry, Stony Brook University Medical Center, Stony Brook, NY, USA. - - 2011
Four studies were performed to further clarify the contribution of rod/cone and intrinsically photoreceptive retinal ganglion cells to measures of entrainment, dark preference, light-induced locomotor suppression and photosomnolence. Wild type (WT), retinally degenerate (rd/rd), and melanopsin-less (OPN4⁻/⁻) mouse strains were compared. In Experiment 1, mice were exposed to a graded ...
Edelmann Geoffrey F - - 2011
Compressive sensing (CS) is compared with conventional beamforming using horizontal beamforming of at-sea, towed-array data. They are compared qualitatively using bearing time records and quantitatively using signal-to-interference ratio. Qualitatively, CS exhibits lower levels of background interference than conventional beamforming. Furthermore, bearing time records show increasing, but tolerable, levels of background ...
Huang Shih-Hao - - 2011
This paper describes a light-addressable electrolytic system used to perform an electrodeposition of calcium alginate hydrogels using a digital micromirror device (DMD). In this system, a patterned light illumination is projected onto a photoconductive substrate serving as a photo-anode to electrolytically produce protons, which can lead to a decreased pH ...
Pendergast Julie S JS Department of Biological Sciences, Vanderbilt University , Nashville, Tennessee 37235, - - 2011
Masking is an acute effect of an external signal on an overt rhythm and is distinct from the process of entrainment. In the current study, we investigated the phase dependence and molecular mechanisms regulating masking effects of light pulses on spontaneous locomotor activity in mice. The circadian genes, Period1 (Per1) ...
Gholizadeh H - - 2011
BACKGROUND: The method of attachment of prosthesis to the residual limb (suspension) and socket fitting is a critical issue in the process of providing an amputee with prosthesis. Different suspension methods try to minimize the pistoning movement inside the socket. The Seal-In(®) X5 and Dermo(®) Liner by Ossur are new ...
Hogg Christopher - - 2011
The Arctic has extreme seasonal changes in light levels and is proportionally UV-rich because of scattering of the shorter wavelengths and their reflection from snow and ice. Here we show that the cornea and lens in Arctic reindeer do not block all UV and that the retina responds electrophysiologically to ...
Goo Yong Sook - - 2011
Retinal prostheses are being developed to restore vision for those with retinal diseases such as retinitis pigmentosa or age-related macular degeneration. Since neural prostheses depend upon electrical stimulation to control neural activity, optimal stimulation parameters for successful encoding of visual information are one of the most important requirements to enable ...
Kočí Jan - - 2011
Synthesis and chemiluminescent properties of a new 1,2-dioxetane chemiluminophore bearing a 7-hydroxycoumarin moiety are presented. The 1,2-dioxetane decomposition ended up with strong and long-lived emission of light. This new structure opens way to the development of a new generation of bright chemiluminescent bio-probes.
Corrochano Luis M - - 2011
Fungi respond and adapt to many environmental signals including light. The photobiology of fungi has been extensively investigated, but in recent years the identification of the first fungal photoreceptor, WC-1 in the ascomycete Neurospora crassa, and the discovery that similar photoreceptors are required for photoreception in other ascomycete, basidiomycete and ...
Barry Jeremy - - 2011
To ask if the properties of spatial learning supported by the hippocampus are distinct from the properties of conditioning, we conducted a blocking-like experiment in which the measured variable was not a conditioned response but rather the ability of a novel visual stimulus to control the location of place cell ...
Parker Karen J KJ Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, USA. - - 2011
The startle response, a simple defensive response to a sudden stimulus signaling proximal threat, has been well studied in rodents and humans, but has been rarely examined in monkeys. The first goal of the present studies was to develop a minimally immobilizing startle measurement paradigm and validate its usefulness by ...
Kojima Daisuke - - 2011
A variety of animal species utilize the ultraviolet (UV) component of sunlight as their environmental cues, whereas physiological roles of UV photoreception in mammals, especially in human beings, remain open questions. Here we report that mouse neuropsin (OPN5) encoded by the Opn5 gene exhibited an absorption maximum (λmax) at 380 ...
Li Jigang - - 2011
Phytochromes are red (R)/far-red (FR) light photoreceptors that play fundamental roles in photoperception of the light environment and the subsequent adaptation of plant growth and development. There are five distinct phytochromes in Arabidopsis thaliana, designated phytochrome A (phyA) to phyE. phyA is light-labile and is the primary photoreceptor responsible for ...
Carle Corinne F - - 2011
The recent development of an objective and noninvasive perimetric technique using pupillary responses to sparse multifocal visual stimuli shows promise for the assessment of visual function in glaucoma. This study assesses the sensitivity and specificity of four variants of dichoptic multifocal pupillographic objective perimetry (mfPOP) with a high-resolution, 40-region/field stimulus. ...
Olsen Kirk N - - 2010
Three experiments investigate psychological, methodological, and domain-specific characteristics of loudness change in response to sounds that continuously increase in intensity (up-ramps), relative to sounds that decrease (down-ramps). Timbre (vowel, violin), layer (monotone, chord), and duration (1.8 s, 3.6 s) were manipulated in Experiment 1. Participants judged global loudness change between ...
Guest Duncan - - 2010
Nosofsky (1983) reported that additional stimulus presentations within a trial increase discriminability in absolute identification, suggesting that each presentation creates an independent stimulus representation, but it remains unclear whether exposure duration or the formation of independent representations improves discrimination in such conditions. Experiment 1 replicated Nosofsky's result. Experiments 2 (masking ...
McFarland Dennis J DJ Laboratory of Neural Injury and Repair, Wadsworth Center, New York State Dept. of Health, Albany, NY 12201-0509, USA. - - 2011
Brain-computer interface technology can restore communication and control to people who are severely paralyzed. We have developed a non-invasive BCI based on the P300 event-related potential that uses an 8×9 matrix of 72 items that flash in groups of 6. Stimulus presentation rate (i.e., flash rate) is one of several ...
Smith Kiersten S KS Department of Psychiatry, Harvard Medical School, Belmont, MA 02478, USA. - - 2011
The late preweanling rat has potential as a preclinical model for disorders initially manifested in early childhood that are characterized by dysfunctional interactions with specific stimuli (e.g., obsessive-compulsive disorder and autism). No reports, however, of specific-stimulus exploration in the late preweanling rat are found in the literature. We examined the ...
Bernasconi Fosco - - 2011
Both neural and behavioral responses to stimuli are influenced by the state of the brain immediately preceding their presentation, notably by pre-stimulus oscillatory activity. Using frequency analysis of high-density electroencephalogram coupled with source estimations, the present study investigated the role of pre-stimulus oscillatory activity in auditory spatial temporal order judgments ...
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